Engine failure turn back.

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bmcj

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A steep turn unpowered with no reserve airspeed requires a dive.
It seems to me that a hammerhead turn might be considered a steep turn with no reserve airspeed (at the top of the maneuver), and it starts with a zoom climb. 😉
 

BJC

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A steep turn unpowered with no reserve airspeed requires a dive.
Sorry, but you do not understand the issue.
Bill’s statement is accurate; a steep turn unpowered with no reserve airspeed requires a dive. The only element that potentially could be debated is the definition of a dive.
All engine failures require you to get the nose down immediately.
Not true as a blanket statement; it all depends on the situation before the engine failure and the objectives following the engine failure.


BJC
 

edwisch

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Boy, is there a lot of pseudo science, generalizations and just plain errors in this discussion!

* The appropriate math to discuss “optimal” flight path is the calculus of variations, first invented in the late 1700s. Once you understand calculus of variations and have solved a few problems with it and understand intuitively what optimum solutions look like and what they do not, then discussions of things like speed for minimum sink at a given bank angle become, from that viewpoint, over-simplified to the point of irrelevance. Yes, I studied math as an undergraduate and optimal control theory in grad school.
* There’s also the human factors element. Has anybody on this group actually tried holding precise airspeed, power off at, say Vy, in a precise 45° bank? Go try it and report back… especially if you have to chop power at a Vy+10 climb and have to get right to that bank angle and speed.
* Another point never discussed is how sensitive “optimal” turns are. How much “performance” do you lose if you’re 5 knots fast or slow, or if you’re banked 10° too much or too little?
* Similarly, if you’re focused too much on holding precise speed and bank angle, what does that do to your situational awareness, such as judging the wind or considering other options?
* There’s also the question of whether getting back to the runway is really what you want. If there’s a stiff breeze and even a medium length runway, your preferred technique might let you touch down on the runway but roll off the other end at a goodly clip… if you don’t run into the next fellow taking off.
* One poster wrote that after engine failure, you must immediately push the nose over to Vy. Uh, no. If I’m at Vy + 25, climbing 1200 ‘/minute, as I usually do for engine cooling or to see over the nose to avoid buzzards, maybe I could trade some of that extra energy for extra altitude and more options.
* One point that is occasionally brought up is that everybody has their own version of where an “impossible turn” starts, what the weather is, etc. The comparisons then are like apples to oranges to orangutans, etc.

The best arrows to have in your quiver:
- Be able to confidently and safely maneuver your plane at low speeds, power off. Better to fly into the ground power off under control than not.
- Have a plan for each takeoff and what you’ll do in case of engine problems here and there. You probably won’t be able to plan on every eventuality, so figure what risks you’re willing to take. After all, if you were totally risk averse, you wouldn’t fly.
- If you own the plane, be carefully attuned to the engine, the handling, and every little cue. Often there are little cues before big problems.
- IMSAFE is a little corny, but if one of those elements is weak on any given day, your flying skills are likely to be degraded… not to mention keeping up your proficiency.
 
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BBerson

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It seems to me that a hammerhead turn might be considered a steep turn with no reserve airspeed (at the top of the maneuver), and it starts with a zoom climb. 😉
Well, the hammerhead is also called stall turn but it really is not a turn but just a yaw at zero g.
Still need a dive for recovery
 

F3A-1

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Everyone is envisioning the scenario that suits them. You can practice all you want and have the engine go rough or quit at any unexpected time. NO TEXBOOK can give you the answer. You and you alone must make the choice based on your ability in the aircraft you are flying and the circumstances you are facing. The internet cannot predetermine any outcome, only the pilot and physics of the exact event can.
 

jedi

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Everyone is envisioning the scenario that suits them. You can practice all you want and have the engine go rough or quit at any unexpected time. NO TEXBOOK can give you the answer. You and you alone must make the choice based on your ability in the aircraft you are flying and the circumstances you are facing. The internet cannot predetermine any outcome, only the pilot and physics of the exact event can.
There is a rule of thumb though that any student pilot or higher should know. If you haven't turned crosswind the plan is to land straight ahead until the PIC determins that a turn is possible and a better course of action.
 

tallank

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A steep turn unpowered with no reserve airspeed requires a dive.
Why are you flying at a no reserve airspeed? That is a theme I have seen in a few comments. You should not be flying at VX, you will eventually die doing this. Best glide speed plus a little.
 

BBerson

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By the way, you said "vertical" dive as in 90 degree straight down.
I said "if":
[If a steep turn ends up in a vertical dive there is a minimum required altitude to perform the dive recovery before hitting the ground. Full back stick won't help.]
Any sort of dive requires more altitude to level and flare and must be considered if maneuvering (turning) close to the unforgiving ground. The simple act of turning confuses and kills plenty of pilots. Read Stick and Rudder for advanced comment about how turning kills pilots.
 

tallank

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I said "if":
[If a steep turn ends up in a vertical dive there is a minimum required altitude to perform the dive recovery before hitting the ground. Full back stick won't help.]
Any sort of dive requires more altitude to level and flare and must be considered if maneuvering (turning) close to the unforgiving ground. The simple act of turning confuses and kills plenty of pilots. Read Stick and Rudder for advanced comment about how turning kills pilots.
I am in agreement with everything you are saying because it is true IF you fly at minimum airspeed. I said if you fly at minimum reserve air speed, you will die. So don't do that.
 

BBerson

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I am in agreement with everything you are saying because it is true IF you fly at minimum airspeed. I said if you fly at minimum reserve air speed, you will die. So don't do that.
Right.
The problem is minimum reserve airspeed can go up instantly with the 60-70° bank angle. The airspeed indicator lags. So only a qualified pilot should attempt dead stick steep turns near the ground.
 

tallank

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Right.
The problem is minimum reserve airspeed can go up instantly with the 60-70° bank angle. The airspeed indicator lags. So only a qualified pilot should attempt dead stick steep turns near the ground.
The airspeed indicator does not lag, the rate of climb instrument has a two minute time constant. Where are you coming up with all of these ideas? Try doing a 50+ degree bank and hold a constant airspeed.
 

tallank

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Right.
The problem is minimum reserve airspeed can go up instantly with the 60-70° bank angle. The airspeed indicator lags. So only a qualified pilot should attempt dead stick steep turns near the ground.
Please get some advance flying instruction. There is just too much that you have misconceptions of.
 

mcrae0104

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Is BB wrong somhow
No, Bill is correct. There can be minute lag when airspeed is changing--as with any pitot-static instrument--depending on the design of the system. Finding out just how much lag your system has while executing a power-off steep turn at low altitude doesn't sound like anything I'd care to try. In normal maneuvers you probably won't ever perceive it.
 

Pilot-34

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No, Bill is correct. There can be minute lag when airspeed is changing--as with any pitot-static instrument--depending on the design of the system. Finding out just how much lag your system has while executing a power-off steep turn at low altitude doesn't sound like anything I'd care to try. In normal maneuvers you probably won't ever perceive it.
We are talking a 2 second lag at a critical time
Throw in a few seconds lag for your scan and quickly changing bank angle during a busy time and
 

tallank

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Two minutes? Looks like a typo to me!!

(I've never had a typo... )
Not a typo. This is why sailplanes do not use a rate of climb instrument. They us a variometer. Same thing but with a time constant of a second or two. Next time you take off watch the rate of climb. It takes minutes before it reaches its real number.
 
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