C. Malfunctions
ln the three man crew complement, the flight engineer copes with the malfunctions, and is capable of concentrating on the malfunction while the pilots fly the aircraft. However, in the two man crew complement, when one pilot is coping with the malfunction the other pilot must fly the aircraft sihgle handed.
The Three Man Crew Complement Coping with Malfunctions:
(extraction from a questionaire supporting the three man crew complement)
| "Aboard a 747, airframe vibrations not ezperienced on normal flights were felt and continued after flap retraction. When the flight engineer made an investigation, he found that the ground spoilers, which should not extend inflight, were deployed (ground spoilers should extend only on the ground where they reduce the lift generated by the wings and increase the effectiveness of the brakes). The flight engineer cut off the hydraulic power to the spoilers and retracted them." |
| "During cruise, there was a report from a stewardess in the aftermost cabin compartment that the aircraft was swaying in a strange manner and that it felt like a Dutch Roll. Since this swaying could not be felt in the cockpit, the night engineer and copilot took turns checking it out in the aft cabin compartment. Communicating over the interphone, the crew checked the control column and yaw dampers. There was indeed an unusual swaying from side to side and it was recorded in the flight log. On inspection on the grourld a malfunctioning yaw damper computer was found. The crew believed that they were capable of coping with the situation because of the three man crew complement and were able to take time to go to the cabin to check out the report which would have been very difficult in a two man aircraft." |
The Two Man Crew Complement Coping with Malfunctions:
(report from another company)
| "When a two man B767 was climbing through 10,000 feet, the cabin altitude climbed abnormally with the cabin rate of climb going off scale. EICAS indicateduCABIN AUTO INOPM, Auto 1 and 2 both had stopped functioning. Next the"CABIN ALTITUDE" message appeared fouowed by the Master Caution Light and Siren. Due to failure of both automatic systems, manual operation was tried with great difficulty but the cabin altitude continued to climb. Permission to stop climb and level off was gotten from ATC but with the change in engine power, cabin altitude operation became increasingly difficult. The copilot was ordered to concentrate on controlling the cabin altitude and finally manage to get it to somewhat stabilize at 5,000 feet. A decision to turn back was made and the copilot was busy controlling the cabin altitude until landing." |