Practicing the "Impossible Turn"

Tokirbymd said:
If you’re trimmed for Vy which is usually close to best glide then even if power quits you’d have to fight the trim to get it slower no?
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Best glide is usually between Vx and Vy. IMO best glide in this situation would be a mistake. Distance isn't the goal, avoiding an accelerated stall is. Leave the trim at Vy so you have the extra speed as a buffer to maneuver.
 
Tokirbymd said:
If you’re trimmed for Vy which is usually close to best glide then even if power quits you’d have to fight the trim to get it slower no?
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Problem is, you're nose up at Vy. When the engine sputters, the airplane is going to decelerate until the nose drops pretty far. So you're decelerating that whole time. Once the nose is down, you'll eventually accelerate back to best glide (if you allow that to happen), but you're gonna lose a fair amount of altitude before you're stabilized at best glide. Unless you immediately push the nose down when the engine stumbles. Which <almost> nobody does, because of denial, then checking the mags, fuel pump, and fuel valve.
 
Dont do it, this is what I learned from practicing it at 500ft AGL, initially I thought I could make it easily and my first 4 attempts did not worked, made 12 more and was able to make 8 of them, but I knew it was happening. I would only try it at 1,000ft AGL or more.
 
Something else to consider: Assuming a straight-out climb, if the glide angle exceeds the climb angle (which depends on wind, density altitude, etc.), then additional altitude makes it less likely that you will be able to make it back to the airport.
 
write-stuff said:
What you practiced was a "possible turn". Impossible turns, by definition are impossible.
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I once had a lecture from a UNC computer science professor that says that a problem he had was theoretically unsolvable but he had a couple of grad students working on it.
I told him not to let them know it was unsolvable as it would just depress them.

I spent my career doing things that people claimed were impossible (such as with the impossible turn). Often, I would get the statement that the task I was performing was impossible after I had already done it.
 
flyingron said:
I once had a lecture from a UNC computer science professor that says that a problem he had was theoretically unsolvable but he had a couple of grad students working on it.
I told him not to let them know it was unsolvable as it would just depress them.

I spent my career doing things that people claimed were impossible (such as with the impossible turn). Often, I would get the statement that the task I was performing was impossible after I had already done it.
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I’ve done plenty of that in aviation. One of the reasons things are “impossible” is merely because we’re told it’s impossible, and obviously “they” know more than we do.

kinda like “NDBs are hard.”
 
flyingron said:
I spent my career doing things that people claimed were impossible (such as with the impossible turn). Often, I would get the statement that the task I was performing was impossible after I had already done it.
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The problem here is that people generally call the maneuver "the impossible turn". It's a misnomer. The FAA prefers "turn back" and I do, too. The turn back may be impossible, improbable, or possible. It all depends on a set of factors that many pilots are unaware of. Palmpilot, above, mentioned one of them - extra altitude doesn't necessarily increase your odds of success. It's a function of climb angle, glide angle, and altitude loss in the 270° turn (along with environmental factors and airport/runway geometry).
 
As others have suggested, "improbable turn" might be a more meaningful name for this maneuver than "impossible". It has been used successfully, so it's certainly not impossible. In other cases the pilot and passengers perished trying - this has happened much too often.

Add to that the surprise effect and adrenaline of a real and unexpected engine failure, and the fact that the airplane glides worse with an engine not making power vs. an engine with the power at idle, and I can't help but ask: why take any chances close to the ground if there is spot ahead of the wings where the landing is survivable?
 
Martin Pauly said:
I can't help but ask: why take any chances close to the ground if there is spot ahead of the wings where the landing is survivable?
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Excellent observation. If you have an acceptable landing spot ahead of you, that is generally your best option.

Land it straight ahead in a nice cow pasture, but ding up the nose wheel in the process, no problem. Insurance will pay for it. Make it back to the airport with an uneventful landing and you'll be the one footing the repair bill.
 
Palmpilot said:
It's not clear how to access that seminar on that Web page.
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Sorry about the delayed response on this. Here is a link to the program on “The Possible Turn”. He discusses the factors influencing likely success or failure and how to measure performance for your plane. He also gives some guidelines for deciding on both altitude over the end of the run and altitude to determine if this will be likely possible. (Sort of addresses one of the issues you raised earlier.)


https://www.mentorlive.site/program/20.html

I went out in my Cardinal the other day and I almost never would make the guidelines for a turn back in my 180 hp 1969 model.
 
I watched this video and found it interesting.

 
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