T.O. 21M-LGM25C-1

The "Dash One"
This is a manual for the United States Titan II Intercontinental Ballistic Missile weapon system as displayed at the Titan Missile Museum in Sahuarita, Arizona.

INTRODUCTION
The LGM-25C Weapon System consists of an inertially guided, liquid fueled, airborne weapon and associated ground equipment necessary to maintain and launch the airborne weapon. The weapon system is capable of destroying enemy targets over 5000 nautical miles distant. The launch complex is designed to maintain an operational readiness condition with no outside support after sustaining an attack that destroys all non-hardened facilities. For maximum safety and effectiveness, individual launch complexes are separated by distance of 7 to 10 nautical miles. All in-commission missiles are maintained in a constant alert condition and may be counted down individually or simultaneously. Safety rules for the LGM-25C (Titan II) MK6 RV/MK53 Weapon System (U) are contained in AFR 122-22. Squadron maintenance areas provide facilities for supply, administration, operations, and maintenance necessary to maintain the launch complexes in a constant state of readiness.

LAUNCH COMPLEX.
The launch complex includes both above ground and hardened underground facilities. Hardened facilities include the missile silo, control center, blast lock, interconnecting cable-ways, emergency escape hatch, and hardened communications equipment. Above ground, non-hardened facilities include vehicle parking areas, security fencing and lighting, propellant and electrical connections, static grounding system, commercial power lines, a transformer, cooling tower pits, access portal, non-hardened antennas, soft water storage, area security surveillance system, and weather instruments.

MISSILE SILO.
The missile silo (figure 1-2) is a reinforced, concrete structure with inside dimensions of approximately 146 feet in depth and 55 feet in diameter. A launch duct, constructed with a sound-attenuating lining, is located in the center of the silo. Associated installed equipment and structures include a silo closure door, retractable work platforms, hazard sensing devices, and a small equipment and personnel elevator operating between levels 2 and 8. Two exhaust ducts carry missile exhaust and ingested air from the flame deflector, through deflecting cascade vanes, to the surface. Equipment areas are located between the launch duct and the missile silo walls on nine separate levels. Equipment contained on the various levels is as follows:


 * Level 1. Hydraulic panel, power pump unit, accumulator rack, nitrogen tanks, elevator power control, silo closure door operating equipment, silo elevator operating machinery, and control station for retractable platforms on level 1.
 * Level 2, Water chiller units, main and spare chilled water circulating pumps, chilled water makeup tank, emergency eye wash and shower, cables and cable-way entrance, control station for retractable platforms on level 2, and two retractable platform hydraulic power valve panels, and an environmental protection unit.
 * Level 3. Air handler, air supply and exhaust fans, ducting, steam separator, diesel generator and heat exchanger, switch gear, main circuit breakers, motor control center, shower and eyewash, two blast valves (intake and exhaust), control station for retractable platforms on levels 3 and 4, manhole to hard storage tank, and retractable platform hydraulic power valve panel.
 * Level 4. Exhaust fan, air washer and water tank, two blast valves (air intake and exhaust), retractable platform hydraulic power valve panel, and silo blast valve control station.
 * Level 5. Launch duct air conditioning unit, diesel service tank, slop tank and pumps, chilled water pump, water tank, control station for retractable work platforms on level 5, and retractable platform hydraulic power valve panel.
 * Level 6. Air receiver, nitrogen tank, hydro-pneumatic power unit for silo blast valves and retractable work platforms, heating and ventilating control panel, water tank, valve panels, accumulators, pumps, reservoir, and fuel oxidizer vapor sensor racks.
 * Level 7. Starting air pressure vessels, air compressor, standby air compressor, utility air pressure vessels, main cooling water pump, spare cooling water pump, fire protection pump, cooling water mix pump, industrial water pump, emergency eyewash and shower, retractable platform hydraulic power valve panel, control station for retractable platforms on level 7, and domestic water pumps. The thrust mount and shock isolation system that supports the missile is located at this level (inside launch duct),
 * Levels 8 and 9. Engine deluge system, dehumidifier, oxidizer pump room, emergency eyewash and shower (two), sump pumps, flame deflector and sump, fuel pump room, sump spray, and sound attenuation system.

SILO CLOSURE DOOR.
The launch silo closure door consists of the closure door, wheel trucks, track rails, buffers and a door actuating system. The door actuating system consists of rail bridge jacks, door locks, a drive unit, cables, a pneudraulic power system, and electrical, hydraulic, and pneumatic controls. 1-9. The door is a 740-ton structure of steel and concrete mounted on four 4-wheeled truck assemblies. The purpose of the door Is to protect the silo from nearby nuclear blasts and resulting radiation. When closed, the door rests upon a seal with truck wheels clear of the rails. Door locks hold the door in the lowered, locked position, preventing movement from shock or vibration. For maintenance, the door may be opened or closed locally from the silo closure maintenance control panel located at silo level 1 after being activated by a key switch. The door is normally opened automatically during launch sequence by the control-monitor group in the control center. Door opening, by local control, is initiated by pressing and holding the silo closure maintenance control panel UNLOCK push-button until an unlocked indication is present. An override open panel mounted directly below and electrically connected to the maintenance control panel, contains electrical circuitry to automatically bypass faulty circuits of the maintenance control panel. An override close control panel is located beside the maintenance control panel and may be operated manually by a push-button mounted on the face of the panel in the event of an automatic close control failure. A door lock cylinder directional control valve solenoid is energized and directs hydraulic fluid at 3315 to 3525 psig from pressurized accumulators to the four lock cylinder unlock ports. The door locks rotate and lower to the fully unlocked and lowered position. Pressing and holding the silo closure maintenance control panel RAISE push-button energizes the rail bridge jacks directional control valve solenoid, directing hydraulic fluid to four rail bridge jack cylinders, raising the door wheel trucks even with the track rails. Pressing and holding the silo closure maintenance control panel OPEN push-button energizes the drive unit directional control valve solenoid, directing fluid to the drive unit motors. The drive unit motors turn two drum units with wrap cables attached to the closure door, opening the silo closure door. The door is arrested by hydraulic buffers, preventing damage to door and door arresters. Limit switches are installed at door activating locks, rail bridge jacks, and door arresting points, to monitor silo closure door opening and closing cycles from the silo closure maintenance control panel, control-monitor group (CMG), and launch control complex facilities console (LCCFC). The door is closed locally by the CLOSE, LOWER, and LOCK push-buttons on the silo closure maintenance control panel. The door is buffered by the door closing buffer. During launch sequence, the door is automatically controlled by the CMG and door limit switches. Upon demand, the door locks rotate and lower, the door raises, and the drive unit is energized. The force of the drive unit opens the closure door within 17 to 21 seconds, including unlocking and raising time. Debris on tracks may extend opening time. If silo closure door opening buffers or bumpers have been destroyed by a blast, an emergency means of stopping the door is required to prevent damage to the drive cables and hydraulic system by over-travel of the door. Emergency door stopping capability is provided by removal of both the 4-foot track rail sections and the adjacent 2-foot removable sections. Rail sections are stored on a concrete slab near the silo closure door tracks for ease of replacement when required. The silo closure door will operate normally with these rail sections removed and opening buffers and bumpers intact. If the silo closure overruns Limit switches, the silo closure (fully) open signal will be locked up in CMG-1 and launch sequence will continue.

To close the door, the sequence is reversed. The cable system drives the door to the full closed position and the hydraulic shock absorber in the door closing buffer slows it to a stop. Two sequencing controls lower the rail bridge jacks and set the door on a seal. The control then actuates the locking mechanisms, securing the door in place. Closing time is 17 to 21 seconds.

CONTROL CENTER.
The control center (figure 1-3) is a buried, reinforced, concrete structure designed to withstand the effects of a nuclear blast. The ground shock accompanying the blast is nullified in the control center by a three-level, steel, shock- isolation cage, which is supported by eight shock mounts hung from the domed roof. Grounding of the control center is accomplished by completely enclosing the structure with a 1/4-inch steel shell. The control center contains living quarters, communications equipment, battery power supplies, equipment for checkout and monitoring of the weapon system, and equipment for initiating launch sequence. These facilities allow the missile combat crew to maintain an alert condition with a minimum of down time. By the use of monitoring equipment contained in the control center, malfunctions which could affect launch capability can be recognized and isolated. Radio, telephone, and loudspeaker systems provide inter- and intra-site communications. VAFB equipment is not shown in figure 1-3.

BLAST LOCK, CABLE-WAYS, AND DECONTAMINATION AREA.
(See figure 1-4.) The blast lock is a buried, rectangular shaped, reinforced concrete structure with steel blast doors at all personnel openings. The blast lock is adjacent to the access portal and decontamination area. Cable-ways extend from the blast lock to the control center and from the decontamination area to the silo. The cable-ways are 9-1/2 feet in diameter, and are constructed with steel floors. Cable-ways provide for passage of personnel and equipment, control wiring, utility distribution, air ducts, and piping. Blast door No. 8 is installed where the cable-way from the control center connects with blast lock junction No. 201. Blast door No. 9 separates blast lock junction No. 201 and the decontamination area. The personnel decontamination area, located between blast door No. 9 and silo cable-way, contains a dressing room, decontamination shower, and an emergency reporting net telephone. The decontamination area is used for showering prior to removal of rocket fuel handler's clothing outfits. The rocket fuel handler's clothing outfits are not stored at the launch complex. 1-13. The blast lock structure provides blast-protected entry from the access portal to the hardened facility and between the control center and the launch silo. Four blast-resistant doors, interlocked in pairs, are manually opened and closed. The doors are secured in the closed position by hydraulically operated latches. Adjacent to each blast door, on each side of the wall, is a control station with OPEN and CLOSE (LOCK and UNLOCK at VAFB) push-buttons which engage or disengage the hydraulic latches. The blast doors are interlocked in pairs; 6 with 7, and 8 with 9. Pressing either push-button dc-energizes the control circuitry of the mating door, preventing the two doors from being opened at the same time. If normal hydraulic power fails, the latches can be operated by manual hydraulic pumps which override the Interlock feature. After MCL 3226, for blast lock entry from the access portal area, the push-button on the push-button-alarm light panel mounted on the LCCFC must be momentarily pressed at the same time the OPEN push-button for door No. 6 is pressed. A buzzer will sound when blast door 6 is open. The buzzer may be silenced by pressing the .alarm silence push-button.

ACCESS PORTAL.
The access portal (figure 1-4) is a rectangular, reinforced concrete structure, flush with ground level, which provides personnel entry to the launch complex. The portal contains a stairway leading to the outer door of the blast lock. A freight elevator is provided for movement of equipment down through the access portal and into the blast lock. A television camera, located near the first landing in the access portal, permits personnel identification by the missile combat crew commander (MCCC) from the control center. A telephone, located on the first landing of the access portal, permits verbal identification. After MCL 3226, OUTER ENTRANCE OPEN on the LCCFC will flash when the access portal sidewalk doors at grade are open.

ENVIRONMENTAL PROTECTION.
(See figures 1-3 and 1-4.) Electrical power, control, and communications circuits entering the launch complex are electromagnetically shielded from over-voltage surges which may be generated by natural phenomenon (electrical storms). Electrical interference filter groups are located on level 2 of the silo equipment area, in blast lock No. 202, on level 3 of the control center, and in the HF hard antenna silo.

CONTROL CENTER AIR CONDITIONING, HEATING AND VENTILATION SYSTEM.
The control center air conditioning system (figure 1-5) supplies air to the control center at a temperature of approximately 74 degrees F and a relative humidity of 55 percent maximum. Outside air is supplied through the intake shaft to the air conditioning unit. The air conditioning unit fan continuously circulates conditioned air to all areas within the control center. The control center air conditioning, heating, and ventilation system is controlled from the BM-1 control center heating and ventilating control panel (figure 1-6).

ACCESS PORTAL AND BLAST LOCK VENTILATING SYSTEM.
The access portal and blast lock ventilating system circulates outside air through the access portal, and conditioned air through the blast lock area. Conditioned air is exhausted from the control center, passed through the blast lock, the decontamination area, and out to the launch silo. This provides air flow from the control center toward the launch duct area to prevent the flow of toxic vapors through the cableway toward the control center.

LAUNCH DUCT AIR CONDITIONING SYSTEM.
The launch duct air conditioning system, in conjunction with the silo heating and evaporative cooling system, supplies conditioned air at a constant temperature and humidity to the launch duct. 1-20. Intake and exhaust fans provide air circulation and purge capability in the launch duct area. Purging is controlled automatically by the hazard sensing and warning system, but may be manually controlled when necessary. 1-21. Outside air entering the launch duct area is filtered by an electrical motor-driven roll-type filter located on level 3 of the launch silo between the intake blast valve and the air conditioning unit. A new filter media is automatically provided as needed; however, periodic changing of the roll is necessary.

CHILLED WATER SYSTEM.
The chilled water system is composed of the following major items: an expansion tank, supply pumps, a chilling unit, a mix pump, distribution equipment, heating and ventilating control panel BM-3, and various items of associated system equipment. 1-23. The chilled water system chills and circulates water from the water chillers to the portable hydraulic units, the after-cooler of the air compressor, the chilled water coils of the air conditioning units, and a cooling water mix pump. (After MCL 3259) Chilled water will also circulate through diesel engine lube oil-cooler. The system is automatically controlled by associated electrical and pneumatic components to maintain required water chilling and circulation. The system functions consist of circulation and control, refrigeration and control, and electrical control.

COOLING WATER SYSTEM.
The cooling water system is composed of the following major items: industrial water supply equipment, supply pumps distribution equipment, cooling towers, flow diversion equipment, and various items of associated equipment. (After MCL 3259) Cooling towers are not installed. 1-25. (Prior to MCL 3259) The cooling water system circulates water from cooling towers to the diesel engine lube oil cooler, and the water cooled condensers in the chilled water system. During normal circulation and control when the temperature of the water is above 50 degrees F, the water is cooled by CT101 and CT102. When the temperature of the water is less than +50 degrees F, the system circulates water through the 100, 000-gallon water storage tanks During the post-attack operation, the system is electrically and pneumatically controlled by the heating and ventilating control panels }3M and BM-3 1-25A. (After MCL 3259) he cooling water system will operate only during post-attack mode and circulates water from the 100, 000 gallon water storage tank to water condensers in chilled water system. The system is electrically and pneumatically controlled by heating and ventilating control panels BM and BM-3.

COMMERCIAL POWER.
Power for the launch complex is normally supplied by a commercial source. Maximum power available to operate the launch complex is 500 kva (750 kva at VAFB). Failure of commercial power will not affect launch capability. A standby power supply, designed to operate in the event commercial power fails, is located on level 3 of the launch silo. 1-28. To insure adequate power to the launch complex, a transformer, consisting of three sections located In a recessed transformer vault above ground, is connected by primary terminals through an underground conduit to the commercial power source. Provisions are incorporated in the high-voltage portion of the transformer to ensure that commercial power can be disconnected for maintenance.

STANDBY POWER.
If commercial power fails, standby power supply equipment provides power to the launch complex. This equipment consists of a diesel engine, a generator, a transformer, switches, cables and heating, cooling, and venting facilities for power generating equipment. The diesel generator consists of a six-cylinder diesel engine and one synchronous ac generator rated at 350 kw, with a dc exciter mounted on the stator housing. Both the generator and exciter are driven by the diesel engine. The generator rotor shaft is directly coupled to the engine fly wheel. The exciter is belt driven from the generator rotor shaft. 1-30. The diesel engine is supercharged and rated at 510 brake horse power at 900 rpm. To ensure starting reliability, the engine is equipped with a 480-volt immersion heater designed to maintain the engine water jacket temperature at +126(+8) degrees F during standby. Engine cooling is accomplished by an embullient type cooling system. An embullient cooling system is one in which the coolant is circulated through the system by a temperature differential. Engine oil cooling is accomplished by a water cooled lubricating oil cooler which maintains the oil temperature below +190 degrees F during engine operation. Heat from the lubricating oil is absorbed by cooling water metered into the cooler by the lubricating oil cooler temperature control valve. The fuel supply for the engine is contained in underground storage tanks connected to a 55-gallon engine fuel tank. 1-31. Switching from commercial power to standby power is accomplished by 480-volt switch gear (figure 1-7) which monitors both commercial and standby power sources. The switch gear controls the standby power source and automatically switches from commercial to standby. Manual switching control is provided for commercial to standby and standby to commercial. When a failure of commercial power is sensed, automatic controls send a signal to start the diesel engine. The diesel engine starts, attains operating speed, generator voltage comes up to normal, and a circuit breaker closes. Closing of the circuit breaker supplies power to the motor control centers (MCC). Normal time elapsed from sensing of commercial power failure to closing of the circuit breaker is 60 seconds or less. The standby power source may also be controlled by switches on the diesel engine control and instrument panel (figure 1-8) mounted on the engine, from the 480-volt switch gear, or from the FACILITY POWER CONTROL BOARD (FPCB), FACILITY POWER panel, located on level 2 of the control center.

