Most efficient bank in takeoff engine failure

R

rookie1255

Pre-takeoff checklist
Joined
Jul 13, 2013
Messages
108
Display Name
Display name:
rookie1255
Out of curiosity, does anyone know the most efficient bank angle to return to the airport if one has an engine failure on takeoff?

I know the best answer is almost always to find a landing spot straight ahead. I also know that the actual turn is a lot more than 180 degrees. After factoring in aligning with the runway and corrections it can be about 270 degrees.

So if you try to make it back with a shallow bank, your turn rate is slower but your descent rate is slower also. A steep bank will get you there sooner, but you will lose altitude faster.

Is there an optimum bank angle (maybe standard turn rate?) where you lose the least amount of altitude for the turn rate? For the sake of this argument we're going to say you're at a high enough altitude to make it back.
 
Whatever does it.

Ain't paint by numbers.
 
I've been told that a steeper bank is better than a shallow one because you spend less time gliding away from the airport.

But I cannot prove this mathematically or in flight, so :dunno:

-Skip
 
Got it. Found it in "Glide Speed and Bank Angle ," thanks.
 
For gliders, if the tow rope breaks at between about 200 and 400 feet, a bank angle of 45 degrees is suggested as being optimum when doing a 180 turn-back. [http://www.gliderbooks.com/downloads/M_Ch8.pdf] I do not know whether this is applicable to aircraft with lower L/D. Possibly a link to the relevant computation appears in the impossible turn thread.
 
Jim Logajan said:
For gliders, if the tow rope breaks at between about 200 and 400 feet, a bank angle of 45 degrees is suggested as being optimum when doing a 180 turn-back. [http://www.gliderbooks.com/downloads/M_Ch8.pdf] I do not know whether this is applicable to aircraft with lower L/D. Possibly a link to the relevant computation appears in the impossible turn thread.
Click to expand...

It does, and the calculation showed 45 degrees to produce the least altitude loss.

http://www.pilotsofamerica.com/forum/showpost.php?p=1908446&postcount=35
 
I've tried it in the Redbird FMX sim just for fun a few times. 45 degrees bank seems to be the best option.

My opinion though is that it's not called the Impossible Turn for nothing... You're probably not going to make it and are probably going to spin it into the ground. It happened at least a few times already this year with highly experienced pilots.
 
Gubbins said:
I've tried it in the Redbird FMX sim just for fun a few times. 45 degrees bank seems to be the best option.

My opinion though is that it's not called the Impossible Turn for nothing... You're probably not going to make it and are probably going to spin it into the ground. It happened at least a few times already this year with highly experienced pilots.
Click to expand...


Try it in a real plane, redbird isn't always realistic.
 
The answer to life and the universe is 42.

So I'm going with 42 degrees. :fcross:
 
James331 said:
Try it in a real plane, redbird isn't always realistic.
Click to expand...

Agree...but

Try it with an AOA indicator.

Might surprise you. And might learn a bunch now matter what plane u have.
 
Well, my guess (and I can prove it) is the MOST efficient bank is zero degrees.


You're welcome.
 
Captain said:
Well, my guess (and I can prove it) is the MOST efficient bank is zero degrees.





You're welcome.
Click to expand...


Technically inverted and not having to push to almost completely unload the wing but letting the airfoil do that for you, with gravity assisting, to follow a pure ballistic arc, would result in slightly higher efficiency than having the elevator fighting against the wing's lift and resulting drag of both the lift from the wing and the elevator acting against the weight of the nose.

But I suspect that in the short period of time available, the roll itself would induce enough drag through extended ailerons and poor pilot technique that the induced drag would negate the benefit from being inverted for only a few seconds.

Probably the best an average pilot would have time to do reasonably well without practice, would be 90 degree knife edge and a little bottom rudder to start the momentum of the nose down.

That'd result in the prettiest ballistic arc, and the fastest speed at impact without shedding much energy at all, thus, the most efficient.

:)
 
You must log in or register to reply here.
Back
Top