Impossible Turn

Please do me (and yourself) a favor. If you’re not familiar with the “impossible turn”, read on, and get with a good instructor before your next flight (while I hope this article is useful, it’s no substitute for instruction). It’s imperative that you understand the dangers of the impossible turn. An experienced pilot died yesterday in a crash at my home airport (EMT). From initial reports, it appears he had an engine failure soon after takeoff and attempted the impossible turn from a low altitude.

The impossible turn refers to a maneuver where a pilot attempts to make a 180+ degree turn back to the runway after an engine failure. It’s called the impossible turn as it frequently ends in a stall/spin accident. Stall/spin accidents are much more deadly than a typical straight ahead crash. You may remember that I had an engine failure shortly after takeoff; my straight ahead crash landing totaled my airplane, but I was uninjured. I didn’t try the impossible turn for good reasons.

Why is it “impossible”?

After an engine failure soon after takeoff, a pilot must quickly lower the nose of the airplane to establish best glide speed. Failure to establish that will leave the airplane dangerously close to a stall. Delay is to be expected as a result of the startle response that occurs – your mind doesn’t want to accept your engine has just failed. At the same time, a turn is required: shallow banks reduce the likelihood of a stall, but increase the time and altitude lost; steep turns reduce the time and altitude lost, but at the cost of increased stall speed and likelihood of stall. All of this maneuvering is being done close to the ground, which creates sensations and cues that may cause a pilot to pull up into a stall or overbank the airplane. If the starting altitude was too low, even a perfectly performed turn will fail.

You should see this is a challenging maneuver that would have to be executed almost perfectly under the stress and shock of an engine failure. Stalls, spins, or even just steep banks all create high vertical velocities that make failure more likely to be a fatal mistake.

The desire to get back a runway is very strong. We perceive runways as safer than landing off field, but the maneuver to get you there is very dangerous. Even if the turn is successfully executed, you are also choosing a downwind landing. A downwind landing at 60 kts with a 10 kt tailwind will have twice the kinetic energy to dissipate (by the brakes or a crash) compared with the same landing with a 10kt headwind (energy increases as the square of ground speed – 70 kts vs 50 kts).

What should I do?

For me, the starting point of all engine out scenarios is the precision power off 180. You need to train your eye to what the engine out glide of your airplane is – what angles you can make and what ones you can’t. How can you adjust drag and flight path to reach a target? Once you can do that, you can start to consider more advanced scenarios.

For an engine failure after takeoff, the common guidance is to choose the best landing spot that is within your field of view ahead (about a 30 degree turn max). I recommend that pilots consider what options exist at the airports they operate from. Obviously the options depend on the rate of climb for your airplane and the glide ratio. For the planes I fly, departing runway 19 at EMT, once a landing on the airport property is no longer possible, the next option becomes the Rio Hondo wash that parallels the runway and then angles a bit to the right. The wash is wide and flat; even the overpasses seem to have enough space between supports for a typical wingspan. As you continue to climb, at some point a landing on the I-10 freeway might be an option (if the freeway is moving at normal speeds). If I am staying in the pattern or at least turning downwind, then a landing on runway 1 may become an option as I turn crosswind to downwind. By the time I am downwind abeam the runway, I can normally make an engine out landing onto runway 19 (though not always to the threshold).

Is it always impossible?

There are clearly cases where it is possible to make the turn, but for that to be an option, you need to meet several criteria:

  • You need to have briefed for the option before departure
  • There are no good options ahead
  • You need to be high enough to confidently make the turn
  • You need to have practiced the turn in the plane you are flying recently enough to be able to execute the turn
  • You need to be able execute as practiced under the stress

I frankly feel there are few pilots and situations where this is the right answer. If you really want to be prepared for this option, you’ll need to spend quite a bit of time with an instructor and doing solo practice. My experience says the practice with a pilot is one of the most challenging maneuvers to keep safe. For more information of how to determine the parameters, I suggest more reading.

 

Disclaimer

My thoughts are with the family and friends of the pilot. We may never know exactly what happened in the crash. We always hope that the NTSB is able to determine each link in the accident chain, but in small planes that lack flight data recorders, it can be harder. It is likely the NTSB will take a year or more before they publish a “probable cause”. I am speculating, but my ultimate goal is to help drive home the importance of thinking about options and avoiding the impossible turn, unless you are VERY sure of success. I hope you never have to face the scenario.

I did not see the accident. I was in a Cessna 172 with a student, ready for takeoff. The Pazmany PL-2 had been in the runup with us, but departed before us. We became aware of the crash when the tower controller told us to standby and that there had been an incident at the southeast end of the airport. We taxied back to parking and decided that even once the airport reopened, that we weren’t in the mindset to fly. Several instructors and workers at the airport did witness the crash.

2 thoughts on “Impossible Turn

  1. David,
    Thank you for sharing this. I remember you have stressed on number of engine-out emergency procedures and advised against such maneuver. We just cannot ignore the words of wisdom, even if they were expressed in gentle tone. Condolences to the fallen pilot and his family.

  2. Thank you. This is good advice for all pilots, and a great reminder to do more engine-out training and experiment (at altitude) to find out what turns are (im)possible to make in your plane and with your skills.

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