PERMISSIVE CONTROL.
Permissive control is used to prevent damage to the diesel generator when power is switched from commercial to standby power. This is accomplished by three permissive control relays located in the control center, blast lock area, and missile silo. When the GENERATOR CIRCUIT BREAKER on the 480-volt switch gear is closed, contacts close, routing 120 vac from the standby power metering transformer to the permissive relays. The permissive relays have contacts in the control circuits of the equipment to be disabled, and remove control power when energized. Some of the disabled circuits can be energized by closing permissive switches located on the FPCB, MCC-1, and lighting panels throughout the launch complex. 1-33. The diesel engine immersion heater is de-energized when facility is on standby power. There are no provisions for manual operation. 1-34. When equipment is manually energized, the WATTMETER on the FACILITY POWER panel of the FPCB must be monitored to prevent the generator from becoming overloaded. The following equipment is dc-energized when facility is on generator power, but may be energized manually. Equipment energized at the PERMISSIVE CONTROL panel of the FPCB is not listed. a. Receptacle pit (except RP-1 lighting panel). b. Control center lighting panel, CC-2A (keyswitch override). c. Cableway and access portal lighting panels, CW-1 and AP-1 (on distribution panel No. 1). d. Launch silo lighting panel, LS-6 on silo level 6 (kevswitch override).

FACILITY POWER CONTROL BOARD.
The FPCB panels (figure 1-9) consist of pushbuttons, indicators, controls, and meters which control and monitor commercial and standby power, propellant transfer operations and facility water supply. Panels located on the FPCB are as follows: FACILITY POWER panel, which controls and monitors both commercial and standby power; PERMISSIVE CONTROL panel, which allows operation of designated items of facility equipment; P. T. S. UNLOADING CONTROL panel, which controls and monitors propellant transfer operations and deflector fill and drain operations and FACILITY WATER SYSTEM panel, which monitors the facility water system. A LAMP TEST pushbutton on the FPCB allows the indicators on all panels to be tested. A communications jack permits wire-type communications between the FPCB and other areas of the launch complex.

MOTOR CONTROL CENTERS.
See figures 1-10 and 1-11.) MCC-1 and MCC-2, located on silo level 3 and control center level 3 respectively, serve as power distribution centers and contain equipment for electrical motor control. Each MCC is divided into panels containing circuit breakers, combination circuit breaker and motor starters, magnetic contactors, and control transformers. MCC-1 also contains a lighting transformer and lighting panel (LS-3) not found on MCC-2. 1-37. Circuit breakers are plug-in units with stab connectors which clip to vertical buses within the MCCs. The breakers provide overcurrent and short circuit protection for the power circuits. Each breaker is provided with a switch handle and escutcheon plate located on the front of the individual panel. 1-38. The combination circuit breaker and motor starter is a plug-in unit with stab connectors that clip to vertical buses within the MCCs. The breakers are similar to those described in paragraph 1-37; except that the motor starters are magnetically operated, have an overload protection device, and a manual RESET pushbutton located on the front of the individual panel. The motor starters are operated by a control transformer within the MCCs or by external 120-vac control circuits. When excessive current flows in the power circuit to the motor, the overload contacts open, de-energizing the motor starter which removes power from the motor. The protection device is reset by pressing the RESET pushbutton. 1-39. Magnetic contactors are magnetically operated switches used to close or interrupt electrical circuits. Contactors are provided for electrical motors where overload protection is not needed or is provided separately, and to connect lighting loads to the power source. The main line contacts open when the control circuit to the magnetic coil is interrupted. Control transformers supply 120-vac control power to the motor starter control circuits.

WATER SUPPLY SYSTEMS.
(See figure 1-12.) 1-41. Water at operational complexes is supplied by deep wells or a commercial source. The water is chemically treated, softened if necessary, and stored in a 100,000-gallon: tank located within the silo area between levels 3 and 6. 1-42. Control of the water system is maintained by both automatic and manual controls. These control the storage tank water level, water flow, isolation of water system, and detect over-pressurization of the supply line. 1-43. Indicators that monitor water supply, water storage external to silo, and water treatment are located on the FACILITY WATER SYSTEM panel of the FPCB. The SILO WATER SUPPLY LOW indicator, on the LCCFC lights amber when the water level in the 100, 000-gallon tank falls below the 242 foot level. The indicator will remain lighted until the water level is restored above the 242 foot level. Level indicator LI-1, located on the 100, 000-gallon storage tank silo level 6, provides a visual indication of water level in the tank. The gauge indicates green from the low water level through the high water level and red for a low level alarm or overflow condition. After MCL 3239 SILO WATER SUPPLY LOW indicator on LCCFC will flash when the water level is 3 inches below the outlet, indicating a probable overflow condition.

FIRE WATER SYSTEM.
The fire water system is controlled during commercial power utilization by the P-1 FIRE WATER PUMP selector switch on MCC-1. During standby power utilization, the system is controlled by FIRE PUMP P-i ON and OFF pushbuttons on the PERMISSIVE CONTROL panel of the FPCB. The fire water system supplies water to the launch duct spray units and to other water and foam spray units throughout the launch complex for control of fires. If Fire Water Pressure Controller PC-lS should malfunction while on commercial power the fire water pump can be turned on by pressing FIRE WATER PUMP P-1 ON pushbutton indicator on the FPCB. When the fire water pump is turned on from the FPCB, the FIRE WATER PUMP P-1 ,OFF pushbutton must be pressed to stop pump operation.

FIRE PROTECTION AND PREVENTION SYSTEM.
The fire protection and prevention system is composed of the engine spray and sound attenuation systems, which are gravity fed from the 100,000-gallons silo storage tank. When fire is sensed in the Stage I missile engine area, the system supplies water to the engine spray nozzles, which direct the water into the Stage I missile engine compartment. During Stage I missile engine firing, the system supplies 9,000 gallons of water per minute (12,000 gallons per minute at VAFB) to the sound attenuating deluge header. This water is sprayed into the launch duct by the sound attenuating deluge nozzles for attenuation of sound. At VAFB, a thrust chamber spray is activated by the missile combat crew in the event abort occurs.

DOMESTIC WATER SYSTEM.
The domestic water system distributes water to all emergency showers and eyewash fountains; to the fuel and oxidizer hardstand hose connection valves; to the depressed fuel and oxidizer hardstand hose connection valves (VAFB); to the industrial water system; and to the control center facility plumbing. (AFTER MCL3284) it is also distributed to fuel propellant storage facility.

INDUSTRIAL WATER SYSTEM.
The Industrial water system provides make-up water, under pressure, to repinish losses In the chilled water system and cooling water system, humidifying water to the launch silo heating and evaporative cooling system; diesel engine cooling water to the power generation system; and pressurizing water to the fire water system. During commercial power utilization, the industrial water system is pressurized by the domestic water system. When the launch complex is in the hardened condition, the system is pressurized by the industrial water pump.

FIRE WATER RECIRCULATION SYSTEM (After MCL 3315).
The fire water recirculation system allows reuse of the fire water (during a fuel spill only) by returning it to the hardwater storage tank through use of the sump pumps. Normal sump operation shall require the recirculation valve to be closed prior to pumping topside and reopened after the sump is empty.

FIRE WATER CONTROL SWITCH (After MCL 3316).
The Fire Water Control Switch-1 (FWCS-1) on RC-22 allows permissive control of the fire in engine, fire launch duct and explosive fuel launch duct sprays when in the MANUAL position. Then the EWCS-1 is in the AUTO position, the fire in engine, fire launch duct, and explosive fuel sprays will come on automatically as they are required.

PROPELLANT TRANSFER SYSTEM.
The propellant transfer system (PTS) consists of both fixed (launch complex) and mobile maintenance ground equipment (NGE). Functions of the PTS are to load and unload the missile tanks, purge the missile tanks and transfer lines, and to initially pressurize the missile tanks to flight pressure. Normal PTS operations are controlled from the mobile propellant control trailer. Emergency propellant unloading operations can be controlled from the P.T.S. UNLOADING CONTROL panel on the FPCB. Fuel and oxidizer are delivered to the launch complex in tank trucks and transferred from the tank trucks through portable hoses to the fuel andoxidizer holding trailers. The propellants are then conditioned and transferred to the missile tanks where they are stored. Gaseous nitrogen is delivered to the launch complex in a tube trailer and transferred through hoses to the holding trailers or facilities systems to perform purging, and pressurizing operations. The missile propellant tanks are prepared for loading by pressure testing and purging the PTS; manually connecting the vent and fill-drain disconnects to the missile; leak checking the missile tanks; purging the missile fuel tanks; and loading, adjusting, and conditioning propellants in the holding trailers.

Propellant loading is accomplished by gravity flow of the propellants from the holding trailers to the missile tanks. The fill-drain disconnects are then manually disconnected from the missile and connected to the pressure-drain disconnects, the missile tanks are pressurized with gaseous nitrogen, the vent disconnects are removed from the missile and stored on the silo wall, the propellants remaining in the facility lines are pressure drained to the holding trailer, the propellants in the holding trailers are drained to the transport trailers, and the mobile MGE is disconnected and removed from the launch complex.

Propellants are unloaded from the missile if certain airborne components are to be replaced or repaired, or if it is necessary to remove the missile from the silo. The PTS is prepared for unloading operations by connecting, inspecting, pressure testing, and purging various items of mobile and fixed equipment. Propellants are then unloaded from the missile to the holding trailers. Gaseous nitrogen from the nitrogen tube trailer is used to pressurize the missile tanks during the unloading to ensure a positive head pressure to prevent a negative tank pressure as propellant level decreases. Unloading stops when liquid sensors in the facility are uncovered after the missile tanks are empty.

Emergency unloading facilities are provided in the event fuel or oxidizer must be unloaded. This Is performed by manually connecting the vent and fill-drain disconnects to missile and operating switches on FPCB. Prior to MCL 3263, the capability exists to transfer propellants from missile to fixed dump tanks by unloading pumps. After MCL 3263, the fixed dump tanks are no longer used, and propellant must be pumped from missile to mobile tank equipment. Gaseous nitrogen from the tube trailer is used to pressurize the missile tanks during unloading to ensure a positive head pressure to unloading pumps and prevent a negative tank pressure as missile tank propellant level decreases. When mobile MGE becomes available, it is connected and propellants remaining in facility lines are pressure drained to holding trailers.

Propellant pump rooms, located on silo level 8, contain fixed equipment used for transfer of propellants. Fuel or oxidizer unloading pumps and safety relief valves are installed in pump rooms to transfer propellants from missile tanks to holding trailers during normal transfer operations. Pump room indicators give direct indications of nitrogen pressure in missile tanks during transfer of propellants. Valves contained in pump rooms are used for isolation, draining, bypassing, bleeding, and venting various parts of the system. Figures 1-13 and 1-14 illustrate equipment contained in propellant pump rooms. (After MCL 3284) Propellant transport trailer storage facilities are designed to store oxidizer fuel transport trailers when not in use. Each facility has an external equipment building which contains vapor sampling system equipment. Both fuel and oxidizer facilities are equipped with toxic analyzers and automatically controlled vent fans. Additionally, the fuel facility contains an explosive analyzer which initiates automatic corrective action (water spray) when a high explosive level (20,000 PPM) is detected. Each TITAN unit has one fuel and one oxidizer storage facility.

HYDRAULIC POWER UNIT HS-1.
Hydraulic power unit HS-1 (figure 1-15), located on silo level 1, consists of an electric motor driven pump, related components, piping, and a hydraulic fluid reservoir. Twelve accumulators (figure 1-16) are provided to store the hydraulic power. 1-58. Hydraulic power is produced by pumping hydraulic fluid to the accumulators, which are pressurized with nitrogen gas. The accumulators retain the hydraulic power until needed for operation of the silo closure door locks, jacks, and drive unit. Controls and indicators for HS-1 are located on silo levels 1 and 3, and in the control center.

HYDRAULIC POWER UNIT HS-2.
The hydraulic power unit HS-2 (figure 1-17), located on silo level 6, consists of an electric motor driven pump, a reservoir, strainer, filter, valves, switches, and indicators. An accumulator is provided to store the hydraulic power. 1-60. Hydraulic power is produced by pumping fluid from the reservoir, with the electric motor driven pump, to the accumulator until pressure reaches 3500 50 psig. The accumulator is pressurized with nitrogen gas supplied by the nitrogen receiver, and retains hydraulic power until needed for operation of the retractable platforms and silo blast valve systems. 1-61. The retractable platform locks are operated by compressed air supplied by the air receiver. The air receiver is located adjacent to HS-2 accumulator, and receives air from the facilities air supply.

HYDRAULIC POWER UNIT HS-3.
Hydraulic power unit HS-3 (figure 1-18), located beneath the blast door control panel in the blast lock area, consists of a motor driven pump, hand pump, reservoir, filters, and valves. An accumulator is provided to store the hydraulic power. 1-63. During operation, the motor driven pump starts automatically when hydraulic pressur Idrops below 835 (±15) psig, and charges the accumulator to 1475 (±15) psig. The hand pump is used to charge the accumulator if the motor driven pump fails. Hydraulic power is stored in the accumulator until needed to operate the blast doors and the blast damper assemblies.

HYDRAULIC POWER UNIT HS-4.
Hydraulic power unit HS-4 (figure 1-19), located on level 2 of the control center, consists of a hydraulic hand pump, reservoir, accumulator, and electrical and hydraulic components housed in a metal cabinet. 1-65. The accumulator is nitrogen precharged to 500 psig and is pressurized to 1000 psig when the hand pump is operated. The hydraulic power is stored by the accumulator until needed for manual or remote operation of the control center blast valve BV-5.

HAZARD SENSING AND WARNING SYSTEM.
1-67. Hazard sensing and warning equipment is located throughout the launch complex for sensing, warning of personnel, propellant vapor level, and fires. The sensing and warning system consists of fuel vapor, oxidizer vapor, and Lire sensors; vapor detector annunciator panel; fuel and oxidizer vapor sensing racks; and associated circuitry.

FIRE SENSING EQUIPMENT.
When a fire sensor detects a temperature of approximately +140 degrees F, associated circuitry activates the applicable indicator on the LCCFC, turns on water or foam spray when automatic corrective action is provided, shuts down fans, and sounds warning horns throughout the launch complex. Fire sensing circuits are located in the control center, Stage I missile engine area, diesel engine and diesel fuel service tank areas, launch duct, and oxidizer and fuel pump rooms.

FIXED VAPOR SENSING EQUIPMENT.
(Prior to MCL 3252) Fixed vapor sensing equipment consists of an oxidizer vapor detector, a fuel vapor detector, a vapor detector annunciator panel, and associated sensing devices located throughout the silo area. The equipment detects, monitors, and records the concentration of fuel vapor and oxidizer vapor in designated areas of the silo. Vapor sensing devices initiate sounding of warning horns and automatic corrective action such as purging and turning on water spray. When a fuel vapor concentration or an oxidizer vapor concentration of 5 PPM is sensed, associated circuitry lights the applicable indicator on the LCCFC. As higher concentrations of vapor are sensed, the purge and water spray systems are activated, and applicable indicators on the LCCFC are lighted. (After MCL 3252) Fixed vapor sensing equipment consists of an oxidizer, fuel vapor detector, vapor detector annunciator panel, and associated sensing devices located throughout the silo area. The equipment is normally set to sample EF-102 exhaust (silo level 5), but other silo areas may be manually selected. The equipment detects and monitors concentration of fuel vapor and oxidizer vapor in designated areas of silo. Vapor sensing devices initiate sounding of warning horns and automatic corrective action such as purging and turning on water spray. When a fuel vapor concentration or an oxidizer vapor concentration of 5 PPM is sensed, associated circuitry lights the applicable Indicator on LCCFC. As higher concentrations of vapor are sensed, purge and water spray systems are activated, and applicable indicators on LCCFC are lighted. When SELECTOR switch is set to sample the fuel pump room or the silo equipment area, LCCFC alarm indications and automatic corrective action for explosive fuel launch duct are disabled. 1-70. when launch duct spray, engine spray, sound attenuating deluge, or fuel pump room spray Is activated, a signal is sent to the vapor sensing equipment, de-energizing the toxic sampling solenoid valves to prevent water from being drawn through the sensing lines. This Is referred to as water lockout. During water lockout the vapor detection equipment is sampling for toxic and explosive vapors on silo equipment area level 6 only, Any meter indications or light indications which occur on the VDAP or LCCFC are a result of vapors on silo equipment area level 6. The system remains in water lockout I for approximately two minutes after the sprays have been turned off, then returns to the normal sampling mode. 1-70A. (After MCL 3284) On those complexes containing propellant storage facilities, a vapor sensing sampling system provides continuous monitoring and automatic corrective action. A vapor sensing alarm panel (VSAP) is located on the side of the FPCB in the control center. A TOXIC ALARM indicator lights and a buzzer sounds when vapor concentrations in excess of TLV are detected. Automatic circuitry controls the storage facility fan and in fuel facilities only activates water spray when explosive levels (20,000 PPM) of fuel are detected.

MAINTENANCE GROUND EQUIPMENT (MGE).
1-72. MGE Is located at the squadron maintenance areas (SMA) and at launch complexes, and is used to place and maintain launch complexes in an operational condition on a scheduled or as required basis. Major items of MGE are described in the following paragraphs.

