Impossible turn practice at 500ft

NordicDave said:
Agree.. My instructor told me, upon engine out the insurance company now owns the plane. It's your job to land it as safely as possible. That took a lot of stress off my back as a student pilot.
Click to expand...
Yep. I tell people if the engine dies it's my job to ensure everyone safety exits the insurance company's airplane.



Sent from my SM-G950U using Tapatalk
 
Last edited:
As an exercise it might have been interesting to try some different techniques. For instance the immediate steep turn costs a lot of altitude which is stored energy. What if a shallower turn was made at best glide and not in such an all fired rush conserving as much altitude as possible and riding any wind that is presumably blowing in a favorable direction?

Maybe not any better but it would be neat to at least just give it a try for comparison.
 
Silvaire said:
As an exercise it might have been interesting to try some different techniques. For instance the immediate steep turn costs a lot of altitude which is stored energy. What if a shallower turn was made at best glide and not in such an all fired rush conserving as much altitude as possible and riding any wind that is presumably blowing in a favorable direction?

Maybe not any better but it would be neat to at least just give it a try for comparison.
Click to expand...

If there's a nice landing spot a mile left or right of your field, that would work nicely. The steep turn (actually a tear drop sort of maneuver) is to get you aligned with the runway you took off from, or close to it on a parallel taxiway. Shallow turn will consume less altitude (you're giving up less lift vector to the turning vector) but will consume more time and lateral space.

All of this is, of course, subject to all sorts of weather an geography conditions as well as pilot skill. An engine out situation is a really poor time to try new things to see if you can do it.

John
 
The best lesson I learned from this practice, is that I wont try it in real life unless lightweight and at 1,000ft or more altitude.
 
motoadve said:
The best lesson I learned from this practice, is that I wont try it in real life unless lightweight and at 1,000ft or more altitude.
Click to expand...

I think the dangerous assumption here is that when it happens in real life, you’ll have time to go through a “decision tree” to work your way to a proper course of action, and then carry it out.

Whereas in real real life, the tendency is to revert to reflexive behavior - most often, after a brief delay, to do whatever we’ve been trained to do.

It often been said that there’s no harm practicing returns to the airport after engine failure. The harm is that if that’s what you’ve been practicing, that’s what you’re likely to try in a real emergency. And in real, real life, the reflex to turn around can have dire consequences unless perfectly executed in the one shot you have.

As an aside, why would being “lightweight” matter?
 
Last edited:
Lightweight vs heavy or at gross of course matters, stall speed for starters, glide ratio its improved too, so the chances of making it are much better.
 
jsstevens said:
...An engine out situation is a really poor time to try new things to see if you can do it.

John
Click to expand...

Yea I'm not talking about "engine out" I'm talking about the simulation exercise that the OP was conducting, using the different technique of shallow bank to see how it compares to the extreme turn that he was executing. We can theorize all we want but by actually doing it we'd have hard evidence one way or another. This could probably be done by anyone at a safe altitude as you're just looking to compare total altitude lost through the turn and whether or not you could arrive at the same point with more or less altitude remaining.
 
FastEddieB said:
I... The harm is that if that’s what you’ve been practicing, that’s what you’re likely to try in a real emergency. ..
Click to expand...

Valid point and if anything is going to get you it's the stall/spin, the likelihood of which increases if you are pulling a maneuver like this. In fact it just happened this week with the two guys that were taking their deceased father's ashes up to be spread. Engine quit, turned back, spun in and one of the brothers got killed - and he was a National Guard Blackhawk pilot from what I've read so don't think it can't happen to you just 'cause you're a good stick.
 
Silvaire said:
Engine quit, turned back, spun in and one of the brothers got killed - and he was a National Guard Blackhawk pilot from what I've read so don't think it can't happen to you just 'cause you're a good stick.
Click to expand...

Well I wouldn't assume a correlation between Guard helo pilot and fixed wing skill/experience.
 
Silvaire said:
As an exercise it might have been interesting to try some different techniques. For instance the immediate steep turn costs a lot of altitude which is stored energy. What if a shallower turn was made at best glide and not in such an all fired rush conserving as much altitude as possible and riding any wind that is presumably blowing in a favorable direction?

