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In a previous question the case about if a turnback would be feasible, specifically for a single engine aircraft, has been analysed.

But given a twin-engine general aviation aircraft and a single engine failure immediately after lift-off, considering that my Pilot handbook says:

A continued take-off is not recommended if the steady rate of climb according to "Section XX" is less than Y%.

Considering the quite dangerous setting, I would say that is quite impractical to go and check that table in such a situation.

What kind of indicators might I look for to check if it safe to continue? Should I learn by heart such table? (I am not sure this is practical either, is a quite complex table)

In case I am unsure what to do, apart from trying to climb for a while then turn around or immediately try land in front of me (granted that there is enough space), are there, generally speaking, other options?

In the accepted answer of the listed question is said that

It's not reasonable to try it [a turnaround] without knowing what altitude is needed for it at current conditions.

is it possible to estimate this quickly inside the cockpit?

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  • $\begingroup$ point is with a single engine a plane should be able to maintain level flight which allows for more freedom than with no engines $\endgroup$
    – ratchet freak
    Commented Jun 11, 2014 at 11:17
  • $\begingroup$ @ratchetfreak that is what I thought, but that sentence in the POH made me think. $\endgroup$
    – Federico
    Commented Jun 11, 2014 at 11:19
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    $\begingroup$ Doesn't the "Section XX" have a table from which you can get the "Y" during preflight? $\endgroup$
    – Jan Hudec
    Commented Jun 11, 2014 at 20:08
  • $\begingroup$ @ratchetfreak: IIRC the rules only apply to transport category aircraft, but not general aviation. $\endgroup$
    – Jan Hudec
    Commented Jun 11, 2014 at 20:14
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    $\begingroup$ @JanHudec That's the exact point that I was going to make. You should look this up before every takeoff, just in case you need it! $\endgroup$
    – Lnafziger
    Commented Jun 11, 2014 at 21:01

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What you really should learn by heart is the flight speed for best climb with one engine inoperative. Try to trim that immediately and you will win more time to make a decision. The rest is really depending on circumstances: Is there a landing opportunity ahead? Are you high enough to do a 180 and land on the same runway in opposite direction? Or are you high enough (and the aircraft does not lose altitude) that you can fly a pattern and land normally?

Testing the aircraft at altitude with one engine throttled is highly recommended, but be aware that the remaining thrust / drag of the throttled engine might be different from that of the stopped engine.

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  • $\begingroup$ I believe if the propeller can be feathered, the difference will be reasonably small. $\endgroup$
    – Jan Hudec
    Commented Jun 11, 2014 at 20:07
  • $\begingroup$ @Jan Hudec: You are correct. But if you do not have much altitude and there is plenty to do in the cockpit, pressing the prop pitch switch long enough will not be first priority. Always plan for some non-optimal condition. $\endgroup$
    – Peter Kämpf
    Commented Jun 11, 2014 at 21:15
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    $\begingroup$ @PeterKampf i havent touched a multi piston prop in 9 years and i still have the "mixture, prop, throttle, dead foot dead engine, verify throttle, prop feather, mixture cutoff" muscle memory. $\endgroup$
    – casey
    Commented Jun 12, 2014 at 0:04
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After you've learned your airplane and its characteristics, you will know if something is not right. The decision to land, when that's something that can be safely done, is never the wrong one if you're not comfortable with your performance and problems can be checked out on the ground with nobody dying usually!

Regarding a safe altitude to turn around in... you need to know your aircraft to answer this, but it's not terribly difficult to learn. You can fly to a few thousand feet AGL (preferably with a CFI or other capable safety pilot), fly at whatever speed you climb at, pull your throttle out and see how much altitude you lose while doing a 180 degree turn (simulating turning back to your departure runway). Try this under different conditions (max gross weight vs. generally empty; high density altitude vs low for example) to learn how these factors affect your altitude loss. Then apply a safety margin.

I've been taught that a general figure (without recognition of the specific aircraft or conditions) is 500 feet. This is not to say a turn-around is safe at 500 feet! It's just a baseline of consideration. Other factors are going to include how much runway you're going to have if you're able to turn around!

One of my primary instructors, before every first launch of the day, had me go through an aborted landing briefing similar to: if we have an emergency below 500 feet we're going to land straight ahead. Below 700 feet, we're going to turn to the (left/right) and land on the crossing runway (my airport had 9/27 and 5/23). Higher and we will turn left/right and land on the parallel runway (9/27 R/L; easier to get to than a full 180 in-place).

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You are more likely to kill yourself in a stall/spin trying to turn back than you are from a forced landing straight ahead.

Since the altitude required to make a successful 180 turn is quite considerable the chances are if you are high enough you will be too far from the runway to make it back.

I remember seeing an article in plane and pilot magazine back in 1974 dealing with that topic and I seem to recall anything below 780ft AGL was a no-go

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  • $\begingroup$ If your angle of climb is better than gliding angle, at higher altitude you will be more likely to make it back. If it isn't, you won't, ever. Also beware that the minimum altitude depends very much on the aircraft and the weather, because density altitude affects rate of climb quite significantly. $\endgroup$
    – Jan Hudec
    Commented Aug 10, 2015 at 7:29

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