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I have heard it said on several occassion that when you are landing you need to control your descent with your throttle, and not with your pitch.

Two closely related questions that I think can be answered in one go:

  • Why do we use throttle instead of pitch to control the descent?
  • How does this work in practical terms? (How do you do it?)
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  • $\begingroup$ Oops, good catch. I didn't see that one pop up on the list of possible dupes when I was writing the question... $\endgroup$
    – Jay Carr
    Jun 22, 2015 at 20:33
  • $\begingroup$ This is a different way of wording the question, and since it didn't pop up in the possible duplicates, it would be good to leave open as a "sign post" to help others find the original question. I wouldn't delete it if I were you! $\endgroup$
    – Lnafziger
    Jun 22, 2015 at 21:16
  • $\begingroup$ @Lnafziger Ah...well, I guess so long as people know that it's a sign post and that I'm not actually lazy... $\endgroup$
    – Jay Carr
    Jun 22, 2015 at 22:43

1 Answer 1

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Your pitch is adjusted to maintain airspeed, whereas throttle and thrust are used to establish a rate of descent.

Shameless steal from KeithS comment below:

[Y]ou're gliding down to the runway, but you need a little engine power to keep a shallow glide slope because you aren't in an actual glider. The real explanation is that trying to use pitch to control glide slope causes dramatic changes in angle of attack, especially at the lower speeds used for approach and landing. This could cause a stall, or a severe loss of altitude. The throttle provides much more minute control over your angle of attack and thus your glide slope.

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  • $\begingroup$ Right, I'm asking why because it sounds really counter intuitive. $\endgroup$
    – Jay Carr
    Jun 22, 2015 at 20:12
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    $\begingroup$ It does, until you come to think of a landing as being a powered glide. That's more or less what it is; you're gliding down to the runway, but you need a little engine power to keep a shallow glide slope because you aren't in an actual glider. The real explanation is that trying to use pitch to control glide slope causes dramatic changes in angle of attack, especially at the lower speeds used for approach and landing. This could cause a stall, or a severe loss of altitude. The throttle provides much more minute control over your angle of attack and thus your glide slope. $\endgroup$
    – KeithS
    Jun 22, 2015 at 20:32
  • $\begingroup$ @KeithS Shameless stealing of your comment, but proper attribution. I hope you don't mind :) $\endgroup$
    – SentryRaven
    Jun 23, 2015 at 12:42
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    $\begingroup$ It's not about more minute control, it's about the fact that you are trying to manage your energy and your energy balance can only be changed by throttle. Elevators only control distribution of the energy between potential (altitude) and kinetic (speed). $\endgroup$
    – Jan Hudec
    Jun 23, 2015 at 12:44

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