Page:CAB Accident Report, Western Air Lines Flight 221.pdf/9

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be 1.4 knots per second. This acceleration would be slightly faster while the aircraft was on the ground. As the flaps transitioned from 50 degrees to 20 degrees, acceleration would increase to approximately 3 knots per second.

It was also stated that under these same go-around conditions, with 50 degrees of flap extended, an initial aircraft rotation of approximately five degrees would be necessary to establish a positive rate of climb. As the flaps were retracted to the 20-degree position an additional three degrees, or an angle of attack of approximately eight degrees, would be required to maintain the positive climb rate.

The landing gear and flaps are hydraulically operated by a constant pressure system with an operating pressure range of 2,600 to 3,050 p.s. 1. This pressure is maintained by two engine-driven hydraulic pumps. With both pumps operating, the flap retraction time from 50 to 20 degrees is approximately seven seconds; landing gear retraction time is approximately eight seconds. The landing gear actuation sequence is such that the nose landing gear is the first to respond after selection to the retract or extend position.

Procedures to be followed for a go-around from a normal approach (gear down, Maps 50 degrees, all engines operating), in effect at the time of the accident were set forth in two company manuals.[1]

On November 14, 1963, WAL Flight Operations Memorandum (No 63-27) was disseminated to all flight personnel. This memorandum changed the duties of the first officer and second officer with respect to throttle handling during takeoff, and gear retraction and extension for takeoff and landing. The applicable section of this memorandum is as follows</ref>

"4 Throttle Handling During Takeoff

In application of power during takeoff, the second officer instead of the first officer will follow up on the right-hand set of throttles (or left-hand throttles if the airplane is being flown from the right) and will make the final adjustment and setting in accordance with the command received ...

5. Gear Retraction and Extension

Hereafter, the retraction and extension of the landing gear will be handled by the first officer instead of the second officer. This will standardize gear and flap handling in all three pieces of equipment. In the DC-6B, this change will serve to equalize the work loads of the first and second officers especially during emergencies.


  1. 11/Go-around procedures listed in the WAL Pilots Manual, dated March 1963, were in part
    1. Apply necessary power and attain best climbing speed. . .
    2. Retract the wing flaps to the 20° takeoff flap position.
    3. Raise the landing gear as quickly as possible after obtaining a positive rate of climb.
    The go-around procedures outlined in the WAL DC-6B Airplane Manual, dated July 20, 1954, were in part.
    A. Apply full necessary power and attain best climbing speed
    B. Raise the landing gears.
    C. Retract the wing flaps to the 20° takeoff position.