PPRuNe Forums - View Single Post - All those that flew for Discover (f)lying on the Penguin runs
Old 11th Mar 2014, 12:00
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Centaurus
 
Join Date: Jun 2000
Location: Australia
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Ah 'DS333" I remember that night well.
If I recall Ted didn't get the prop feathered so really didn't follow std eng fail proc's. The flaps on a Dove are like barn doors & they where left down during the entire sequence if my memory serves me correctly. The gear was a real pain at times to get pulled up.
They where lucky the old Dove stalled at 60 kts or so & with a large lumbering airframe the crash sequence would have been like in slow motion.
The BASIS report was most thorough and should still, in my view, be mandatory reading for all multi-engine flying instructors conducting initial twin training. The report said the take off charts were for a zero flap take off whereas the pilot used partial flap because that was what he was taught on his conversion. Also from memory, the windmilling drag from the failed engine prop was more than the drag experienced with gear extended.

The relatively successful outcome was because of the swift action by the pilot to reduce power on the live engine, thus avoiding a VMCA stall - in other words, he hit the roof of the first house with wings almost level which dissipated the energy by the time the aircraft hit the second house roof.

The report said later tests indicated an aborted in flight landing straight ahead on the remaining runway would have probably resulted in an over-run on to the Tullamarine Freeway. These flight tests done overseas at the request of BASIS revealed that a surprising amount of remaining runway is required to lose an engine shortly after lift off, have a reaction time delay of four seconds before bunting over to touch down in a flapless configuration and then apply brakes.

It was also found very difficult for a pilot to judge when actually airborne if there was sufficient runway to abort and land back on straight ahead particularly at night and pull up. Worse still if the runway surface was wet with rain resulting in loss of braking action..

The current teaching at most flying schools for engine failure still calls for a lengthy series of actions before getting around to feathering the prop. For example a typical brief is mixture up, pitch up, power up, flap up, gear up, identify dead leg dead side, confirm by slowly closing the throttle then finally feather.

That is all very fine with engine failure at a safe cruising altitude, but after lift off, unless the prop is feathered promptly as first action, then the windmilling drag will result in so much drag that speed loss is certain. Also, if the take off performance lift off speed is predicated on take off flap, to select flap up at a very low altitude before feathering will likely cause a sink rate unless adequate speed exists to allow for attitude adjustment.

It takes at least 15 seconds to get around to feathering a dead prop if the pilot goes through the whole drill dead leg - dead side etc, before actuating the feather system. That becomes a significant delay if the engine has failed soon after getting airborne. Flying schools should ensure students are aware of the vital difference in the speed at which a student must get the failed prop feathered during handling an engine failure shortly after lift off, as against a safe height where a more leisurely deliberate action is available and even an attempt at re-starting the engine.

Inevitably, there are a few seconds of "dead man's gap" immediately after lift off where the pilot has no choice except to land straight head and hope to pull up safely. That is why it is best to select gear up on attaining a positive rate of climb after lift off and thus accelerate more quickly through those few seconds, rather than deliberately leave the gear down with its attendant increased drag in case you want to land straight ahead.

Slight thread drift but the Ted Rudd Dove accident at Essendon is a fascinating study of an engine failure on take off and superb handling by the pilot to make a controlled crash with no serious casualties. Read the full report and learn a lot from it.

Last edited by Centaurus; 11th Mar 2014 at 12:22.
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