Maybe not any better but it would be neat to at least just give it a try for comparison.
Click to expand...
This subject keeps coming up.

In the paper The Possible 'Impossible' Turn on the following Website, the author shows that 45 degrees is the bank angle that gives the least altitude loss in the turn:

http://www.nar-associates.com/technical-flying/technical_flying.html

An instructor I know graphed the altitude loss as a function of bank angle, which showed it to be a broad minimum, so the bank angle doesn't have to be exact.
 
FastEddieB said:
I think the dangerous assumption here is that when it happens in real life, you’ll have time to go through a “decision tree” to work your way to a proper course of action, and then carry it out.

Whereas in real real life, the tendency is to resort to reflexive behavior - most often, after a brief delay, to do whatever we’ve been trained to do.
Click to expand...

That's a good point, and something that's always left out of this discussion. Proper training in this scenario would include looking at the altimeter as the first step. You should train that "below XXX feet AGL, I can't return to the field."

Very few people train for any kind of emergency on take off, so training *any*thing would be an improvement.
 
motoadve said:
The best lesson I learned from this practice, is that I wont try it in real life unless lightweight and at 1,000ft or more altitude.
Click to expand...
If the glide angle exceeds the climb angle, which is often the case, then more altitude hurts instead of helping, because it means that the higher you climb, the less likely you are to be able to glide to the runway.
 
Palmpilot said:
If the glide angle exceeds the climb angle, which is often the case, then more altitude hurts instead of helping, because it means that the higher you climb, the less likely you are to be able to glide to the runway.
Click to expand...
How can more altitude hurt? You can always burn altitude, but you sure can't create it. Perhaps you mean that your distance from the field may be awkward if you climb steeply.
 
Kenny Phillips said:
How can more altitude hurt? You can always burn altitude, but you sure can't create it. Perhaps you mean that your distance from the field may be awkward if you climb steeply.
Click to expand...
The problem is not climbing too steeply, it's gliding too steeply.

If you climb straight out, then you are not only increasing your altitude, you are also increasing your distance from the airport. Under the existing conditions at the time (aircraft performance, wind, density altitude, etc.), if the shallowest glide angle that the plane can achieve is steeper than the steepest climb angle that the plane can achieve, there will come a point beyond which you can no longer glide to the runway after the turn-back.

When this problem exists, one way to mitigate it would be to climb in the pattern.
 
RoscoeT said:
Well I wouldn't assume a correlation between Guard helo pilot and fixed wing skill/experience.
Click to expand...

My only point is that skill/experience doesn't mean you can't possibly end up falling out of the sky like a lawn dart in this kind of situation. It happens.
 
Palmpilot said:
The problem is not climbing too steeply, it's gliding too steeply.

If you climb straight out, then you are not only increasing your altitude, you are also increasing your distance from the airport. Under the existing conditions at the time (aircraft performance, wind, density altitude, etc.), if the shallowest glide angle that the plane can achieve is steeper than the steepest climb angle that the plane can achieve, there will come a point beyond which you can no longer glide to the runway after the turn-back.

When this problem exists, one way to mitigate it would be to climb in the pattern.
Click to expand...
Perhaps a drawing will help. The purpose of this is to show what can happen when the best climb angle the plane can achieve under the existing conditions is less than the best glide angle the plane can achieve.

Below is a profile view of a takeoff with turn-back. I have drawn it so that if the climb angle was greater than or equal to the glide angle, then the plane could make it back to the runway. Because the actual climb angle achieved is shallower, the best the plane can do is land short of the runway. (Angles are exaggerated for illustration purposes.)

climb-vs-glide-png.66770


Notice that even with the climb and glide angles shown, the plane could have made it back if the turn-back had started right over the departure end of the runway. That illustrates that the extra altitude achieved by climbing farther out not only didn't help, it actually made things worse.
 

Attachments

  • Climb vs Glide.png
    Climb vs Glide.png
    3.8 KB · Views: 34
You must log in or register to reply here.
Back
Top