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had been destroyed; however, inepection of recovered duct sections and the outﬂow control valve disclosed no indication of smoke or fire damage.

Only three items associated with the autopilot system were recovered and these were badly crushed. All recovered instrument system components were destroyed by impact with the exception of the two fluxgate compass transmitters.

The control surface booster assemblies had suffered moderate impact damage, which prevented their being tested as complete assemblies. However, indiVidual components capable of operation were given functional tests and those which could not be tested were dismantled and examined in detail. All discrepanc1es noted were attributed to crash impact damage With the exception of a failed electrical lead at the load sensor of the elevator booster assembly.

The load sensor was subsequently examined by the National Bureau of Standards whose report states, in part, "The break in the stranded Wire in the sensor unit was probably caused by several cycles of reversed bending, rather than by a Single tenSile or bending load."

The left air compressor assembly of the air start system was recovered at toe left wing impact Site. The compressor had been consumed by fire; only an ash residue remained which readily broke and flaked away when the assembly was removed for shipment. The right compressor assembly was demolished by impact but showed no endence of fire. Both of the right air bottles remained intact in the No. l; nacelle and still retained an air charge of urﬂmown amount, which was releaSed as a safety measure before removal of the wreckage. Both of the left air bottles Were also recovered. One was found separated from the wing structure at the impact site. It was slightly dented and the air lines had been torn off at the ﬂanges. There was no swidence of fire. The second bottle was still in pos1tion in No. l nacelle.

The fire bottles of the N0. 3 nacelle had not been discharged electrically but they had been broken by impact forces and contained no extinguishing agent. The bottles from the No. 2 nacelle had been involved in fire and both discharge heads had been fired. These were examined by the manufacturer who concluded that the outboard unit probably was discharged as a result of thermal discharge of the actuating cartridge and that the inboard hﬂl‘b was discharged through the safety disc by exceSSive pressure resulting from the fire, the actuating cartridge being subsequently discharged by action of the fire. Both rotary selector valves of the extingUishing system were recovered and their internal porting was determined to have been normal.

Two oxygen oottles (1800 p.s.i.) were recovered minus their regulator caps, which had been broken off. One crew bottle (39-h cu. ft.) was recovered only slightly damaged and with its valve 11 the Open poSition. The flight engineer's oxygen panel was found badly crushed. The oxygen mask was still attached to the regulator. No body tissue was found in or around this mask. Five additional masks were recovered in a torn condition with face glasses mlSSlng; none of these had students of human tissue on their inner surfaces.

The four fueling valves were functionally checked and then dismantled and inspected. Each valve required replacement of its impact damaged solenozLd, after which its mechanical functioning was found to be within operating limits. Inspection disclosed no defects or abnormal wear. No Significant contaminants were found Within the valves.