PORTABLE MAINTENANCE GROUND EQUIPMENT.
1-74. Various items of maintenance ground equipment are portable and are used above and below ground at the launch complexes. 1-75. PROTECTIVE CLOTHING. Protective clothing is utilized when personnel are required to investigate or perform operations in certain hazardous or potentially hazardous areas. Protective clothing is described in paragraph 1-262. 1-76. SAFETY NETS. Safety nets are installed over launch duct openings for personnel safety when the missile is removed and work platforms are lowered. 1-77. ENGINE ALIGNMENT KIT. The engine alignment kit is used to set the exact distance required between the booster actuators, roll nozzle actuators and sustainer actuators; and to assure required pitch, yaw, and roll control of the missile. 1-78. MISSILE POSITIONING SET. The missile positioning set is used to transport a missile to the launch complex and install both stages In the launch silo. The set consists of missile trailers, slings, lifting adapters, lines and special tools. The missile positioning set is used in conjuction with prime movers and the missile handling crane. 1-79. MAINTENANCE PLATFORMS. Maintenance platforms are installed in various missile compartments and the launch duct when needed for special maintenance functions. Maintenance platforms Include Stage I engine compartment work platforms, Stage TI engine compartment work platforms, a RV inspection ladder, and work stands. 1-80. MOBILE HYDRAULIC PUMPING UNIT. The mobile hydraulic pumping unit Is used to flush, proof pressure test, bleed, and fill missile hydraulic systems in the silo after maintenance has been performed. The pumping unit Is positioned at level 7 of the launch silo for Stage I and at level 3 of the launch silo for Stage II, and is connected to missile hydraulic disconnects by flexible hoses. 1-81. MOBILE PROPELLANT TRANSFER SYSTEM EQUIPMENT. Mobile PTS equipment Is used at the launch complex for missile propellant loading and unloading. The equipment includes transport trailers, holding trailers, a conditioning trailer, a control trailer, a tube trailer, portable oxidizer vapor burner set, portable shower and eyewash fountains, fuel and oxidizer unloading pump kit, safety relief valve kit,portable fuel and oxidizer filters, fuel and oxidizer missile tank pressurization kit, the propellant vapor scrubber system (PVSS) and the portable foam vapor suppression system (PFVSS). 1-82. A PTS structural pressure control unit provides the signal conditioning to connect the low level output of the tank pressure transducers into a 28 vdc signal that will activate the relays in RC22 to control th loading/unloading pumps. 1-83. A pressure transducer monitor system calibration box provides an accurate adjustable voltage from 0-5 vdc that simulates the tank pressure transducer output for use in calibration of the monitor unit and PTS structural pressure control unit as well as in system troubleshooting and maintenance. 1-84. MONITOR-SIMULATORS. Missile and facilities monitor-simulators are used at the launch complex to verify proper operation of the launch control set (LCS). The simulators simulate all missile and facility responses necessary to exercise the LCS in all operating modes. Simulators perform related functions and cannot be used individually. 1-85. The missile monitor-simulator simulates all necessary missile and RV static and dynamic responses required by the LCS to perform various functions. Switches are provided on the simulator for simulating all probable missile and RV system malfunctions. The simulator is positioned on level 3 work platform and connected to the electrical umbilicals by adapter cables. 1-86. The facilities monitor-simulator simulates target functions, inertial guidance system (IGS) functions, and facility functions required by the LCS to perform its various functions. Switches are provided to simulate malfunctions in the target system, the IGS, and the facility. Switcies are also provided for simulating facility hazards. The simulator is positioned on level 2 of the control center adjacent to the LCCFC, and connected to operating ground equipment (OGE) cabling by adapters. 1-87. With both simulators installed, the LCS is capable of readiness operation, launch sequence, missile verification, launch verification, and missile/launch verification.

NON-PORTABLE MAINTENANCE GROUND EQUIPMENT.
1-89. Non-portable MGE includes test equipment, cleaning equipment, maintenance tools and stands, liquid storage, and other electrical and tnechan-ical items utilized within the SMA. 1-90. OPERATING GROUND EQUIPMENT. 1-91. The 0GE, located at the launch complexes, maintains the missile in a constant state of launch readiness. Primary items comprising the 0GB are the LCS, missile systems fault locator (NFL), and the coded switch system (CSS). Other 0GE supporting the operation of the missile includes the missile guidance alignment-checkout group (MGACG), battery power supplies, 28 vdc power supplies, and communications systems. During readiness monitoring, personnel at the launch complex utilize the LCCFC to continuously perform readiness monitoring of the missile and systems directly supporting launch. The missile combat crew performs malfunction isolation utilizing the LCCFC, CMG, MFL, MGACG and power distribution control (PDC). During a tactical operation, personnel at the launch complex utilize the CSS and the LCCFC to receive alert or strike commands, confirm missile status to the wing command post (WCP), achieve a launch enabling signal, receive target information, initiate launch sequence of the missile, and monitor the missile launch. 1-92. Major items of OGE are described in the following paragraphs. Other items will be included in the paragraphs describing the missile systems.

LAUNCH CONTROL SET.
(See figure 1-20.) The function of the LCS is to monitor, display, and control signals pertaining to readiness, launch, verification, targeting, and hazard status, and to control and monitor power for the weapon system. The LCS consists of three independent sub-systems; the LCCFC, the CMG, and the PDC.

LAUNCH CONTROL COMPLEX FACILITIES CONSOLE.
The LCCFC (figure 1-21) controls and monitors readiness, facilities and launch sequence. It includes all the parts and subassemblies, other than logic, required to monitor and identify hazardous conditions which may exist. Controls are provided for the activation of damage control equipment. The LCCFC consists of a base and a two-panel mounting section. The console has two center drawers and an access door on each leg section. A communications panel, containing necessary controls and indicators for maintaining communication, is also provided. Cables enter the console through the legs to a connector panel directly behind the console panel. The desk top has a writing area with a phone dial mounted on the right-hand side, and operator's headset jacks mounted on both sides of the knee well. (After incorporation of TCTO 21M-LGM25C-728.) A propellant tank pressure monitor unit which consists of digital meter reading PSIG and a pushbutton switch for selecting various propellant tanks is mounted on top of the console panel section. After MCL 3226, a pushbutton alarm light panel is mounted on the LCCFC left arm which has indicators for an open blast door 6 or 9 and a pushbutton to enable opening of blast door 6 from the access portal area. A buzzer will sound when blast door 6 is open. The buzzer may be silenced by pressing the alarm silence pushbutton,

1-96. The console panel is divided into three sections: LAUNCH CONTROL AND MONITOR, READINESS CONTROL AND MONITOR, and FACILITIES CONTROL AND MONITOR. The LAUNCH CONTROL AND MONITOR section contains switches to lock out the system, select a target, initiate a launch, shutdown and reset. It also contains indicators to monitor the prelaunch, missile and launch verification, and launch sequence functions. The READINESS CONTROL AND MONITOR section contains operational guidance system indicators, power distribution indicators, missile status indicators, and RV indicators. The FACILITIES CONTROL AND MONITOR section contains pushbutton-indicators and indicators which monitor and control hazards and abnormal conditions which may exist throughout the launch complex. Flashing red indicators denote fire and toxic vapor hazards; the associated spray, foam, and purge indicators denote corrective action taken. Amber and red indicators indicate other hazardous or abnormal conditions which require immediate attention. The function of, and corrective action for each indicator on the LCCFC is contained in figure 5-1. LCCFC switches are of three types. Momentary switches remain on only as long as they are pressed. Push-push switches are turned on or off by pressing, then pressing again to release. The key-lock switch is covered by a switch guard and sealed for security. This seal must be broken before the switch guard is lifted for insertion of the launch key. The key is inserted in the key-lock switch, turned clockwise, held momentarily and released. Spring action returns it to off. 1-97. Indicator lights on the LCCPC are coded as follows:
 * Green - go or ready.
 * Red - no-go or not ready.
 * White - in process or operating.
 * Amber/flashing amber - caution, potential hazard, or marginal.
 * Flashing red - hazard.

CONTROL-MONITOR GROUP.
The CMG (figure 1-22) monitors and controls prelaunch, launch, readiness, and verification mode signals, and monitors target and facilities signals. The single rack of the CMG-1 (LAUNCH SEQUENCE), CMG-2 (FACILITY AND TARGET SELECTION), CMG-3 (RE-ENTRY VEHICLE MONITOR), and CMG-4 (SIMULATION CONTROL AND OVERRIDE MONITOR). Cable entry is through the bottom of the rack.

1-99. The CMG-1 chassis contains the logic required to control launch. The logic structure contains circuit assemblies to perform the necessary And, Or, Inversion, Lock-Up, and Time Delay operations. Logic is performed by solid state devices or relays operating from a 28 vdc power supply.

1-100. The CMG-2 chassis contains the logic required to control target, facilities, and damage control. The logic structure contains circuit assemblies to perform the necessary And, Or, Inversion, Lock-Up, and Time Delay functions. The logic is performed by solid state devices operating from a 28 vdc power supply.

1-101. The CMG-3 chassis monitors RV status, target and burst selection, and verifies that either ground or air burst has been selected. Additionally, the CMG-3 chassis provides control for periodic pressure and continuity monitoring of the warhead and provides target burst control.

1-102. The CMG-4 chassis contains circuits required to provide manual permissive control and indication for the electrical simulation of opening the silo closure door, locking the thrust mount, and turning on the water deluge system during a launch verification. This chassis also contains th circuitry required for the override of the silo closure door. In an actua launch sequence, the CMG-4 manual permissive control is disabled by the presence of the 28 vdc ordnance-bus signal from CMG-1. CMG-4 also contain; circuitry, controls and indicators required to perform a missile ordnance circuit impedance test. The ordnance circuit impedance test will be performed prior to any IGS up-mode from off to higher modes, missile verification, launch verification, or any missile hydraulic pump run.

POWER DISTRIBUTION CONTROL.
The PDC (figures 1-23 and 1-24) contains power and logic switching circuits, interface termination provisions, power protection and distribution circuits, monitoring provisions, and checkout provisions. There are two racks in the PDC, one containing functional circuits (figure 1-23) and the other containing contactors and circuit breakers (figure 1-24). Both racks have cable entry through the bottom. Functional circuitry is divided into three panels consisting or PDC-1 (VOLTAGE MONITOR) PDC-2 (POWER SEQUENCE) and PDC-3 (CONTROL). The PDC-1 chassis contains seven solid state component boards which together perform four independent functions. The PDCpanel contains relay logic to control the power during readiness, checkout, or launch mode The logic is mounted on a single chassis composed of modules. The PDC-3 chassis contain logic driven relays, switches, and meters to monitor and control the power supplies used ir the OGE. A single module, extending across the width of the chassis, is used as a mountin for the relays. An ac-dc voltmeter and eight pushbutton-indicators are mounted on the pane so that voltages of power supply No. 1, power supply No. 2, battery power supply No. 1, battery power supply No. 2, readiness bus, transient bus, and faciltities phase A can be monitored. The STATUS AND CONTROL section provides control and monitor of power sources.

MISSILE SYSTEMS FAULT LOCATOR.
The missile systems fault locator MFL (figure 1-25) checks missile equipment in conjunction with the CMG, LCCFC, and PDC. The MFL is capable of isolating malfunctions to replaceable units in the missile, of logic level decisions, of simulating missile functions and evaluating missile outputs, and of self testing.

1-105. The MFL rack is composed of four individual, yet dependent, chassis. The MFL-1 (STIMULATOR MONITOR) chassis provides autopilot stimulus, travel position switch excitation voltage,checks valve drive amplifier output, and complete launch checkout. The MFL-1 front panel contains 34 indicators and a LAMP TEST pushbutton. The MFL-2 (CONTROL) chassis provides program control and selection for the MFL, indicates status of no-go indicators, and accomplishes critical checkout prerequisites and requisites. The front panel of the MFL-2 chassis contains a MFL status indicator; 3 mode selection pushbutton-indicators; 3 pushbutton-indicators for controlling power, program advance, and program reset; 2 component replace indicators; 25 no-go indicators; 4 spare indicators; and a LAMP TEST pushbutton. The MFL-3 (LOGIC ANALYZER) chassis verifies missile statu5 and isolates missile malfunctions to a replaceable component. The front panel of the MFLis composed of 34 system status indicators, and a LAMP TEST pushbutton. Te fourth chassis (not illustrated) contains an air cooler system to provide cool air for the other three chassis.

1-106. The MFL is functionally isolated from the LCS except when performing a checkout. When the MFL is disconnected, a launch connected signal is sent to the CMG.

1-107. The MFL is capable of operation in both the missile verification and launch verification modes. The missile verification mode checks operation of the flight control system, including the airborne hydraulic system. The launch verification mode checks the ability of the LCS to follow a normal launch sequence by checking recognition by the CMG of proper launch conditions. 1-108. Functional signals, grouped according to inputs and outputs, are displayed on the front panel of each chassis when an operation is performed on the signal. A test-timeexpired signal will be indicated if a sequence is not completed in the allotted time and a missile malfunction has not been indicated. In the event of MFL power failure, the system will return to the ready condition.

SIGNAL FLOW.
LCS signal flow during readiness monitoring is displayed by figure 1-26 and signal flow during launch sequence is displayed by figure 1-27. For detaile information regarding signal flow refer to T. 0. 21M-LGM25C-2-11.

CODED SWITCH SYSTEM (CSS).
The primary function of the CSS is to prevent an unauthorized or inadvertent missile launch. This is accomplished by locking the Stage I engine, subassembly 2 oxidizer buttérfly valve in the closed position. To unlock the butterfly valve and initiate a launch sequence, a valid operate code must he entered into the CSS, removing the launch-disable signal and providing a launch-enable signal. The status of each butterfly valve lock in the missile wing is monitored at the wing command post. The CSS (figure 1-28) consists of the following major components: a. Butterfly Valve Lock (BVL). b. Butterfly Valve Lock Control (BVLC). c. Butterfly Valve Lock Status Encoder. d. Butterfly Valve Lock Status Decoder and Display. e. Electronic Command Signals Programmer (PROGRAMMER). NOTE : VAFB does not have the BVL Status Encoder or BVL Status Decoder and Display portion of the CSS. All reference to this equipment, herein, does not apply at VAFB; however, all other portions of the CSS do apply. Refer to T. 0. 21M- LGM25C-1-1 for CSS information and equipment peculiar to VAFB only.

BUTTERFLY VALVE LOCK.
The BVL is mounted on the Stage I engine, subassembly 2 oxidizer butterfly valve. The BVL consists of an electrically driven lock on the valve diaphragm shaft, which locks the valve in the closed position until a valid operate code is entered at the BVLC. In the locked position a launch sequence cannot be initiated. The BVL also consists of code memory/code processing electronics, status monitoring electronics, a security enclosure, a secondary locking mechanism, a 36-hour timer maintenance safe capability and an internal battery power source that retains memory and operates the penetration detection and secondary locking circuits in the event readiness power is removed. 1-113. Security enclosure and secondary locking mechanism. To prevent unauthorized enabling of the system by manual means, the BVL contains two explosive charges which activate the secondary lock. Any attempt to remove the BVL cover and gain access to the primary locking mechanism will result in an explosive activated secondary lock system which locks the driving shaft of the Stage I engine, subassembly 2 oxidizer butterfly valve in the closed position. 1-114.	perate attempts limitations. To eliminate an unauthorized trial-and-error method of entering operate codes to open the locking mechanism and enable s launch sequence, the BVL contains electronic circuitry that limits the number of times an operate code may be entered to seven. After the seventh attempt, the BVL circuitry will not accept any more tries. The only indication that the operate monitor counter in the BVL has been exceeded is at the WCP. 1-115. 36-hour timer. Should normal safing procedures fail, or power be removed for maintenance purposes such as ground isolation check, the 36-hour timer will render the BVL maintenance safe 36 +3 hours after power has been removed. The BV will require recoding after maintenance safe is achieved by the 36-hour method; therefore, maintenance functions requiring power removal must be kept to less than 30 hours if at all possible. Applying power to the BVL for three minutes reestablishes the full 36-hour wait time, if possible this should he done during long maintenance power downs at approximately 30 hours. Should the BVL become maintenance safe in this manner the WCP will be aware of the maintenance safe status immediately upon return of power and will notify the complex. A BVL recoth will be required.

BUTTERFLY VALVE LOCK CONTROL.
The BVLC is located in the top position of the CNG rack (figure 1-28). The BVLC contains the controls and indicators necessary to operate, test, and monitor the BVL. The BVLC also interfaces BVL status information (which is displayed in the WCP) with the Butterfly Valve Lock Status Encoder. Functions of the BVLC controls and indicators are listed in figure 1-29.

BUTTERFLY VALVE LOCK STATUS ENCODER.
The BVL status encoder is located in the ALOC and contains the necessary electronics to transmit the BVL status information to the WCP. The status word is transmitted over telephone lines. Although acknowledge-call functions are not associated with the CSS, the BVL status erzcbder circuitry provides for transmission of this information within the status word containing the CSS status information. BVL status encoder controls and indicators are shown in figure 1-28 and their functions are listed in figure 1-29.

BUTTERFLY VALVE LOCK STATUS DECODER AND DISPLAY.
The BVL status decoder and display is located in the command post control officers console at the WCP and contains the electronics necessary to decode and display the status of the CSS for each complex.

