Page:CAB Accident Report, Slick Airways Flight 25C.pdf/2

-2- 115-volt, three phase inverters for radar, radio and flight and engine instruments. By a system of switches, the instrument, radio and NESA inverters may be utilized : supply AC power for other than their normal functions during emergency situations. All four inverters initially checked out satisfactorily during the ground checks following the landing at Albuquerque. Further troubleshooting by the flight engineer and local technicians did not disclose the engin of the electrical malfunctions.

When initial troubleshooting failed to bring the radios back to service, Captain MacCallum contacted the Slick Airways offices at San Francisco International Airport. Arrangements were made to dispatch a repairman to Albuquerque. Another Lockheed 1049H Silck 25C was to be dispatched to Albuquerque from Dallas, Texas. Captain MacCallum was instructed to transfer the cargo from Slick 40Z to Slick 25C and ferry Slick 40Z to San Francisco International Airport for maintenance.

At approximately 1500 m.s.t., February 2, the crew of Slick 40Z decided to obtain quarters for crew rest and departed the airport for a motel.

At approximately 2200 m.s.t., February 2, the Slick repairman arrived at Albuquerque to begin repairs of the radio equipment aboard Slick 40Z. He determine that the power supply units for both VOR navigation receivers were burned out; the power transformers for both ADF receivers were burned out; and the ILS glide slops receiver had burned out tubes and filter condensers.

Subsequently, Slick 25C, the replacement aircraft, arrived from Dallas and the transfer of cargo from Slick 40Z was begun.

When contrinued troubleshooting by the Slick repairman failed to correct the malfunctions, the No. 2 VOR power supply unit and the complete No. 2 automatic duration finder unit were replaced with units from Slick 25C. On completion of the radio repair and troubleshooting procedures, Slick 40Z had two functioning VHF transmitters and receivers, one functioning VOH receiver installed in the No. 1 or pile position, and one functioning ADF receiver installed in the No. 1 position. The glide slope receiver was inoperative. No tasting was performed on the marker beam receiver since its power source is direct current (DC) power which was not involved in the previous electrical malfunctions.

At approximately 0300 m.s.t., February 3, the crew of Slick 40Z returned to the airport.

Because of space limitations aboard the replacement aircraft, 3,750 pounds of cargo consisting of two missile motors were reloaded aboard Slick 40Z with the knowledge and consent of Captain MacCallum. Arrangements were made with company person to have a truck meet the aircraft at San Francisco International Airport to off-load the motors.

The crew checked the current and forecast weather conditions for the route and for the San Francisco terminal several times while at Albuquerque, the last check being made just prior to departure. This last weather check indicated essentially unrestricted conditions of ceilings and visibility at stations along and near the proposed route. The San Francisco weather at 0800 m.s.t., was 5,00 feet scatten clouds; estimated 14,000 feet overcast; visibility 2 miles in ground fog and smooth temperature 53 degrees; dewpoint 52 degrees; wind calm. The valid San Francisco terminal forecast for 1200 to 1600 m.s.t., was ceiling 5,000 feet broken clouds; visibility 7 miles; occasional very light rain