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With power off, is it possible to maintain constant altitude for some period of time, until the 1-G stall speed is reached, i.e. until the stall angle-of-attack is reached?

Implicit in the question is the assumption that the initial airspeed is above the 1-G stall speed.

quiet flyer
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    Why ask such a question? The answer seems completely obvious, but discussion under this related question https://aviation.stackexchange.com/questions/66366/what-is-the-regular-stall-speed-of-f-16-flying-in-a-straight-and-level-path?noredirect=1#comment173477_66366 suggests we may see some "interesting" answers posted. – quiet flyer Jul 09 '19 at 14:38
  • @AEhere -- modified. Anything else that you need to know? – quiet flyer Jul 09 '19 at 14:43
  • No, I just wanted you to avoid needless discussion by eliminating the trivial case. – AEhere supports Monica Jul 09 '19 at 14:49

2 Answers2

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Yes, assuming your are flying level with the engine running and then you turn the engine off, the following will happen:

  • Without power from the engine, the drag will cause the airspeed to decrease.
  • Lower airspeed at the same angle of attack implies less lift. Since you want to maintain altitude, lift needs to stay the same (your weight has not changed). Thus, you have to increase pitch.
  • Eventually, you will reach the critical angle of attack and flow separation will occur, i.e. you stall. The airspeed at which this happens is called the 1-G stall speed, although one can stall any speed.
Bianfable
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Yes, this is how you practice stall recovery.

  • reduce power to idle
  • continue pulling back (that is to say, increase angle of attack) to maintain altitude until stall warning sounds
  • recover by lowering the nose and then re-applying power
Jamiec
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  • Btw it's not how I usually practice stalls-- why worry about holding altitude exactly constant? Exactly what is gained by that? But it is indeed a common way to practice stalls. – quiet flyer Jul 09 '19 at 14:47
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    I didnt say "exactly constant". I said "maintain". If you constantly lose altitude while practising stalls it just prolongs the amount of time you're maintaining slow flight, and the possibility of an unexpected wing drop. – Jamiec Jul 09 '19 at 14:49
  • ... plus if you know how to practice a stall, then you know the answer to the question. – Jamiec Jul 09 '19 at 14:50
  • I don't mind the downvote for asking an obvious question, but if you are curious about the context and motivation, read the comments under https://aviation.stackexchange.com/questions/66366/what-is-the-regular-stall-speed-of-f-16-flying-in-a-straight-and-level-path?noredirect=1#comment173477_66366 . – quiet flyer Jul 09 '19 at 14:54