ELECTRONIC COMMAND SIGNALS PROGRAMMER.
The programmer is a portable piece of CSS equipment that does not remain connected in the system as the other components do. When an initial code or recode procedure is required the BVL must be disconnected from the system and the programmer connected directly to the BVL. The programmer transfers code words from a magnetic tape to the BVL memory. Depending upon the coding mode used the BUL is prepared for normal system operation or set up for maintenance functions. The three coding modes are:
 * Initial Code Mode - Used at initial installation of the BVL or to return BVL to operational status after it has been reprogrammed for a CST or maintenance function.
 * CST/Maintenance Recode Mode - Used to recode the BVL so a combined system test or maintenance procedure can be performed.
 * Recode Mode - Used to enter a new set of operate and test words (new tape from SAC). In addition to entering new SAC operate codes, the recode mode must be performed if the operate monitor counter has been exceeded (more than seven operate attempts). The recode mode is also limited to seven attempts to defeat the possibility of electronic scanning to access the lock. The BVL electronics will accept seven recode tries and then it will not recognize any further attempts. Therefore, seven attempts to recode should never be used because the lock cannot be safed by a CST/Maintenance recode to access the lock and reset the recode monitor counter. The only alternative, if seven attempts are made, is to power down the system (removing missile from EWO status) and wait for the BVL 36-hour timer to time out rendering the BVL maintenance safe.

Detailed operating procedures to program the BVL are contained in T.O. 21ML425C-2-26-1 and the programmer checkout and maintenance procedures are contained in T.O. 33D9-131-13-1. 1-120. CSS circuit breaker activation order. PDC circuit breakers 21 and 22 and COffl' PER circuit breaker on the BVLC must be set to ON prior to setting LOCK POWER circuit breaker on the BVLC to ON. Should power be applied to the BVLC with the BVLC OPERATE INITIATE switch /indicator energized and LOCK POWER circuit breaker on, the operate monitor counter would count using one operate try. Therefore, it is to be verified that TEST INITIATE and OPERATE INITIATE are not lighted before setting LOCK POWER circuit breaker to ON. If neither indicator is lighted, LOCK 140WER circuit breaker can be set to ON. Circuit breakers 23 and 206 control only the STATUS ENCODER and may be turned on or off in any order without regard to the condition of CB21, CB22, CONT POWER, or LOCK POWER.

28 VDC POWER SUPPLIES.
Two 28-vdc power supplies (PS-1 and P8-2), located on level 3 of the control center, convert 480-vac, 60-cps, 3-phase facility power to 28 vdc. The 28 vdc is the main source of operating power during readiness monitoring, missile verification, launch verification, and launch sequence. The 28-vdc output is remotely controlled and monitored by the PDC, and monitored by the LCCFC.

BATTERY POWER SUPPLIES.
In the event commercial power fails, the interval between power failure and the time that the auxiliary power generator takes the load is normally less than 60 seconds. During this period, two battery power supplies (BPS-1 and BPS-2) contained on level 3 of the control center supply power (PS-1/PS-2) to 0GE readiness and transient busses. If either 28 vdc power supply fails, the applicable battery power supply will supply power to the bus normally supplied by the power supply unit that failed. The battery power supply consists of battery cells, an automatii battery charger, switching equipment, and controls. For classified Information regarding battery power supply operation, refer to T.O. 21WLGM25C-1-2. The batteries used for emergency dc power consist of nickel- cadmium cells arranged and connected in series. The cells are contained in battery trays which allow visual inspection of the cell plates fluid reservoir, and fluid level. Battery chargers, designed to operate on 480-vac, 60 cycle power, are provided to charge the batteries. The charging cycle is such that a high charging rate is used at first, then, automatically, the rate of charge lowers until the batteries are fully charged. Chargers then switch to trickle charge, automatically maintaining the batteries in a fully charged condition. Any time the charge is disconnected by a load-demand signal, removal of the signal causes the chargers to resume the charging cycle. A manual disconnect switch is provided in the dc output load of the battery power supply to isolate the battery from its respective bus for maintenance.

THRUST MOUNT AND SHOCK ISOLATION SYSTEM.
(See figure 1-30.)

THRUST MOUNT.
The thrust mount is a welded box beam ring, manufactured in two sections and bolted together, which provides attachment points for securing the missile. Four missile support arms on the lower, inside periphery of the ring provide attachment points for the four missile longerons. Four cantilevered suspension arms on the outside periphery of the ring provide for attaching the thrust mount to the dampers and ball screw jacks.

SHOCK ISOLATION SYSTEM.
The shock isolation system supports the missile on the thrust mount and provides protection against shock of nuclear blast. Subassemblies that make up the shock isolation system are vertical dampers, horizontal dampers, ball screw jacks, and suspension spring assemblies. 1-130. Four vertical dampers reduce vertical motion of the missile and thrust mount. The vertical dampers are friction type, 14 inches in diameter, 114 inches long (fully extended), and have a stroke of 30 inches. The vertical dampers are locked up by spring loaded shuttles pressed into a slot in the damper shaft. The lockup system is actuated by pneumatically retracting the lockout pins. The system is unlocked with a Stokes tool. Vertical damper length may be adjusted *2 inches to achieve proper lockup position of the damper shaft. 1-131. Four horizontal dampers reduce horizontal motion of the missile and thrust mount. Operation and configuration of the horizontal dampers is similar to that of the vertical dampers. The dampers are 8 inches in diameter, 81 inches long (fully extended), and have a stroke of 18 inches. Length of the damper shaft may be adjusted ±2 inches to assure proper lockup position of the damper shaft. 1-132. Four ball screw jacks provide for raising, lowering, and leveling of the thrust mount. The jacks are attached to the suspension spring assemblies and to the suspension arms of the thrust mount. The jacks are extended or retracted manually by turning the ball screw jack handles. The jack handles must be turned approximately 80 turns for each inch the jack is extended or retracted. A counter above the jack input shaft records and indicates the number of turns of the jack handle, 1-133. The four suspension spring assemblies attach to the wall mounted support brackets and to the top of the ball screw jacks to support the missile and thrust mount. 1-134. The THRUST MOUNT SOFT indicator on the LCCFC indicates status of the thrust mount. When the indicator is lighted, the thrust mount is locked and in the soft condition. When the indicator is not lighted, the thrust mount is not locked and is capable of withstanding the effects of nuclear blast. During the launch sequence, the thrust mount is locked automatically by the lock-thrust-mount signal from CMG-l. When the thrust mount is locked, a thrust-mount-locked signal is received by CMG-1 and the THRUST MOUNT LOCKED indicator is lighted. Automatic capability for unlocking the thrust mount is not provided. THRUST MOUNT SOFT and THRUST MOUNT LOCKED indicators also light when locking is simulated by CMG-4.

INERTIAL GUIDANCE SYSTEM.
IGS OGE consists of the MGACG. This component, and the two components of the missile guidance set, the IMU and NGC, comprise the IGS. Figure 1-31 contains a functional diagram of IGS OGE.

MISSILE GUIDANCE ALIGNMENT-CHECKOUT GROUP.
The MGACG (figure 1-32) located on level 2 of the control center, is a three-and-one-half bay structure containing seven equipment drawers and a cable distribution cabinet. Equipment bays 2 and 3 have electrical equipment air coolers.

The MGACG controls tape loading and mode sequencing operations required to prepare the missile guidance set for flight. IMU coefficients and targeting information for three possible targets are read from punched tapes by the MCACG, recorded in the memory of the MGC and verified by the MGACG. The NGACC controls the sequencing of the IGS from the off mode, through the align and the ready mode. Remote commands can also be issued to the MGACG through the CMG by the LCCFC.Vertical and azimuth alignment of the platform is accomplished during the align and ready modes without an external azimuth reference. The ready mode is the normal operating condition of the IGS.

During all modes of operation, the system checks itself for any malfunction. These test modes check for alignment loop malfunction, calibrate the missile guidance set by calculating and recording changed IMU coefficients, and check the flight program and steering signal functions of the MGC. If a malfunction occurs, indicators on the MGACG show the system status and the area of malfunction. The MGACG provides remote indications of system status to the LCS. The system then issues remote commands to the IGS through the MGACG to select one of the three possible targets and to advance the IGS to the ready mode or through the launch sequence modes. The IGS must be in the ready or memory mode before the LCS can initiate a launch sequence. During the launch sequence, remote commands cause the IGS to reverify target selection and to advance from the ready mode through the memory mode, the countdown steering test mode, and the inertial mode. In the inertial mode, the INU platform is no longer earth-referenced and the flight program of the MGC is initiated.

ELECTRONIC EQUIPMENT AIR COOLERS
(figure 1-33) provide a flow to cooling air over the electronic equipment in the alignment-checkout group only when the control center air conditioning system experiences a failur. The normal mode of operation of the air coolers is to set the FRONT and REAR circuit breakers to the OFF position. I The SIGNAL DATA RECORDER (figure 1-34) punches coded information from the MGC onto tape to record operating conditions within the IGS. The GUIDANCE CONTROL INDICATOR (figure 1-36) controls target and IMU tapes loading and verification, provides manual and remote sequencing of IGS modes and test, and contains provisions for self-checking of its circuitry and indicators. The GCI also performs malfunction isolation and receives malfunction isolation information from the IGS.

The PUNCHED TAPE READER (figure 1-37) reads the target and IMU tapes at 40 characters per second and supplies digital information to the MGC through the GCI. A TAPE READER malfunction will be indicated by the GCI if the tape breaks or if the tape is not threaded properly when the punched tape reader is operated in the SPOOL mode.

COMMUNICATION SYSTEMS.
The communications systems provide a means for communicating between the Strategic Air Command (SAC), numbered Air Force (NAF), the WCP, ACPs and launch complexes and for communicating within launch complexes. The five major areas of the communications system are as follows: The following paragraphs provide information on the five major communications systems with emphasis on crew understanding of operating characteristics and interpretation of malfunction or alert light indications, to enable the crew to determine the effects of trouble on the communications and launch capability.
 * Intra-complex communications (direct lines, wire-type maintenance network (WTNN), radio-type maintenance network (RTMN), television monitor, and voice signaling system (VSS)).
 * Inter-complex communications (direct lines, dial lines, and inter. complex radio communications system).
 * External communications (primary alerting system (PAS), 465L equipment, 487L SLFC system, hf radio, and uhf radio).
 * Antenna systems (RTMN, inter-complex radio communication system, hf discage, hf hard, and uhf).
 * Power distribution.

INTRA-COMPLEX COMMUNICATIONS SYSTEM.
The intra-complex communications system provides communication within the launch complex. Intra-complex circuits include direct lines, a WTMN, an RTMN, and a TV monitor. Section III and T.O. 21M-LGM25C-2-18 (T.O. 21M-LGM25C-2-17 atVAFB) contain operating and checkout procedures and a detailed description of components.

DIRECT LINES.
Direct lines consist of a surface gate phone, portal phones, and an emergency reporting network. These phones provide direct signaling to the LCCFC and alternate launch officer's console (ALOC). Access to the phone Is from the LCCFC and ALOC by pressing the appropriate pushbutton-indicator on the communications panel. The emergency phones are located in the cableway areas, the decontamination area, and the blast locks. The emergency network enables personnel trapped in tunnels or between blast locks to call the LCCFC or ALOC to report hazardous conditions or damage. It also provides one-way signaling between the station telephones and the consoles. A call is made on all direct line phones by lifting the phone handset. This automatically causes a 60 impulse-per-minute flashing Indication at the LCCFC and ALOC, and activates a ringer at each console. For emergency network calls, the light flashes red at 120 impulses-per-minute. All wire lines and RTMN calls are automatically placed on hold when the emergency network is accessed at the LCCFC or ALOC. If a second emergency reporting network call is received, the EMERG NET pushbutton-indicator flashes red on a steady white background. The console operator cannot place an emergency network call on hold. If more than one call is received, the MCCC may speak to each by sequencing through the calls with the EMERG NET pushbutton-indicator. The direct line telephone instruments are standard commercial units, and are either wall or pedestal mounted in a waterproof cabinet. The gate and portal phones contain ringers, but are without dials. The emergency network phones have no dials or ringers.

WIRE-TYPE MAINTENANCE NETWORK.
This network is used for maintenance operations throughout the launch complex. Communications are on a partyline basis with all headsets connected into the network. The headsets are equipped with two dynamic earphones in padded, noise-attenuating earphone cups. The receiver is a dynamic, noise-cancelling type with the input fed to a transistor amplifier mounted within a case clipped to the belt. A volume control is located on the amplifier case for adjusting the receiver level. A push-to-talk switch is incorporated in the assembly to permit the reduction of extraneous noises on the network when used in high ambient noise level areas. The push-to-talk switch has a locking device which provides hands-free operation of the headset in low ambient noise level areas. Each headset assembly is equipped with a 25-foot retractable cord. A special 100- foot retractable cord is available for use by the crane operator during missile installation. The headsets used with the network are plugged into jack stations when communication with the control center is desired. The jack stations are both standard and special. Standard jack stations are not adaptable for use In an unusual environment, whereas special jack stations are explosion-proof or waterproof, or both. When using explosion-proof jacks, the plug is rotated 1/4-turn clockwise after insertion. The jack stations contain a signalling button for one-way signalling to the LCCFC and ALOC. All soft station jack cabling is routed through the wire protection and distribution cabinet for overvoltage protection. For exact location of jack stations, refer to T.O. 21M-LGM25C-2-18 (T.O. 21M-LGM25C-2-17 at VAFB). There is a special application WTMN headset on complex for use when wearing the emergency breathing apparatus at the LCCFC, ALOC, or ASCC. The headset, Part No. SK0034-0600-020, is used with the BioPak 45 Closed System Oxygen Breathing Apparatus. The BioPak 45 facemask has a built-in microphone with connector for connection to the headset. The BioPak 45 utilizes an audio amplifier with an on-off-momentary on toggle switch. The toggle switch typically must be cycled to the momentary position when the Radio Type Maintenance Network has been accessed at the console. The BIOPAK 45 console headset utilizes an audio amplifier with an ONOFF-MOMENTARY ON toggle switch. If a communications net cannot be accessed at the console, the toggle switch must be cycled to the MOMENTARY ON position while accessing the net.

RADIO TYPE MAINTENANCE NETWORK.
This network is used where a source of mobile communications is required. It may be used in all areas of the launch complex (including topside). It may also be used in the PTS Control Trailer and the Rocket Fuel Handlers Clothing Outfit (RFHCO) during Propellant Transfer Operations. Equipment consists of FM portable transceivers, a base station, and above/below ground antenna systems. Maintenance personnel with transceivers can communicate with each other via the base station located in the RAD-1 rack on control center level 3. The base station acts as a repeater during transceiver operations. Transmissions from one transceiver are received at the repeater at one frequency and re- broadcasted throughout the system on another frequency. Portable transceivers can only receive transmissions from the repeater.

Portable Transceivers. Transceivers are light weight units capable of operation with or without headsets. Each transceiver has a removeable, rechargable battery, capable of seven hours of operation based upon 10% transmitter operation, 10% receive and 80% standby operation. External, heliflex antennas are located at the top of each transceiver. There are two types of portable transceivers. The aluminum faced Type 1 transceivers are stored in the control center and will react to the Radio Net Override signal generated by either the LCCFC, ALOC or an operational PTS control trailer. The black faced Type 2 transceivers are used in the PTS control trailer and will not react to the Radio Net Override signal generated from the PTS control trailer, but can be overridden from the LCCFC or ALOC. A built in microphone is provided for non-headset operation. Transceiver controls consist of the following: Each transceiver has a transmit indicator (red) which confirms proper transmitter output. Loss of transmit indication will be the result of an override condition (refer to paragraph 1-158F) or a low battery. All transceivers contain a 30 second time out timer which limits the time each transceiver can continuously be on the network. A pause in any transceiver broadcast will reset it's timer.
 * Push-To-Talk (momentary pushbutton)
 * Tone Signal (momentary toggle)
 * Squelch (knob type)
 * ON/OFF-Volume (knob type)

TRANSCEIVER USE & STORAGE.
Ten transceivers are stored at each complex. Maintenance personnel whose tasks require more than six transceivers will bring additional sets from MIMS and will return them to MIMS when they leave the complex. Four transceivers will remain in the control center for Missile Combat Crew use. One individual on each team or group entering the silo will carry a transceiver. Type headset used, if any, is designated by the MCCC. The MCCC, however, may designate either the WTMN or the RTMN as the primary communication net. If the WTMN is designated as the primary net, the RTMN will serve as a communication safety backup unit. All complex transceivers, headsets and carrying cases will be stored on level 2 of the control center.

TRANSCEIVER BATTERY CHARGERS.
Two (6) unit battery chargers are located on level 2 of the control center. See T.O. 21M-LGN25C-2-18 (21N-LGM-25C-2-17 VAFB) for charging instructions.

TRANSCEIVER OPERATION.
A call, to the control center console from the transceiver is initiated by a momentary press of both the TONE SIGNAL toggle switch and the PUSH-TO-TALK pushbutton. This causes a modulated tone to be transmitted from the transceiver to the operating repeater at the base station. The base station in turn signals the LCCFC and ALOC. RADIO TYPE MAINT NET indicator will flash on consoles along with a bell indication when signaled by a transceiver. Transceiver to transceiver communication is initiated by push-to-talk (no headset) or VOX (with headset) commands.

