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In two-engine aircraft with wing-mounted engines when one engine quits the aircraft will have a natural tendency to turn to the dead engine. So if you need to turn, it seems logical it should be easier to turn that way.

However in the discussion here is a comment:

By dinger on Monday, Aug 11th 2014 13:42Z:
SOP in a twin is NOT to turn in the direction of the failed engine. Right engine failed and they turned Right.

Is it really standard procedure, and if it is, what is the reason behind it?

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  • $\begingroup$ Example of an accident where the turn to the dead engine side was determined as one of the fatal factors en.wikipedia.org/wiki/%C4%8CSA_Flight_001 $\endgroup$ – Vladimir F Aug 13 '14 at 13:13
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    $\begingroup$ @VladimirF: I don't see that say they tried to turn anywhere, only that the aircraft banked because of the asymmetric thrust. $\endgroup$ – Jan Hudec Aug 13 '14 at 13:48
  • $\begingroup$ The investigators published the causes as follows: Failure to bank the plane towards the working engines side "Příčina nehody:... nenaklonění letadla na stranu pracujících motorů... " $\endgroup$ – Vladimir F Aug 13 '14 at 13:54
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    $\begingroup$ @VladimirF: Yes. But that means they failed to properly counter the torque, not that they tried to execute turn and did it wrongly. $\endgroup$ – Jan Hudec Aug 13 '14 at 14:03
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    $\begingroup$ The best place to look to see if this is actually required is in the POH / FOM for the specific airplane. I'd be surprised if the engine out procedures say that you are not allowed to turn into the dead engine though, but rather that you are required to keep a specific minimum airspeed so that it isn't an issue. $\endgroup$ – Lnafziger Jun 23 '15 at 18:08
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The AvHerald comment is correct, you generally do not want to turn towards the dead engine. The aircraft will tend to turn (both yaw and bank) towards the dead engine due to asymmetric thrust, allowing it to do so at low speed will make it difficult to end the turn, possibly to the point where you lose control. If you turn away from the dead engine, you'll have a tougher time getting into the turn, but the live engine will help you get out of it. That said, attempting low altitude turns with an engine out seems like a bad idea, you should concentrate on going straight and maintaining optimum airspeed to make sure you get some altitude

There are a couple of mnemonics when dealing with engine failures, like "dead foot, dead engine" (determining which engine failed) and "raise the dead" (keep bank towards the live engine)

I can only speculate as to why they chose to go right, either they wanted to avoid the populated area, or they were already unable to control the turn. The high density altitude would certainly affect the OEI performance as well, perhaps luring them into losing airspeed below Vmc.

Disclaimer: I'm not multi engine rated, and have no first hand experience. This is just what I've read.

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    $\begingroup$ FWIW, when I went through multi-engine training in the early 1970s, the common wisdom was to avoid turning into the dead engine, and that is what I taught as a multi-engine instructor. $\endgroup$ – Terry Aug 13 '14 at 18:37
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    $\begingroup$ flying 4 engined turboprops we were trained to prefer turning away from the dead engine. The aerodynamic issues are the same. I've shut down lots of engines and 1-engine out was not a significant control issue. I would not go to extremes to avoid turning into the dead engine, but I certainly made a conscious effort of smooth, shallow turns and perfect rudder control. An outboard dead engine got more attention. Gross Ham-fisted control input has caused completely avoidable crashes. $\endgroup$ – radarbob Aug 14 '14 at 23:49
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    $\begingroup$ Isn't this why Vmca should be observed, and not just stop turning one direction? $\endgroup$ – Lnafziger Jun 23 '15 at 18:07
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    $\begingroup$ @falstro As a former engineer and professional pilot, I am VERY much a "fly by the book" kind of person. The procedures are there for a reason. Want to live? Don't get too slow! :-) $\endgroup$ – Lnafziger Jun 23 '15 at 22:03
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    $\begingroup$ @falstro I know, and I'm just saying that if you don't go below Vmca then you don't have to worry about which way that you turn. In this situation, it would be a cardinal (even deadly) sin to let the speed drop, so you cannot let yourself get distracted to that point. Period! For me it is such a high priority that I can't even see it happening! $\endgroup$ – Lnafziger Jun 25 '15 at 18:13
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I was recently PIC of a twin Aztec, when I was on a single pilot IFR departure. At about 800 feet at gross weight, without warning there was a loud bang and the right engine quit.

