Teaching power off 180's

I was flabbergasted when I found out that the power off 180 accuracy landing was a commercial maneuver. I had been doing them since before I soloed. Anyway, from the back seat, I watched a CFI candidate who clearly had no concept of energy management that just turned for the numbers as soon as he pulled the power, and missed the aiming point horribly. I know you can learn to do a downwind/base/final that's a constant turn, but that's probably not what you've been doing your entire flying career. Fly a downwind, base, and final just like normal, but you may have to turn earlier because you don't have the power.

The aiming point moving up or down works while you're on base. If it's moving up in the windshield, you're short: turn more direct to the point, reduce drag if you can. If it's moving down, you're high: increase drag, widen your turn.
 
You think the F-35 will?

Yes, I would have to imagine that it would. That said, taking a jet to high/low key on the USN/USMC side is a precautionary maneuver in nature. You executed it by locking the throttle at ~80-85% (can't remember which), which basically would minimize the wear on a motor that was eating itself up, and the profile you flew (somewhat like a space shuttle approach) kept your energy at a level that you would be able to trade airspeed for altitude and eject safely if the motor died. It was not meant to set you up for a dead-stick landing (at least one that you would likely walk away from). Maybe mhcasey can comment on the Viper pattern, they might have a different outlook on it given the sweet youtube video we have all seen.
 
No need to really have set points like that, since GA planes don't have the horrendous descent rates that fighters do, where meeting certain specific parameters at specific points, is paramount.


The T-34 uses high/low keys and it has a 12:1 glide ratio. I always wondered myself once I started Navy flight training, why the civilian side never taught high and low key. I have no idea about the T-6 though.
 
Reading and following this post has proved mind boggling. Among other things, I find it extraordinary how many are in agreement with "there is no target speed" or "speed variations are acceptable." Especially when some of those who agree have gone on to point out the importance of an unchanging glide path.

The way I see it, when teaching a maneuver it is imperative we understand it's purpose. I would say the purpose here is to practice the final phase of a forced landing. While simultaneously working to improve glide judgement skills.

Given that, a few things need to be mentioned:

  1. Judgement of glide path is the single most difficult visual task. So take your time.
  2. Glide path varies with changes in speed (ground speed).
  3. Impact at minimum speed maximizes the chance of survivability. Impact forces (Kinetic Energy) increase with velocity squared.
  4. Consistency with configuration and flying habits build consistent results and simpler judgements. (More on this later)
  5. And finally, treat it like any other emergency engine out practice: Fly best glide speed. More here in a moment also.


Expanding on number 4, it can be helpful to cover human physiology related to this task. That is, how good habits are formed through practiced, well understood, technique. This is why we learn and practice three steps to handling an engine failure. Why multi engine pilots learn an engine securing flow. And used throughout our lives outside of aviation: cooking food, washing dishes, your morning routine, etc. In other words, practicing your technique evolves into your habit; your very own procedure.

With that said, develop your own technique for each aircraft, one you've planned ahead for and hopefully have thoughtful reasoning behind. Then practice it till it becomes a habit. For me, single engine is fly best glide, flaps 10 abeam the landing site, and fly. Configuration changes, including gear, are used as needed to control descent. All landings are minimum speed full dirty, to simulate stuffing it into a 50 foot field.



Expanding number 5, flying best glide serves two purposes. The most important, giving a consistent starting point. The place of impact at best glide AOA (speed corrected for weight), no wind, will be a certain number of degrees below the horizon. Learn that point as it will not change and gives a ballpark for judging how winds and configuration changes will effect your point of impact.

The second purpose for fly best glide in this maneuver is simplicity. It's often joked that you would never lose an engine at the optimal place like this. This is true, however, a large portion of time is spent at altitudes greater than 2,000 feet. If you lose an engine there - ABC. Fly best glide, get to a landing spot, circle that spot, and checklists as able. Time your circling so you end abeam the landing point at or near pattern altitude, and execute your power off 180. Fly best glide because, with an engine failure at any altitude greater than critical, you will probably already be entering this maneuver at best glide to begin with. Why change it?



Point is, spend time learning to judge glide path. To do that best, you need to minimize all the extra changes: airspeed, configuration, crotch itch, etc. These are all added distraction, keep it simple, doing as little as possible, so you can see as much as possible.

Just my not so humble .02, as usual. :)
 
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