BASE STATION.
The RAD-1 Rack on control center level 3 contains the RTMN base station. Equipment included in the base station are as follows:
 * 2 repeaters (1 standby, 1 operational)
 * 1 Control and Transfer Assembly
 * 1 Power Supply
 * 1 Back up Battery Assembly (minimum of 8 hours operation)
 * 1 Duplexer
 * 1 Power Splitter
 * 1 Switch Panel

RTMN OVERRIDE.
The ALOC and LCCFC maintain priority control over the RTMN system by the use of the RADIO NET OVERRIDE pushbutton on the communication panel of each console. When the RADIO NET OVERRIDE pushbutton is pressed and held on either communication panel, transceiver to transceiver communication is cut-off. At this point all transceivers on the network will only receive console transmissions. When the PTS Control Trailer is operational on the complex during propellant transfer operations, the team chief in the trailer also has an override capability to cut-off transceiver to transceiver communications; however, the console transmissions are not overidden. In the event that both override capabilities are activated, the control center and the PTS control trailer will have two-way communications, but only the control center transmissions will be heard by other Type 1 transceivers. If a transceiver Is transmitting when the override Is activated, it can continue to transmit until the 30 second timer times out, but will not be able to key up again after that with the override actuated.

RTMN HEADSETS FOR EMERGENCY BREATHING APPARATUS.
There are (4) SK0034-0600009 RTMN headsets on complex for transceiver use with the BioPak 45 or M26A-1 Canister Mask.

VOICE SIGNALLING SYSTEM.
This system is used to announce emergency conditions and to direct remedial action. It simultaneously addresses all persons in the launch complex and operates as a public address system. The VSS equipment bay contains a monitor speaker and volume unit meter panel, patch panel, power supply, power control panel, switch panel, two preamplifier and three audio power amplifier units. One preamplifier and two audio amplifiers operate at all times. One audio amplifier is for above ground speakers and one for below ground speakers. The second preamplifier is a spare and may be switched in to back up the operating preamplifier in case of failure. The third audio amplifier is a spare and may replace the exterior or interior amplifier. Above ground voice projectors have high power handling capability while the projectors used in the enclosed areas are generally of the low power type. Projector housings depend on expected use and environment. Housings are weather-proof, explosion-proof, standard, or combinations thereof. The power output is 5 to 50 watts, depending on use.

TELEVISION SURVEILLANCE SYSTEM.
This system consists of a television camera installed in the access Portal and a television monitor located on level 2 of the control center. The equipment provides security surveillance of personnel entering and leaving the launch complex. The camera and lens controls are preset during installation and are automatically controlled, and therefore do not require normal operating procedures. The composite video output signal is connected via closed-circuit coaxial cable to the monitor for display and observation by personnel within the control center. Missile combat crew personnel should attempt only minor picture adjustment and fuse replacement for CCTV camera and monitor.

PROBLEM ANALYSIS.
Intra-complex communications malfunctions are indicated by the COMM EQUIP ALARM indicator on the LCCFC and ALOC communications panel. The specific area of malfunction can be determined from the indications in the power equipment bays on level 3 of the control center. To determine the failed component and the effect on communications capability, refer to T. 0. 21M-LGM25C-2-18 (T.O. 21M-LGM25C-2-17 at VAFB).

INTER-COMPLEX COMMUNICATIONS SYSTEM.
The inter-complex communications system provides communication between launch complexes, the WCP, ACPs, and the support base. The inter-complex communications system consists of direct lines, dial lines, and inter-complex radio communications system.

DIRECT LINES.
ACPs and all standard launch complexes have a direct soft-wire line to the WCP. The direct line is used for communication between the WCP and the standard launch complexes and ACPs. The WCP has the capability of conferencing one entire squadron at a time on the direct wire line. The WCP operator has the capability of patching central security control (CSC) into this circuit. CSC, through their switchboard subscriber lines, may enter this circuit and confer with the WCP and launch complex or a squadron simultaneously.

DIAL LINES.
Dial lines facilitate communication between the launch complex and base offices, with extensions to the nation-wide telephone system through the central facilities switching operator. The dial lines are primarily used for administrative communications. Station locations are the LCCFC, ALOC, and pad chief's desk. The telephone instruments are standard commercial instruments, wall and console mounted, and equipped with both dials and ringers. The lines entering the complex are routed through the wire protection and distribution cabinet to provide connection and overload protection.

INTER-COMPLEX RADIO COMMUNICATIONS SYSTEM.
This system provides adequate inter-complex voice and data communication with maximum survivability. It is basically a three-channel system, providing transmission on three modulation channels: 0 to 4 kc for 465L signals and hard voice party line signals; 4 to 8 kc for hard voice and selective signalling systems; and 8 to 12 kc for PAS signals. The system employs uhf and vhf transmitting and receiving equipment for communicating between the WCP and all launch complexes. The system uses four vhf and four uhf frequencies at DMAFB, and three vhf and three uhf frequencies at MCAFB and LRAFB. Voice data is transmitted and received using hi-frequency antennas, 1-kilowatt transmitters, wideband and narrowband receivers, multiplex equipment, and data adapters.

At LRAFB and MCAFB, the WCP utilizes two uhf transmitters (one operating and one standby) to transmit hard voice, 465L, and PAS data to the launch complexes. The ACPs utilize a frequency diversity system (one vhf and one uhf transmitter operating) to transmit hard voice, 465L, and PAS data to the launch complexes. At LRAFB, the ACPs use a working/standby uhf system to transmit hard voice, 465L, and PAS data to the launch complexes (including repeaters). The repeaters automatically retransmit this information using a working/standby vhf system to all launch complexes. At DMAFB, all WCP and ACP transmissions are relayed by the Mt. Lemmon repeater station or by on-site repeater equipment. The hard voice circuits enable the WCP or ACP to communicate with each complex individually or an entire squadron in conference. The individual complexes have the capability of contacting the WCP, either ACP, or the other complexes (all-complex radio) at one time. The ACP is able to monitor on all-complex radio but cannot reply on that frequency. Each standard launch complex has two vhf transmitters (one operating and one standby). The standby transmitter will automatically switch to the operate mode upon failure of the primary transmitter. Hard voice party line is the designation given to the vhf system used by the standard launch complex. Since all basic complexes have the capability of transmitting and receiving on the same frequency, their communication is much the same as a telephone party line.

The inter-complex radio communication system automatic switching equipment, located in the wiring control and transmission equipment bay No. 3 on level 3 of the control center, does not require manual adjustment of the controls normally expected with radio communication equipment. This equipment determines applicability of selective signalling tones for a particular complex, and in conjunction with decoders of the terminal equipment cabinet on level 3 of the control center, lights a flashing indicator and provides a ringing tone at the LCCFC and ALOC. Oscillators of the terminal equipment cabinet provide the output signalling to notify other complexes of a radio call. The RADIO TONE CUT-OFF pushbutton-indicator on the LCCFC and ALOC communications panel is used to manually turn off selective signalling oscillators should the automatic system fail.

The multiplex-receiver group and the terminal equipment group are the primary support equipment for the inter-complex radio communication system. The multiplex- receiver group consists of receivers, oscillators, modulators, demodulators, and equipment status panel, and (DMAFB) a signal transfer panel. The terminal equipment group consists of data encoders and decoders required to process 465L data and clock signals, receiver monitors to monitor for excess noise level, and selective signalling oscillators and decoders. An 8-kc oscillator in the multiplex-receiver group is used in the process of changing the multiplexed 4- to 8-kc hard voice signal back into the original 0- to 4-kc voice transmission. The same oscillator supplies the 8- to 12-kc demodulators, which accomplish the same function for PAS signals. There are three S-kc oscillators, one operating and two on standby.

Each unit of the multiplex-receiver group and terminal equipment group has a fault sensing circuit. A 3825-cps tone is transmitted at all times by all operating transmitters at the WCP and ACPs. If the tone is not received by any complex, the appropriate demodulators will sense a fault. If the fault sensing circuitry of a module without a backup or parallel module detects a fault, only the outage indicator will light on the fault indicator panels. The normal indicator will remain lighted on the fault indicator panel on the multiplexer rack. If a fault is detected in the operating unit of an operating/ standby pair, a fault indicator will light on the defective unit and remote fault indicators will light on the fault indicator panel on the ALOC and multiplex-receiver group. Also, the output of the operating unit is disconnected and the spare unit is turned on. If the spare unit fails, an outage indicator will light on the two fault panels. A fault in the working module causes the following sequence of events: At DMAFB only. There are two SACCS DATA SELECT switches (ACP-1 and ACP-2) located on a front panel (A83) of the terminal equipment group at all standard BLXs and Repeaters. Their function is to select a direct or repeated SACCS (465L) receive path from the ACPs in case the receive path being used deteriorates. These switches are also used to manually slave the SACCS test message to the direct and repeated paths during maintenance procedures.
 * Fault indicator (amber) on failed unit lights.
 * Appropriate fault indicator on multiplex-receiver status indicator panel lights and associated normal indicator goes out.
 * Appropriate fault indicator on ALOC fault indicator panel lights.
 * Power is applied to standby unit.
 * Output of failed unit is disconnected from system and output of standby unit is connected to system.

PROBLEM ANALYSIS.
A malfunction in the inter-complex radio communication system equipment is reflected on the ALOC fault indicator panel. This panel indicates the area of malfunction and its effect on the operating/ standby components within that area. Observation of the fault indications on the multiplexer-receiver group and terminal equipment cabinet will indicate the specific component which has malfunctioned. T. 0. 21MLGM25C-2-24 contains information necessary to determine component functions and system capabilities. The COMM EQUIP ALARM indicator on the ALOC and LCCFC communications panel lights red on certain inter-complex radio communication system malfunctions such as transmission equipment bay No. 1 (LCCFC communications wiring), hay No. 2 (ALOC communications wiring), and hay No. 3 (automatic switching equipment wiring). If the COMM EQUIP ALARM indicator lights red, fault indications in the power equipment hays will indicate the specific area of malfunction. T. 0. 21M-LGM25C-2-18 (T. 0. 21MLGM25C-2-17 at VAFB) contains information necessary to determine component functions and system capabilities. A detailed analysis of the performance of the Inter-complex Radio Communication System equipment may he performed with the IRCS Test Panel Assembly, which is mounted on the PAS cabinet in the ALOC or the ASCC console. This panel is equipped with controls, switches, and indicators that may be used for monitoring specific functions of the equipment during system operation, or for isolating malfunctions to a particular equipment area. This panel will normally he operated under the direction of acommunications specialist. See figures 1-42 and 1-43 for a description of the IRCS Test Panel Assembly.

EXTERNAL COMMUNICATIONS SYSTEMS.
The external communications systems are used for receiving and transmitting command instructions for SAC headquarters, airborne command post, numbered Air Force headquarters, and the WCP or ACPs. They consist of 465L equipment, 487L SLFC system, the PAS, hf (single side band) radio (HF SSB), and uhf radio.

465L COMMUNICATIONS EQUIPMENT.
(See figure 1-44.) This equipment is part of a large scale digital data communications and command system. The ACP has the caoahilitv of inserting messages into the system via the input keyboard and of screening messages from the system on the Line Printer Unit. These messages are automatically encrypted and then modulated for transmission on telephone lines. The link from the ACP is to SAC or one of the three numbered Air Force headquarters. At the headquarters, the message is automatically examined for parity, formal errors logged on magnetic tape, and routed to the message addresses (which can be any WCP, ACP, or headquarters printer station in the system). The equipment at standard launch complexes receives "klaxon" and "alert" type messages only, not having the capability of transmission. The "klaxon" and "alert" messages can only be generated by SAC headquarters or a numbered Air Force headquarters. When received at the WCP and ACPs, they are transmitted to the standard launch complexes via radio links without being electronically encrypted. The equipment at the standard launch complexes accepts the first message received from these sources, lighting the KLAXON and ALERT indicators and printing the message. Two cabinets of equipment at the ACP are associated only with "klaxon" and "alert" messages. One provides the same indications as in the standard launch complexes and, in addition, has the capability of initiating an "alert acknowledge" message back to the originator when the ALERT ACKNOWLEDGE pushbutton is depressed. The other cabinet is associated with the distribution of the "klaxon" and 'alert" messages to the standard launch complexes and the other ACP. Refer to Section III for daily checkout procedures.

487L COMMUNICATIONS EQUIPMENT.
The 487L Survivable Low Frequency Communications System (SLFCS), as incorporated in Titan II Weapon System, provides a reliable and survivable communication system for Command Control Communications between remotely located Strategic Air Command (SAC) Command Post transmit /receive sites and Titan II Missile Wing Command Posts (MWCP), Alternate Command Posts (ACP) and Launch Control Centers (LCC). The Titan II sites have only receiving capabilities. The signals are transmitted from remote SAC transmit /receive (T/R) facilities. These sites can also receive from an airborne command post. The receivers can cover a frequency range between 14 and 60 KHz in 10 Hz steps. The normal message reception is teletype and is reproduced by a miniature page printer.

PRIMARY ALERTING SYSTEM.
This system is used to provide primary alerting and strike information from SAC and numbered AIR FORCE headquarters to all launch complexes. A direct wire connection exists between SAC headquarters, number Air Force headquarters, the WCP, and the ACPs. The connection to the ACt's from number Air Force headquarters is hardened for a distance of 4.7 nautical miles from the ACP's. The PAS command is retransmitted from the WCP and the ACP's (ACP-1 only at t*(AFB) to the launch complexes via the inter-complex radio communication system in the 8-12 KHz portion of the baseband-modulation frequency. PAS messages from SAC are transmitted via the WCP, and messages from numbered Air Forces via the ACP connection. PAS voice messages are broadcast over speakers mounted on the LCCFC and to the left of the ALOC. transmitter-receiver not to be operated below 3 MHz. Refer to Section III for operating procedures.

UHF RADIO.
This system provides ground-to-air communications, and is used by SAC and numbered Air Force headquarters as a backup means of communications. The system operates in the 225.0 MHz to 399.975 MHz range. The system may be remotely operated from the ALOC on any one of 19 preset frequencies. The receiver-transmitter unit is located in the HF-SSB/UHF equipment rack on level 2 of the control center. The transmitter has a power output capability of 100 watts. Refer to Section III for operating procedures.

PROBLEM ANALYSIS.
Analysis is limited to the minor adjustments specified in Section III.

ANTENNA SYSTEMS
The antenna systems provide the means of receiving and transmitting the necessary frequencies for the individual radio systems. Some antennas have hardened backups that can be erected in the event the primary antenna is destroyed r damaged. Antenna systems are the RTMN antenna, the inter-complex radio :oumiunication system antenna (one or two soft operating and two hard backup), the F discage antenna, the HF hard antenna (two at ACP), and the UHF hard antenna.

RADIO-TYPE MAINTENANCE NETWORK ANTENNAS.
The antenna system used with the RTMN consists of two coaxial cable branches. The above-ground antenna cable branch connects the base station radio in the control center to the coaxial slotted cable antenna in the access portal and to an above-ground folded monopole antenna on the VSS pole at the access portal. The branch incorporates a switch, remotely controlled from the LCCFC and ALOC for enabling the above-ground antenna or disabling the above-ground antenna when not in use. The antenna system is designed to provide reliable above-ground communication. A variable attenuator is connected to the above-ground antenna coax to limit above-ground RTMN radiation to a minimum of 2,000 feet without interfering with RTMN transmissions at other launch complexes. The below-ground antenna branch is a continuous coaxial slotted cable which is routed from the base station radio equipment bay in the control center throughout the under-ground launch complex.

INTER-COMPLEX RADIO COMMUNICATION SYSTEM ANTENNAS.
These antennas are designed to transmit and receive uhf and vhf with a high degree of reliability. To attain the degree of reliability and minimize frequency loss due to terrain, distance, and interference, space diversity type antennas are required at certain launch complexes to receive from the WCP. All launch complexes are equipped with a single, soft, frequency-diversity antenna. Each soft, frequency-diversity antenna at a launch complex is backed up by two identical hard antennas. If a hard antenna is selected for automatic switchover and a soft antenna has been tilted 12.5(2±2.5) degrees from the vertical, a switching action would erect the selected hard antenna. The hard antenna becomes operational within 50 seconds from the time power is applied to activate the erection system. A pneumatic power system is provided to actuate the hard antenna door lock and raise the antenna to its maximum height. The antenna door system secures and protects the antenna erecting-support mechanism until the antenna door is raised to a 90 degree angle with respect to ground level. The bard antenna system is designed to withstand severe nuclear blast effect while below-ground. The soft bi-frequency antenna utilized for reception and transmission at the WCP does not have hard antenna backup capability. Launch complexes using space-diversity equipment do not have space-diversity antenna backup capability.

HF DISCAGE ANTENNA.
The hf discage antenna is a fixed, omnidirectional antenna. It combines an elevated discone and a folded-cage monopole to cover the frequency range from 3 to 30 MHz. The folded-cage monopole portion covers the 3- to 6 MHz range, and the discone portion covers the 6- to 30-MHz range. The correct portion of the antenna to use within each frequency range may be selected from the HF-SSB/UHF equipment rack.