I was able to make a wide left 270 tear drop turn into the good engine which was operating at full power.

My multi-engine training taught me the skills necessary to survive this failure. A turn in to the good engine is taught for a reason. Raise the dead...

This helps the rudder have the authority to over power the asymmetrical thrust of the good engine. I believe a turn into the dead engine may have resulted in loss of control, and death.

The main thing is DON'T PANIC... Fly the airplane...

The good Lord was in control as The aircraft was loaded at gross weight (5 passengers and baggage).

I was able to complete the turn and land safely opposite the direction of my departure.

The stall horn was chirping through out the shallow turn, but my airspeed was right at Vyse (blue line). We were NOT climbing. The cause of the failure has not yet been diagnosed.

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    $\begingroup$ Welcome to Aviation! This site is designed as a question-and-answer exchange, not a forum, and this is not really an answer to the question. Please take a look at aviation.stackexchange.com/help/how-to-answer for some tips on what's expected in an answer. $\endgroup$ – voretaq7 Jun 23 '15 at 20:49
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    $\begingroup$ I think that was a great story. $\endgroup$ – Zuzlx Jan 7 '16 at 20:29
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    $\begingroup$ All that training, and it was the good lord that saved the day. Amazing, but bit of a waste of money on flying lessons. $\endgroup$ – Jamiec Jun 8 '17 at 8:11
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A spin is an aerodynamic, stable maneuver where one wing stalls and the other continues flying. To practice this maneuver once, turn into the dead engine of a twin engine airplane, the spin will be textbook perfect and you'll be back on the ground very quickly.

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    $\begingroup$ lol, 'practice this maneuver once' $\endgroup$ – Martin James Jul 9 '15 at 13:48
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    $\begingroup$ But why does turning into the dead engine provoke spin more easily than turning into the live one? $\endgroup$ – Jan Hudec Jul 12 '15 at 16:37
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At low altitude eg on climb out, airspeed is low, no accelerated airspeed from prop on side of dead engine, if you turn into dead engine, airspeed over that wing drops even more and it will readily stall hence spin! With ample speed and altitude there should be no problem with a gentle turn.

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  • $\begingroup$ @Federico, I think the answer, as it stands, does add a lot. It explains the Caroline's non-answer. $\endgroup$ – Jan Hudec Jun 8 '17 at 9:27
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That’s kind of an old wives tale. The truth is you can turn into the dead engine, if you do it right.

Most certified twins are pretty well behaved airplanes with a failed engine, except at low speeds and low altitudes. Since control authority is more diminished here, there is s much greater tendency of the roll and yaw moments from the asymmetric thrust loading on the airplane to cause a departure from controlled flight. You must be very careful when handling these airplanes in this regieme of flight and never attempt to apply power below the minimum control airspeed with a failed engine as this is a death sentence in a twin. That being said smooth easy maneuvering of a twin at or above minimum safe single engine speed will be just fine, regardless of whether you are turning into the dead engine or not.

One key to performing the turn correctly is to keep the turn coordinated with the ball moved approximately 1/2 out of the center marks - “uncage the ball” - in the direction of the good engine. This will ensure no sideslip in the turn.

As part of a multi engine checkride, examiners will fail the critical engine in a left hand traffic pattern, forcing the pilot to turn into the dead engine in order to return and land. Examiners will also test things like engine failures in steep turns for MEI checkrides as well.

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    $\begingroup$ "except at low speeds and altitudes" -- nope. Outside of ground effect, the aircraft does not care how close the ground is. $\endgroup$ – davidswelt Apr 29 '18 at 14:27
  • $\begingroup$ Try that with an inoperative engine at or below Vmc and see how well that works out for you. $\endgroup$ – Carlo Felicione Apr 30 '18 at 5:06
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The reason is that Vmca is not a fixed value (despite the red line), and actually increases as you are banked more toward the inoperative engine. If you start from a position banked to the good engine, you will have more rudder authority if turning to the good engine.

This video does a good job of explaining this, and especially between 10-16 min shows why you want to maintain bank toward the good engine and it's effect on rudder use.

Remember that the red line speed is based on a very specific set of conditions.

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