Paolo Bottura4 months ago Hi Dick, I refer to your answer to peter's question about the sequence "flaps 10 deg-gear up-flaps 0 deg: in your opinion does it apply to any aircraft for short field take off or is it for the Mirage only.
Paolo - Italy
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Hi Paolo,
So, with respect to gear retraction timing I would first like to restate the basics:
On a short field takeoff, the first part of the climb (1st segment) is about clearing the close-in obstacles. We need lift to do that, so we do not touch the flaps until clear of these inner obstacles. The legacy argument for raising the gear (including the current POH for the PA46) suggests getting the gear up first, I suspect because the writer of the POH is concerned about the drag of the gear which produces no lift; good point, but consider this: firstly, when the gear is in motion (going up) drag actually increases a very slight amount. This is due to the main strut fairings which supplement the manual gear extension in the event of an hydraulic failure. Secondly pilots tend to loose focus on pitch attitude at this critical time and inadvertently relax back pressure on the control wheel, which can lead to a serious accident. For these reasons I suggest a slight delay before doing anything and simply focus on proper pitch attitude and airspeed. I also recommend a slightly different order than the POH. The order of events during clean-up is not critical if the pilot waits until the 1st segment climb is completed. I suspect that in any fixed wing aircraft 20 degrees of flaps will ordinarily produce more drag than the extended landing gear; also, in the PA46 there will be an aural alert for gear not extended if the gear is retracted prior to selecting 10 degrees of flaps. Since the obstacles are cleared at this point, by definition the first segment climb is completed. At this point I recommend lowering the nose to 8 1/2 degrees up, and bring flaps to 10 degrees; then retract the gear and raise the flaps to zero degrees. No need to wait for gear to finish before going to zero flaps unless you have hydraulic flaps.
All PA46 aircraft operate this way, however, in any other case I suspect some study of the aircraft POH and possibly some experimentation with gear and flap retraction at a safe altitude under the supervision of an experienced instructor could answer the question for other types of aircraft.
Fly Safely - Train Often
DR
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