HF HARD ANTENNA.
The hf hard antenna is designed to replace the hf discage antenna in the event the discage antenna should fail. It is designed to operate within the frequency range between 2 and 30 MHz. Standard launch complexes have one antenna and the ACPs have two antennas. Actuation of the antenna control by the operator at the ALOC initiates the opening of the antenna silo door and starts two 3-phase ac induction motors mounted on the antenna. Each motor drives a four-wheel friction drive assembly. The telescoped antenna mast sections are gripped between the two friction drive assemblies. The drive wheels extend or retract the antenna mast sections as demanded by the antenna control operator. The mast sections are automatically locked together as they are extended through the open antenna silo door. A height sensing circuit determines antenna mast height for a selected transmitting frequency (this height varies from 7.4 feet at 30 MHz to 117 feet at 2 MHz. When the desired height is reached, the antenna drive motors are stopped and locked. The antenna is positioned to operate with a voltage standing wave ratio (VSWR) of 2 to 1 or less at the transmitting frequency selected. Refer to Section III for Operating procedures. An electrical interference filter group cabinet OA-8501/F or OA-8512/F is located in the antenna silo to protect electrical equipment from over voltage surges.

UHF HARD ANTENNA.
The uhf hard antenna is a fixed installation providing basic uhf communications. The antenna monopole radiator is a solid cylindrical probe weighing about 200 pounds, insulated from a heavy antenna base weighing 1700 pounds. The probe is weather protected by a sealed, glass-reinforced, laminated plastic shield. The heavy structure and streamlined surface configuration provide resistance to extreme weather and temperature environments. The radiation pattern is omnidirectional in the horizontal plane and moderately directional in the vertical plane. The antenna can operate within a frequency range of 225 to 400 MHz and has a maximum power handling capacity of 100 watts. The antenna rises a total of 21. 5 inches above ground.

ON-SITE REPEATERS (LRAFB).
On-site repeaters are used for radio retransmission of ACPs. Repeater operation is automatic at both sites 3 73-2 and 374-8).

POWER DISTRIBUTION.
Primary power for system operation is 120 vac, 60 cps. The power arrives at MCC-1 via commercial or standby power and is transmitted to MCC-2 on level 3 of the control center via the MCC-2 feeder breaker on MCC-1. At this point the power is 480 vac. MCC-2 supplies the 480 vac to transformer TR-7 through a 50-ampere circuit breaker. Transformer TR-7 reduces the 480 vac to 120/208 vac and supplies communication system branch circuit panels CC-3. CC-3 supplies 120/208 vac to the hf radio, inter-complex ,radio communication system transmitters and 15 and 24 vdc power supplies, the PAS, the VSS bay, the RTMN radio hay, the uhf radio, the 465L equipment, the 487L SLFC system, and the power equipment bay. Refer to SAC CEM 21-SM68B-2--21 for circuit breaker schedules. MCC-2 has a separate circuit to power the hf hard antenna electric motors and also routes power through CC-2A to power the television monitor. Input power for the inter-complex radio communication receiving system is routed from CC-3 to the multiplex-receiver group and the terminal equipment group, and the line ac voltage is applied to the 15 and 24 vdc power supplies. Two 24 vdc power supplies convert the ac line voltage to 24 vdc, which provides power for operating the control circuitry, panel fault lamps, unit modules, lamp switches, and transfer relays within the equipment shelves of the multiplex-receiver group, terminal equipment group, and antenna control group. During normal operation, the two 24 vdc power supplies are operated in parallel and share the load equally, If either power supply fails, the other carries the load. If both fail, an alternate power source lights the COMMON EQUIP FAULT indicator and TRANSMIT OUTAGE indicator on the ALOC fault indicator panel. Eight 15 vdc power supplies provide 15- and 30-vdc power to operate the modules in the equipment shelves of the multiplexer-receiver group and the terminal equipment group. Three 15 vdc power supplies are located in the terminal equipment group, and five 15 vdc power supplies are located in the multiplex-receiver group which convert ac line voltage to 15 vdc. To produce 30 vdc, two power supplies are connected in series. A power supply control module, located in the multiplex-receiver, connects an alternate power supply when the 30 vdc combination of the operating power supplies faults. Input power to the intra-complex communication system is routed through CC-3 to the two 24 vdc battery chargers in the 24 vdc power equipment bay. The battery chargers convert the ac line voltage and provide 24 vdc for: DC interrupter and ringing machine and four 6 volt batteries connected in series within the power equipment bay, WCT-1, WCT-2, WCT-3, VSS, RAD-1, LCCFC and ALOC communication panels, and transistor amplifiers behind the PAS speakers. During normal operation Charger #1 delivers the charging current up to its limit at which point Charger #2 comes on and delivers the additional required charging current.

At LRAFB, selected complexes have an additional 26 vdc power supply. This power supply receives 120 vac from CC-3 and converts it to 26 vdc for the 35002A pre-amplifier. The power supply and pre-amplifier are located in the Terminal Equipment Group at both ACPs. At the selected BLXs (373-4, 373-6, 373-7, 374-2, 374-3, 374-4, 374-6, and 374-7) the power supply and pre-amplifier are located in the Multiplex-Receiver Group.

In the event both commercial and standby power should fail, the following systems will be inoperative: inter-complex radio communication system, all external communications systems, VSS, and television monitor. Although SLFCS receiver capability is disabled, backup DC power is provided to the sequential timer which provides DC power to the demodulator real time circuits to maintain real time and to the KG-38 to maintain key code and key run up. Real time will be maintained for 6 hours if the KG-38 is turned off within 15 minutes after a loss of AC power. The power equipment bay contains four 6 vdc batteries which could supply 24 vdc for 12 hours to the WTMN, inter-complex and intra-complex direct lines, and dial lines. The radio bay has self-contained batteries which would allow the RTMN to operate for a minimum of 8 hours. A momentary loss of AC power may cause the inter-complex communications system SOFT ANTENNA CONNECTED indicator to go out and/or loss of system communication. Loss of UHF power will also occur. These are not equipment malfunctions and may be remedied by pressing the MAN SOFT ANTENNA SELECTION pushbutton and momentarily setting the UHF POWER switch to ON.

COMMUNICATIONS PROCEDURES
Standard communication procedures are essential for safe and reliable launch complex operations. Communications within the launch complex shall normally be by voice signalling system, direct line telephone, RTMN, or WTMN. Communications to stations not within the launch complex shall be by direct line, dial line, HF SSB/UHF radio, or inter-complex radio communications system.

The F5 ON MR lamp will illuminate white when any F5 transmitter is on the air and will extinguish when a BLX has completed its portion of the radio conversation. Because this F5 ON AIR lamp will not he an indication of the period during which acommand post is talking back to the BLX, a time delay (adjustable from 4 to 8 seconds) allows the F5 ON AIR lamp to remain lighted after the F5 transmitter has been unkeyed. This 4- to 8-second period is intended to allow for the average command post talk-back time to the BLX. Therefore, prior to accessing the communications console at a BLX to make an 11ICS radio call, the console operator should observe whether or not the F5 ON AIR lamp is lighted white and should wait until the lamp is extinguished before the radio call is made.

COMMUNICATIONS DISCIPLINE
Clear and precise language and slightly slower, well-modulated speech shall Be used in all inter-phone and radio communications. Proper communications identifiers, commands, reports and action responses shall be used during all launch complex operations. Communications will be limited to those pertinent to launch complex operations and maintenance on all circuits except the dial phones. The proper procedure for testing the operation of headsets is to announce: "testing 1, 2, 3, testing out." Avoid blowing in the microphone.

Personnel may be assigned call sign identifiers or addressed by rank and last name. Area identifiers may also be used for initial contact calls. The word "Roger" shall be used when acknowledging understanding of instructions or commands. Initiation and termination of intra-complex communcations on the maintenance networks shall follow these general rules a* Calls on an activated line: State communications identifier of persons or stations being addressed, state your communications identifier and location, and give brief reason for call. For example, "Commander, propellant team supervisor at position for fuel transfer."
 * VSS system calls: State communications identifier of persons or locations being called and state action to be taken or information to be discussed. For example, "Pad Chief, call commander on wire maintenance net."
 * Answering an intra-net call or VSS signal by WTMN or HTMN: State your communications identifier and location. For example, "Pad Chief level 2."
 * Terminating intra-net communications: State your communications identifier and the fact that you are releasing the net. For example, "Pad Chief releasing net."

Most intra-net communications consist of commands, responses to action commands, and reporting of conditions or indications. Commands may be for equipment activation or for a report of conditions or indications. In performance of MCC procedures and checklists, commands, responses, and announcements will be made as indicated in appropriate checklists, and will he announced in a manner that all personnel are able to hear and understand. During periods of critical maintenance, e. g., PTS operations, end-to-end phasing, etc., where the person reading the checklist or procedure is not in a position to observe the action directed by the checklist or procedure, communications discipline must be strictly enforced by the MCC. The person reading the checklist or procedure will give the command and response. The person to perform the action will repeat the required action and then pause to allow for correction if required. He will then perform the action directed and repeat the command and response. For example: PTS team chief: "Valve V-68, . .....Closed." Technician "Close Valve V-68." Pause, completes action, Technician:"Valve V-68 closed."

LGM-25C MISSILE
The LGM-25C ballistic missile consists of a two-stage, rocket engine powered vehicle and an RV. Provisions are included for in-flight separation of Stage II from Stage I, and separation of the RV from Stage II. The Stage I and Stage II vehicles each contain propellant and pressurization, rocket engine, hydraulic, and electrical systems, and explosive components. In addition, Stage II contains the flight control system and missile guidance set. Figure 1-51 illustrates the major sections of the LGM-25C missile.

AIRFRAME
The airframe (figure 1-52) is a two-stage, aerodynamically stable structure that houses and protects the airborne missile equipment during powered flight. The missile guidance set enables the shutdown and staging enable relay to initiate Stage I separation. The missile guidance set initiates Stage II and RV separation. Each stage is 10 feet in diameter and has fuel and oxidizer tanks in tandem, with the walls of the tanks forming the skin of the missile in those areas. External conduits are attached to the outside surfaces of the tanks to provide passage for wire bundles and tubing. Access doors are provided on the missile forward, aft, and between-tanks structures for inspection and maintenance. A manhole cover for tank entry is located on the forward dome of each tank.

The Stage I airframe consists of an interstage structure, oxidizer tank forward skirt, oxidizer tank, between-tanks structure, and fuel tank. The interstage structure, oxidizer tank forward skirt, and between-tanks structure are all fabricated assemblies utilizing riveted skin, stringers, and frame. The oxidizer tank is a welded structure consisting of a forward dome, tank barrel, an aft dome, and a feedline. The fuel tank, also a welded structure, consists of a forward dome, tank barrel, an aft cone, and internal conduit.

Stage II airframe consists of a transition section, oxidizer tank, between-tanks structure, fuel tank, and aft skirt. The transition assembly, between-tanks structure, and aft skirt are all fabricated assemblies utilizing riveted skin, stringers, and frames. The oxidizer tank and fuel tank are welded structures consisting of forward and aft domes.

ROCKET ENGINE SYSTEM
The missile rocket engine system consists of a Stage I rocket engine (LB-87-AJ--5) and a Stage II rocket engine (LR-91-AJ-5). The Stage I rocket engine is designed to operate with a rated thrust of 430,000 pounds at sea level; Stage II rocket engine is designed to operate with a rated thrust of 100, 000 pounds at an altitude of 250, 000 feet. An autogenous propellant tank pressurization system (paragraph 1-223) is part of the rocket engine system.

The Stage I rocket engine (figure -53) consists of two independent subassemblies mounted on a single engine frame. Each subassembly contains a thrust chamber assembly, a turbopump assembly, a gas generator, and an engine start system. The two subassemblies have an integrated electrical system for simultaneous operation.

Stage I rocket engine operation is initiated by the launch-command signal from the LCCFC. Prior to Stage I rocket engine operation, the missile prevalves are opened to allow propellant to flow through the suction lines to the rocket engine. At countdown T--zero, a 28 vdc signal is applied to the two solid-propellant starter cartridge initiators. Ignition and burning of the gas pressure generator produces hot gases which are directed through an inlet nozzle to the turbopump assembly turbine for initial acceleration and running of the turbine. The turbine, through a gear train, drives the fuel and oxidizer pumps. The fuel and oxidizer pumps deliver propellants through discharge lines to the thrust chamber valves. When fuel discharge pressure within the fuel discharge lines reaches 310 psi, a pressure actuated valve (thrust chamber valve pressure sequencing valve) opens. Through mechanical coupling, the thrust chamber fuel and oxidizer valves open, fuel flows down the thrust chamber coolant tubes, back up into the injector, and is emitted into the combustion chamber. Oxidizer flow is directly through the injector into the combustion chamber. The propellants ignite hypergolically and the flow of expanding gases from the nozzle produces thrust. Rocket engine sustained operation is dependent upon bootstrap operation involving the turbo- pump assembly and the gas generator. Simultaneously with the flow of propellants to the thrust chamber, a small amount of fuel and oxidizer is drawn off below the thrust chamber valves into gas generator fuel and oxidizer lines. Cavitating venturis, located in the gas generator lines, control propellant flow to the gas generator. Propellant pressures open the check valves installed in the lines, allowing propellant to enter the gas generator. The propellants ignite hypergolically and a fuel-rich gas is produced which enters the turbine inlet, drives the turbine, and thereby sustains turbopump assembly operation. An autogenous pressurization system is used for inflight propellant tank pressurization. The system utilizes a small portion of cooled exhaust gas to pressurize the fuel tank.

The oxidizer tank is pressurized by directing a small amount of oxidizer into an autogenous system super-heater where the oxidizer is heated and converted to a gas. The expanding gas is directed to the oxidizer tank for !nflight tank pressurization. Engine shutdown, at the end of Stage I flight, occurs when either oxidizer or fuel is depleted, causing a subsequent drop in thrust chamber pressure which is detected by the thrust chamber pressure switch. When this lower pressure is sensed, a signal is sent to the thrust chamber pressure sequencing valve to initiate closing of the thrust chamber valves, thereby terminating rocket engine operation. Simultaneously a signal is sent to the Stage II separation nut squibs and gas pressure generator to initiate Stage IT separation and rocket engine start.

The Stage II rocket engine (figure 1-54) consists of a thrust chamber assembly with ablative skirt, turbopump assembly, gas generator, fuel tank autogenous pressurization system, roll control assembly, and engine control system.

Except for minor differences, the Stage II rocket engine operates the same as the Stage I rocket engine. The initial start signal for the Stage IT rocket engine is transmitted from the thrust chamber pressure switches located on the Stage I rocket engine. At Stage I engine shutdown, a signal is transmitted from the Stage I pressure switches to initiate the Stage II solid propellant starter cartridge and separation nut squibs. The rocket engine self-sustaining and shutdown operations are similar to those of Stage I; however, the shutdown signal for Stage II is initiated by the missile guidance set. A roll control nozzle, utilizing exhaust gas from the gas generator, is incorporated in the system to provide roll control of the missile during Stage II operation. The roll control nozzle is connected to a hydraulic actuator installed between the missile and the roll control assembly. The flight control system receives guidance signals from the missile guidance set and sends control signals to the actuator. Pressurization of the Stage II oxidizer tank is not required in flght.. The Stage II fuel tank is pressurized by utilizing cooled exhaust gas.

AIRBORNE PROPELLANT SYSTEM
The airborne propellant system (figure 1-55) consists of fuel and oxidizer tanks, disconnects, pressure transducers, storage valves, and pressurization and vent piping. 1-219. The Stage I fuel and oxidizer fill-drain and storage valve No. 2 drain disconnects are located in the Stage I engine compartment. The remaining Stage I and Stage IT disconnects are located at various points on the outer skin of the missile. The disconnect ground halves are connected to these disconnects to direct the flow of propellants and gases to and from the missile tanks. The disconnects are self-sealing and must be manually connected and disconnected.

Pressure transducers are located in the dome of each missile propellant tank. The output of these transducers is connected to a digital meter mounted on the LCCFC indicating the selected propellant tank pressure in pounds per square inch gauge (PSIG). The transducer output is also used to operate related propellant system equipment if structural pressure limits are exceeded during loading or unloading operations. This function is accomplished by conversion of the transducer output to a 28 vdc control signal in the PTS structural pressure control unit.

There are six storage valves: four in the Stage I engine compartment and two in the Stage II engine compartment. These valves are gas pressure (squib) actuated, butterfly valves with zero-leak diaphragms. The diaphragms prevent propellants stored in the missile tanks from entering the engines. Each valve has a positive locking device that automatically locks the valve in the open position when the valve is actuated. Fill-drain disconnects are directly connected to one fuel valve and one oxidizer valve in Stage L Two other Stage I valves have disconnects which are used to drain propellants trapped above the valves during unloading operations. Fill-drain disconnects are connected to Stage II valves by flex hoses.

The pressurization and vent piping for the Stage I fuel and oxidizer tanks and the Stage If	tank consists of flex hose between the top of each tank and disconnects on the skin of the missile. The Stage II tank pressurization and vent piping is a flex hose between the bottom of the tank and a disconnect on the missile skin. These systems are used to safely vent gases away from the missile during loading operations and pressurize the missile tanks to flight pressure after loading. They are also used to pressurize the missile for leak check, purging, blanketing, and propellant unloading. 1-

AUTOGENOUS PRESSURIZATION SYSTEM
Autogenous pressurization systems (figure 1-56) are used for the inflight propellant tank pressurization of both stages of the LGM-25C missile. Stage II incorporates a fuel tank autogenous pressurization system only. Immediately after propellant loading of the missile, the Stage II oxidizer tank is pressurized with nitrogen and sealed. No additional inflight pressurization is required. The Stage I autogenous pressurization system consists of a fuel tank pressurization system and an oxidizer tank pressurization system. After loading, the Stage I fuel and oxidizer tanks and the Stage II fuel tank are pressurized and sealed. The fuel tank pressurization system consists of a gas cooler, hot gas bypass orifice, flow control orifice, sonic nozzle, burst diaphragm, and connecting tubing. The oxidizer tank pressurization system consists of a superheater, oxidizer bypass orifice, eavitating venturi and filter, flow control orifice, burst diaphragm, and connecting tubing.

FUEL TANK PRESSURIZATION SYSTEMS.
The fuel tank autogenous pressurization systems used on both stages of the LGM-25C missile are identical. Both systems cool the hot exhaust gas from the gas generator from +1600 degrees F to +200 degrees F in the gas cooler. The cooled exhaust gas is used to maintain the required fuel tank pressure of 24 to 29 psia on Stage I and 49 to 54 psia on Stage II. Gas enthalpy control is provided by installing orifices of proper size in the bypass lines of the gas cooler. The amount of gas fed to the fuel tank is regulated by the use of a sonic flow control nozzle installed in the line between the gas cooler and the fuel tank. When pressure within the system reaches approximately 300 psig, the burst diaphragm, installed upstream of the gas cooler, ruptures allowing flow of cooled exhaust gases to the missile fuel tank.

AIRBORNE HYDRAULIC SYSTEM
The airborne hydraulic system (figure 1-57) supplies pressure to gimbal the thrust chambers of the rocket engines, roll control nozzle, and vernier rocket motors. Each stage has a closed-loop system consisting of hydraulic pumps, accumulators, hydraulic filters, actuators and associated plumbing to produce the required hydraulic pressure. Each stage has a separate, electric motor driven pump to supply hydraulic power when the rocket engines are not firing.

The Stage I hydraulic system provides hydraulic pressure to the Stage I servo actuators. Prior to flight, the Stage I hydraulic system is powered by an electric motor driven pump which receives ground electric power through an umbilical connector. During flight, this system is powered by a pump that is driven by a turbine pump assembly on the Stage I engine. Hydraulic pressure generated by the Stage I pump is used by the servo actuators to gimbal the thrust chamber during Stage I flight.

The Stage II hydraulic system provides hydraulic pressure to the Stage II engine, roll control, and vernier actuators. During sustainer engine firing, the hydraulic system is powered by the turbine pump assembly driven pump. At sustainer engine shutdown the electric motor driven pump starts and supplies hydraulic power to the vernier rocket motor actuators. The electric motor receives power from the vernier hydraulic power supply (VHPS) battery which is located in the Stage II equipment compartment. The battery power switch is closed by a signal from the Stage II sustainer engine shutdown relay during flight.

AIRBORNE ELECTRICAL SYSTEM
The airborne electrical system (figure 1-58) is composed of the accessory power supply (APS) battery, the VHPS battery, motor-driven switches, relays, hydraulic pump motors, wire distribution, connectors, disconnects, and distribution buses. Miscellaneous electrical equipment includes such items as umbilical connectors, diodes, resistors, timers terminal boards, and wiring. The electrical system is monitored and verified for operational readiness before launch by the LCS.

During a controlled flight, electrical power is supplied by the APS battery and the VHPS battery which are located in the guidance bay of Stage II. The APS battery is activated by the LCS during launch countdown and supplies 28 vdc power to missile equipment during launch and flight. The VHPS battery is also activated by the LCS during launch countdown and supplies 28 vdc power to Stage II hydraulic pump motor, relays, and motor- driven switches. Power from the VHPS battery is routed through the VI]PS power switch which is closed by a signal from the Stage II engine shutdown control relay. Figure 1-59 displays sequence of basic functions of the missile electrical system during launch countdown and flight.

When power is transferred to the APS battery in a launch sequence or if a 28 VDC power transient occurs with the IGS in memory mode, the 28 VDC ABN MALFUNCTIONS indicator may light and malfunction code 44 and HALF CODE RESET displayed on the MGACG if the airborne comparator senses an out of tolerance condition. The 28 VDC indicator will automatically extinguish if the out of tolerance condition is no longer present, and malfunction code 44 and MALF CODE RESET will remain displayed until manually reset.

EXPLOSIVE COMPONENTS
Explosive components are devices used within the missile to produce thrust, supply ignition, permit missile staging, and activate components. Explosive components include gas pressure generators, vernier rocket motors, pitch rockets, igniters, and initiators. Gas pressure generators are used to open Stage I and Stage II propellant storage valves, release staging nuts and terminate vernier rocket thrust. Two solid propellant vernier rocket motors are mounted inside the Stage II engine compartment. The pitch rockets are two solid propellant rockets mounted in the between-tanks area of Stage II, equidistant from one another. Pitch rocket nozzles are protected by external fairings which are ejected by the rocket blast at ignition. Initiators are used to start the vernier rocket motors and activate engine gas pressure generators. Igniters are used to start pitch rockets. The APS and VUPS batteries are activated by squibs which are sealed inside the battery cases.

An ordnance safety switch (OSS) locks out all electrical signals to explosive components except signals to Stage I storage valve gas pressure generators. A signal from the LCS closes the OSS, activating the missile batteries and Stage II storage valve cartridges and closes the Stage I engine start switch, igniting Stage I engine gas pressure generators. Upon receiving a signal from the thrust chamber pressure switches, the launch control set ignites the hold-down nut cartridges to release the missile. During missile flight, explosive components receive initiation signals from the missile guidance computer. Figure 1-58 displays sequence of explosive component activation during launch countdown and missile flight.

Another explosive component on the missile is the Butterfly Valve Lock; however, unlike the other explosive components the explosive charges within the BVL have no function during a missile launch. The purpose of these charges is to prevent unauthorized entry into the BVL for the purpose of enabling an unauthorized launch, refer to Paragraph 1-113. Detailed information on explosive components is available in applicable technical orders for each system.

FLIGHT CONTROL SYSTEM
The flight control system (figure 1-59) consists of the Stage I rate gyro package, Stage II autopilot system, and servo actuators. The flight control system receives guidance steering signals from the missile guidance set and converts then into stabilized control commands which are transmitted to the appropriate servo actuator during missile powered flight. The Stage II autopilot system, located in the Stage II between-tanks area, contains circuitry necessary to receive pitci, roil, and yaw steering signals from the missile guidance set, mix these signals with signals from the rate gyros, and transmit the resulting signals to the appropriate servo actuators to control missile attitude about the pitch, roll and yaw axes. In addition, the autopilot system contains the Stage II rate gyros and an inverter for supplying power to the magnetic amplifier and rate gyros. The servo actuators convert autopilot control signals into mechanical movement for positioning of the Stage I and Stage II rocket engines, the roll control nozzle and the vernier rocket motors. Each actuator is a self-contained position servo, utilizing mechanical piston feedback to balance actuator position. During Stage I flight, the guidance signals are mixed with the Stage I and Stage II rate gyro signals and transmitted to the Stage I engine actuators. A gain-change-discrete signal is also sent from the missile guidance set to the flight control system. When a staging signal is received from a thrust chamber pressure switch, the Stage I rate gyro signals are disconnected from the autopilot circuitry. During Stage II flight, the guidance signals are mixed with the Stage II rate gyro signals and transmitted to the Stage II engine actuators. During vernier flight, the signal flow is identical to Stage II flight. Hydraulic power is supplied by the vernier hydraulic power supply electric motor pump. A qualitative end-to-end check of the flight control system is performed by the CMG during the launch sequence.

MISSILE GUIDANCE SET
The missile guidance set (figure 1-60) is located in the between-tanks section of Stage II and consists of the IMU and the MGC. The IMU is a sensing device which feeds information into the MGC. The MGC, in turn, uses this information to perform guidance and discrete functions.

The IMU is enclosed in a pressurized rigid aluminum structure designed to allow passive cooling by radiation and conduction. It consists of an inertial reference unit and inertial measurement unit electronics. The inertial reference unit utilizes a four-gimbal assembly to support a rotating platform which is stabilized at a reference attitude. It contains the gyros, accelerometers, motors, synchros, and resolvers for stabilizing the platform and producing signals proportional to changes in missile attitude and velocity. The inertial measurement unit electronics contains all the power supplies and electronics for the stabilization loops, accelerometer loops, gyro torquing, moding, fault isolation, and temperature control. The inertial measurement unit electronics is composed of printed circuit boards which are divided by function to simplify maintenance.

Three accelerometers and three stabilization gyros are mounted on the platform axis so their input axes are mutually perpendicular. The instrument axes are identified as x, y, and z. When the platform is erected, the z axis is vertical while the x and y axes are in the horizontal plane. The construction of the inner gimbal assures that the z instrument axis and inner gimbal axis remain parallel at all times. However, rotation of a portion of the inner gimbal about its axis varies the angular relationship of the x and y axes to the middle and outer axes of the inertial reference unit. The inner gimbal is mechanized as a two-part assembly, the z platform and the x-y platform. During operation, the z platform is prevented from rotation about the inner gimbal axis except for rotation due to earth rate and gyro drift. A synchronous motor, mounted on the z platform, drives the x-y platform about the inner gimbal axis at a constant rate of 114 revolution per minute with respect to the z platform. Platform rotation enables separation of inertial instrument error from external influences.

The MGC is housed in a pressurized rigid aluminum structure designed to allow for passive cooling by radiation and conduction. The MGC is a programmable, high speed, general purpose, parallel computer employing 19-bit instruction words and 24-bit data words. The processor provides 57 basic instructions and the computer has a memory of 16,384 words. Arithmetic operations are binary, with negative numbers in two's compliment. All logic functions are mechanized with small-scale and medium-scate integrated circuits. The MGC controls the alignment of the IMU via commands from the MGACC.

Target coefficients and IMU coefficients are loaded in the MGC memory through the punched tape reader in the MGACG. The target coefficients are based on particular launch complex and target location characteristics such as gravity variations. The INU coefficients are values which compensate for the varying characteristics of gyros and accelerometers within the unit. These coefficients, either established at the factory or obtained during the calibrate test, together with the attitude and velocity inputs from the unit enable the MGC to perform velocity-tobe-gained steering computations in the later portions of flight and to accomplish the roll and pitch programs during booster flight. The resulting steering commands are dc voltages. The direction and amount of corrective movement which the missile experiences as a result of these commands depend upon polarity and magnitude of the commands.

The MGC goes into a flight program as soon as the IGS has progressed to the inertial mode during a launch sequence. This is called time zero and is the base for all timed functions which are initiated during flight by the MGC. Actual lift-off occurs several seconds later. As the missile rises vertically during Stage I flight, the MGC issues steering signals which roll the missile until the missile is aligned in azimuth with the aim point. When azimuth alignment has been accomplished, the missile is pitched toward the aim point by steering signals from the NGC. Also during Stage I flight, the MGC issues two discrete signals. Like all other discrete signals issued during the flight program, these signals are issued only after the successful accomplishment of prior programmed events. The first signal is the control-system-gain-change-discrete signal which alters the gain of the engine actuator control circuitry. This gain change is necessary because the center of gravity changes as the propellant are consumed and because aerodynamic resistance decreases as altitude is gained. The second signal is a shutdown-and-staging-enable-discrete signal that energizes a shutdown and staging enable relay. When the relay is energized, it applies 28 vdc to the coil of the staging control relay. The staging control is not energized until a circuit ground is provided. When either of the Stage I engine thrust chamber pressures drops due to lack of propellant, a thrust chamber pressure switch closes and completes the staging control relay circuit by providing the ground. When energized, the staging control relay applies 28 vdc to the Stage I staging and shutdown switch which initiates Stage I engine shutdown, stage separation, and Stage II engine start.

Stage II engine operation begins immediately after booster shutdown. During the latter portion of Stage II flight and throughout the remainder of powered flight, the MGC performs velocity-to-be-gained steering computations. The MGC compares the actual position and velocity of the missile with the position and velocity which the missile would have in a previously calculated trajectory. On the basis of this comparison, the HOC issues pitch, yaw, and roll steering commands which alter the attitude of the missile and, in effect, change its velocity along the three mutually perpendicular computational axes. When the MGC issues a sustainer-engine-cutoff-discrete signal, Stage II flight is terminated and vernier flight is initiated. During this phase of flight, the HOC continues to make fine adjustments in missile velocity. Vernier flight is then terminated by a vernier-cutoff-discrete signal.

Vernier cutoff is the beginning of ballistic flight. From this point, the RV, after separation from Stage II, pursues a trajectory which will land it on target. Just before separation, the RV receives a pre-arm-discrete signal from the MGC which permits arming of the warhead at the proper time. This signal is followed by an RV release-discrete signal which separates the RV from Stage II. After separation, the RV falls free while the remaining Stage II section is sent into a different trajectory to further minimize detection of the RV. This is accomplished by firing pitch rockets. Firing of these rockets is accomplished by two computer- discrete signals, namely, ignite-pitch-rocket-No. 1 and ignite-pitchrocket-No. 2.

RE-ENTRY VEHICLE
(For classified information on the RV, refer to the 11N series Technical Orders.)

SAFETY
Personnel safety is maintained throughout the launch complex by hazard sensing and warning equipment, protective clothing and equipment, safety equipment, and safety requirements. Due to the hazardous conditions that could exist in the launch complex, personnel must be familiar with safety procedures and the use of safety equipment.

HAZARD SENSING AND WARNING EQUIPMENT
Hazard sensing and warning equipment is located throughout the launch complex for hazard sensing and warning of personnel; and controlling propellant vapor level, and fires. Hazard elimination, using water spray, air purge, or foam, is actuated automatically by the hazard system in critical areas. A malfunction in the vapor detection system is indicated by the VAPOR DETECTION MAL indicator on the LCCFC.

FIRE SENSING EQUIPMENT.
Refer to paragraph 1-68 for information on fire sensing equipment.

FIXED VAPOR SENSING EQUIPMENT.
Refer to paragraphs 1-69, 1-69A, 1-709 1-70A, and 1-257 for information on fixed vapor sensing equipment.

VAPOR DETECTOR ANNUNCIATOR PANEL.
A vapor detector annunciator panel (figure 1-61), indicates the concentration of propellant vapors throughout the launch duct area, fuel and oxidizer pump rooms and silo equipment area level 6. Toxic vapors are indicated by a red indication or a fluctuating reading on the VDAP and the applicable hazard checklist must be entered. A fluctuating reading is a detectable needle movement for a full sample period - approximately 15 seconds - as the MSA progresses through its sensing cycle. (The difference in humidity between sampled areas may result in oxidizer toxic meter fluctuations up to 1 PPM. Fluctuating oxidizer toxic meter readings not exceeding 1 PPM should not be regarded as a hazard indication or MSA malfunction. This 1 PPM fluctuation may be allowed in addition to stable meter drift indications.) A stable reading on all sample levels is indicative of meter drift and not the presence of toxic vapors. A stable reading is one with no detectable needle movement from its reference point, except normal momentary movement while cycling from one location to the next. A vapor hazard checklist need not be accomplished for a stable reading below the alarm level (5 PPM). After MCL 3235 a dimly lighted red indicator will designate level being sampled by the MSA. This indication is not to be interpreted as presence of toxic vapors. (After MCL 3252) VAPOR DETECTOR ANNUNCIATOR PANEL, A vapor detector annunciator panel (figure 1-61A), indicates concentration of propellant vapors throughout launch duct area, tuel and oxidizer pump rooms, and silo equipment area level 6. Toxic vapors are indicated by a meter indication on VDAP and applicable hazard checklist must be entered. The selector switch on VDAP is normally set to sample EF-102 exhaust (silo level 5). If a meter reading is detected (below alarm level), the selector switch will be manually cycled through all selector positions (a minimum of 15 seconds each) to check for meter drift. A stable reading on all sample positions is indicative of meter drift and not the presence of toxic vapors. A stable reading is one with no detectable needle movement from its reference point, except momentary movement when selector switch is moved from one selector position to the next. A vapor hazard checklist need not be accomplished for a stable (meter drift) reading at all selector positions below the alarm level (5 PPM). (The difference in humidity between sampled areas may result in oxidizer toxic meter fluctuations up to 1 PPM. Fluctuating oxidizer toxic meter readings not exceeding 1 PPM should not be regarded as a hazard indication or MSA malfunction. This 1 PPM fluctuation may be allowed in addition to stable meter drift indications.

KLAXON AND SURFACE WARNINGS.
Klaxon horns are located throughout the complex and are used to warn personnel of a hazard and alert them to EWO messages. A siren and beacon (3 lights) are located topside. The siren and beacon are controlled manually by the SURFACE WARNING CONTROL and SURFACE WARNING SIREN CONTROL pushbutton indicators on the LCCFC. Under normal conditions the SURFACE WARNING CONTROL is not lighted and the topside beacon is lighted green. When pressed once the SURFACE WARNING CONTROL lights amber and the amber beacon is lighted. When pressed twice the SURFACE WARNING CONTROL lights red and the SURFACE WARNING SIREN CONTROL lights white causing the red beacon to flash and the siren to be activated. The siren can be turned off and on, as desired, after the SURFACE WARNING CONTROL is lighted red. The surface warnings are used to warn personnel topside of a hazard and to alert them to EWO messages. The surface warnings may also he used, by cycling the siren and red beacon on and off, to notify personnel to return after topside evacuation. (After MCL 3304) An Emergency Warning Siren is mounted topside to supplement the existing siren and is used for notification of nearby civilian communities/landowners of potential hazards. The Emergency Warning Siren is controlled from the FPCB.

AREA SECURITY SURVEILLANCE EQUIPMENT
The area security surveillance system is a ground electronic system, operating on the doppler principle, to provide security surveillance within specified areas of the launch complex. Visual and audible alarms are provided in the control center which are activated when an intrusion occurs in any of the monitored areas. All indicators and controls are mounted on one annunciator panel located on the MFL rack above the MFL-1 drawer.

Three areas are covered by the system with each area having a module containing the indicators and controls for that area. The areas of coverage are as follows: sector one, control center air intake and escape hatch; sector two, south and west sides of the silo closure door; and sector three, north and east sides of the silo closure door.

Normal 120-vac power is supplied to the system through circuit breakers on AP-1 and CC-3. The 120-vac power is rectified by the system to operating voltage. Two nickel-cadmium batteries under constant trickle charge, on control center level three, automatically provide two hours of emergency operation in the event of facility power failure. No system alarm indications will result from power transfers.

PROTECTIVE CLOTHING AND EQUIPMENT
Protective Clothing and Equipment allows entry into areas where propellant vapors may be encountered. Category I equipment (RFHCO) provides full protection from liquid propellants and propellant vapors. Other categories provide varying degrees of protection designed to fit the circumstances. Figures 1-62 through 1-66 list the categories and procedures for use.

Checklists and maintenance technical orders specify protective equipment requirements for specific operations. These requirements must be complied with, except when it is desired to wear protective equipment providing a higher degree of protection.

ROCKET FUEL HANDLER'S CLOTHING OUTFIT.
The RFHCO is a complete leakproofed environmental ensemble consisting of a form-fitting suit, underwear, socks, boots, gloves, and a self-contained environmental control unit (ECU). A communications capability through the RTMN is built into the RFHCO.

The following requirements must be met while performing Category I operations in the silo, (For additional information reference T.O. 21M-LGM25C-2-12, Safety Precautions.)
 * a. A minimum of two individuals will be suited at one time and their ECUs will be activated simultaneously. The MCC will be notified of the activation time,
 * b. personnel will be recalled from the work area within 50 minutes from the time that the one hour ECU is activated and 110 minutes from the time the two hour ECU is activated. Where return travel time may be expected to exceed 10 minutes, the time limit will be reduced accordingly. This time is based on normal air duration of 60 minutes for the one hour unit and 120 minutes for two hour unit.
 * c. During all propellant handling operations, personnel in the control center will have rocket propellant gas masks immediately available but not necessarily on their persons,
 * d. During Category I operations in the silo, a minimum of two individuals will serve as standby men in the blastlock area. One of the two individuals will monitor the RTMN and the other will monitor the vapor detector annunciator panel for abnormal indications and report them as necessary. Additionally, a PC&E technician will be in the blastlock area any time Category I operations are in progress in silo. The technician will aid in donning RFHCO and will assume vapor detector annunciator panel monitoring duties if standby team is dispatched.
 * e. In the event communications are lost, or personnel are injured, the standby men will never attempt rescue until the MCCC has been informed and approves. A constant flow of information regarding the rescue will be transmitted by the team effecting rescue to the replacement standby men and the MCCC. This flow of information will continue until the rescue is completed and all personnel are in the blastlock.

SAFETY REQUIREMENTS

 * a. Safety in the complex depends, to a great extent, on proper supervision by the missile combat crew. The MCCC must assure himself that his crew members and maintenance personnel are capable of performing assigned tasks and that they know the proper safety procedure to follow. Supervision includes maintaining positive control of the movements of all personnel in the silo, demanding that proper communications procedures are followed at all times, using the BMAT and MFT to periodically monitor maintenance activities in progress, and stopping any activity when positive control cannot be maintained or safety is compromised.
 * b. The MCCC must ensure, through proper briefings, that all personnel entering the silo understand emergency communications procedures and evacuation routes. For example, personnel should understand that, when all AC power is lost, the VSS, klaxon, and elevator are Inoperative. They should know that they must contact the LCC on RTMN or WTMN since they cannot be signaled from the LCC. They should know how to exit the elevator if they are trapped in it due to loss of AC power. They must understand that the elevator will remain at the lowest occupied level (door closed) and will pick up personnel at higher levels if evacuation is necessary. They should understand the procedures to be used if they had to enter the launch duct as a last resort escape route. They should understand what to do in case they see a fire; notify the LCC, extinguish if possible, and evacuate when there is any doubt. Personnel must understand the most desirable destination for escaping a fire above them is the launch duet on level 8. They should also understand that launch duct entry at any level is acceptable if the situation will not permit safe evacuation to level 8 of the launch duct. Each individual escaping a fire must decide on which actions to take based on the particular circumstances of his situation. Personnel escaping a fire at a lower level should attempt to reach the control center. These examples by no means cover all the items of which personnel entering the silo should be made aware. The MCCC must use his own judgment in each situation.
 * c. Figure 1-65, Protective Clothing and Equipment Requirements, contains information as to site status in relation to the use of protective clothing and equipment. Condition GREEN means that the toxic analyzer portion of the fixed vapor sensing equipment is functioning properly, the vapor hazard sensing logic in CMG-2 is operational, a positive air balance is present between the silo equipment area and the launch duct, and meter drift, if present, is less than 5 ppm. Condition AMBER means that a negative air balance exists between the silo equipment area and the launch duct. Category IV is required for silo entry when the site status is AMBER. Condition RED means that all requirements for condition GREEN have not been met and additional protective equipment is required for silo entry. Generally, Category IV and the PVD are required for silo entry when the site status is RED. Protective equipment for every silo entry will be used as directed by figure 1-65. The MCCC may authorize the maintenance team chief to allow Category IV to be removed when maintenance is being performed in a confined work area. If Category IV is removed, it must remain readily available for use.

ESCAPE ROUTES

 * 1) Surface area escape is normally accomplished by exiting through the surface gate, If the surface gate is impassable, an alternate route is provided through a breakaway panel in the security fence. This panel is marked by a red pole and is normally located opposite the surface gate. (At some complexes there is a breakaway panel on all four sides of the security fence.) For emergency escape, pull the three pins on the inside of the red pole and one side of the panel will collapse.
 * 2) If personnel are unable to egress from the silo due to blast door 9 being inoperative or should they become trapped between blast doors, they should immediately phone for instructions. Portable hydraulic units are located in the blast lock junction (No. 201), and short cableway. Emergency instructions for opening the blast doors are attached to each unit. If trapped in blast lock (No. 202), first remove the wing screws from blast door 7 to provide air, then contact the LCC for assistance.
 * 3) Control center escape is normally accomplished by exiting through the blast lock area, up the access portal and out the surface gate. If the normal route is blocked the escape hatch on level 3 of the control center is used. Hatch opening instructions are posted on the escape hatch and are also contained in paragraph 4-21. Under post attack conditions personnel will wear available breathing apparatus and assure the body is covered as completely as possible with available clothing. After ascending the ladder, a retaining pin must be removed before the escape hatch grating latch can be removed and the grating opened.
 * 4) When communications with the control center can be established, escape from the silo equipment area is normally accomplished by use of the silo elevator to level 2 and then up the cableway and through blast door 9 into the blast lock area. If communications with the control center cannot be established, or if the silo equipment elevator is unusable, then the escape ladder is used. The elevator will not be used when there is a probability of a power loss, e.g. fire in diesel, switch gear, or MCC-l. If it is impossible to egress through door 9, or if passage to level 2 is blocked, then it may be necessary to enter the launch duct to await rescue or to obtain air. Entry into the launch duct will be directed by the MCCC if communications are available. When communications are lost personnel are authorized entry when necessary to save lives. The launch duct can be entered from equipment levels 2, 3, 5, and 8. Level 8 is recommended due to need to lower platforms at other levels. Levels 1 and 7 can also be entered if personnel in the equipment area have the access door keys for those levels in their possession. A decal, Emergency Lowering Instructions, is located on each platform annunicator panel for emergency egress Into the launch duct. To ensure a controlled and orderly evacuation, certain rules are provided and must be thoroughly understood by all personnel entering the silo. These rules apply upon hearing the klaxon or when made aware that a hazard exists.


 * (1) Establish communications with control center if situation permits.
 * (2) Don protective equipment when sight or smell confirms a hazardous condition and the evacuation route will not immediately remove you from the hazardous/contaminated area or when directed by MCCC.
 * (3) Monitor RTMN for additional instructions, if possible.
 * (4) Escape as directed by MCCC. Use elevator as directed.
 * (5) If communications with the control center cannot be established, and the escape ladder is unusable, evacuate to a safe location by the most expeditious means available.
 * (6) If in immediate danger, move out of danger area and notify the LCC of location as soon as possible.

If complex evacuation is required, personnel shall assemble 2000 feet upwind and await arrival of disaster response force, or notification that it is safe to return to complex.

EMERGENCY EVACUATION OF INJURED PERSONNEL
It may become necessary to evacuate injured personnel from silo equipment levels during a power outage. During an ac power failure, injured personnel will he evacuated to silo level 2 by means of the silo elevator. The elevator will he raised using the Launch Silo Elevator Emergency Hand Cranking Procedures posted on level 1D.

PERSONNEL ACCESS LIMITATIONS
The maximum number of personnel permitted past blast door nine, with propellant, ordnance or RV on board, will be limited to fourteen. The maximum number of personnel past blast door nine, with no propellant, ordnance or RV on board will he limited to twenty-five. During pad refurbishment at Vandenberg AFB refer to T.O. 21M-LGM25C-2-23 for access limitations.

EWO TOOL KIT
Tools specified as the EWO Tool Kit will only be used in conjunction with TO. 21M-LGM25C-121-1 and T.O. 21M-LGM25C-121-2. The tool box will be maintained in a locked and sealed configuration in control center. The following extra equipment will be maintained in the left side of the closed and sealed decontamination locker:
 * Two (2) five gallon cans, with flexible spouts.
 * Two (2) funnels.
 * Eight (8) chains, 6' long.
 * Four ('4) flexible hoses, 96" long.
 * One (1) flexible hose, 20' long.
 * One (1) Turbocharger Blocking Tool.

INTRODUCTION.
This section contains missile combat crew responsibilities for operating and maintaining the launch complex, including a brief description of primary and alternate functions. This does not preclude a crew member being called upon to perform other than his normal tasks in the event of an abnormal situation.

MISSILE COMBAT CREW COMMANDER.
The MCCC (AFSC 1825F) manages the missile combat crew in all operations and operates from the LCCFC during launch, malfunction isolation, and hazard emergencies. The MCCC maintains continual launch complex surveillance; assures that the missile and associated ground equipment are maintained in a constant state of readiness; verifies crew understanding and compliance with Air Force, SAC, and unit directives not covered in this manual; and ensures that a high degree of proficiency is maintained. The MCCC's duties are as follows:
 * a. Conducts crew changeover.
 * b. Conducts briefings.
 * c. Coordinates silo entry procedures prior to personnel entering silo area.
 * d. Coordinates and directs operational activities, including readiness monitoring and daily shift verification.
 * e. Directs hazard emergency procedures to maintain weapon system in a safe condition.
 * f. Directs malfunction analysis activities to return weapon system to state of readiness as quickly as possible.
 * g. Supports and monitors maintenance activities at launch complex to ensure safe and efficient performance.
 * h. Responsible for EWO fast reaction messages and positive control procedures.
 * i. Responsible for operational readiness inspections and other special exercises.
 * j. Responsible for launch and simulated launch procedures.
 * k. Responsible for security of launch complex.
 * l. Responsible for computing and cross-checking propellant loading computations with Site Maintenance Officer.

DEPUTY MISSILE COMBAT CREW COMMANDER.
The DMCCC (AFSC 1823F) assists the MCCC in performing his duties and must be able to accomplish all of these duties proficiently. In addition, the DMCCC must perform the following:
 * a. Submit required combat reports during actual or training exercises.
 * b. Coordinate checklist activities.
 * c. Man LCCFC during absence of MCCC from level 2 of control center.
 * d. Monitor progress of all launch sequences.
 * e. Monitor security television.
 * f. Maintain locator board for all personnel in launch complex.
 * g. Receive EWO messages and perform positive control procedures.
 * h. Monitors Communications Systems Status.

MISSILE SYSTEMS ANALYST TECHNICIAN.
The MSAT (AFSC 316XXF) maintains a constant check on status of the missile and OGE, and provides the MCCC with information on conditions affecting launch readiness. In the event of a malfunction, the MSAT isolates the cause to the extent of the equipment provided, and performs maintenance and emergency procedures. The MSAT is also responsible for:
 * a. Providing technical advice to MCCC and DMCCC.
 * b. Copying, decoding, and authenticating fast reaction messages (if on orders to perform these duties).
 * c. Performing malfunction isolation on his assigned equipment.
 * d. Monitoring maintenance performed at launch complex as directed by MCCC.
 * e. Manning ALOC during periods when MCCC or DMCCC is absent from level 2 of control center.
 * f. Monitoring and recording indications during launch sequence on his assigned equipment.
 * g. Performing daily shift verification.

MISSILE FACILITY TECHNICIAN,
The MFT (AFSC 541X0E) monitors operation of all facility systems equipment and associated support equipment at the launch complex. The MFT provides the MCCC with information on conditions that affect readiness status and launch capability of the launch complex, and troubleshoots all systems to isolate malfunctions to an end item or component. The MFT also takes necessary action during emergency procedures to return the launch complex to a ready configuration and assists other crew members as directed by the MCCC. The MFT is responsible for:
 * a. Providing technical advice to MCCC and DMCCC.
 * b. Monitoring FPCB.
 * c. Monitoring PDC-3.
 * d. Monitoring BM-1 panel.
 * e. Performing daily shift verification.
 * f. Monitoring operation of all air conditioners and associated equipment.
 * g. Monitoring operation of domestic water system, industrial water system, cooling water system, chilled water system, fire water system, and sewage disposal system.
 * h. Monitoring operation of electrical power distribution system, and transferring of power sources as necessary.
 * i. Monitoring operation of air compressor to assure air supply is sufficient to support launch and instrumentation.
 * j. Monitoring all hydraulic systems (HS-1, HS-2, HS-3, HS-4) to ensure proper operation of silo door, blast doors and dampers, and work platforms.
 * k. Copying, decoding, and authenticating fast reaction message (if on orders to perform these duties).
 * l. Manning ALOC during periods when MCCC or DMCCC is absent from level 2 of the control center.

Launch Checklist

 * NOTE


 * If flight simulation test is in progress, press MASTER RESET pushbutton on MGACG to terminate test,
 * Do not stop launch sequence after key turn except to react to indications that would affect successful completion of launch.
 * Do not perform Ordnance Circuit Test.
 * CAUTION


 * Do not launch with DEFLECTOR HIGH LEVEL lighted due to high water level.
 * Do not launch when atmospheric conditions exceed T.O. 21M-LGM25C-1-2 limits.

Remove security seals and insert keys into switches
 * WARNING


 * Do not continue checklist unless sortie is executed and an EWO commit time is available for launch.
 * If BVL is unlocked, do not reconfigure unless directed by Battle Staff.

For EWO launch, if circuit breaker trips off, attempt to reset. If circuit breaker does not reset, continue checklist.
 * NOTE


 * If OPERATE OK on the BVLC does not light in step 5, verify that the proper code is inserted.
 * If proper code is not inserted, press OPERATE INITIATE to not lighted, enter proper code, and reaccomplish step 5.
 * If OPERATE OK does not light, refer to figure 2-11 of T.O. 21M-LGM25C--121-1 for EWO launch. Notify command post of type deviation, ETOR. and intent to perform TCCPS. Post ETOR to EWO document. For peacetime launch refer to T.O. 21M-LGM25C-2-26.


 * WARNING

EWO launch: If sequence does not start after coordinated key turn, refer to Fig 2-1. Notify command post of type deviation, ETOR, and intent to perform TCCPS. Post ETOR to EWO documents.
 * Insure key turn time is in accordance with current EWO directives.
 * Simultaneously (within 2 seconds) turn keys for 5 seconds or until sequence starts.

PEACETIME launch: If abnormal indications occur prior to step 8, report to Launch Director and proceed as directed.
 * If launch sequence does not continue to liftoff, refer to HOLD or ABORT checklist, as applicable.
 * If LCCFC Launch Sequence Go indicators stop for 35-40 seconds with no hold indicator, refer to HOLD checklist.
 * WARNING

BATTERIES ACTIVATED .................................. Lighted 9..	APS POWER..............................................Lighted 10.	SILO SOFT...............................................Lighted ii. GUIDANCE GO, .............................. . ............ Lighted 12.	1 FIRE ENGINE ................. ............................... Lighted 13.	LIFT-OFF ................................................ Lighted NOTE LIFT-OFF indication is present at this time.
 * Insure key turn time is in acc
 * Disregard the LCCFC ABORT indication, if a
 * Immediately perform Post Launch checklist.

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