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  #11  
Old 07-02-2013, 08:07 AM
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airguy airguy is offline
 
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Quote:
Originally Posted by Nihon_Ni View Post
A windmilling prop produces more drag than a stopped one does, even with the engine at idle. If you have the skills to land the airplane with a windmilling prop, then you can apply those same skills to land if the engine ever quits for real.
Except that, as you pointed out, the drag is very different. If you've practiced engine-outs a hundred times with a windmilling prop, and have an engine seize up on you one day in flight and try that very same approach, you'll have too much energy as you approach the field because you have less drag. There is no one-size-fits-all solution here, other than being fully mentally-engaged in what you're doing.
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  #12  
Old 07-02-2013, 08:18 AM
RV Wannabe RV Wannabe is offline
 
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Originally Posted by Bob Axsom View Post
The greatest value in this thread is that the tester verified that some RV will glide and that he was unable to achieve a restart even though he tried. My goodness we have pilots that are learning to fly in the RVs they built and others fretting over flap use in landing. Even implying that all REAL PILOTS should shut down their engine and attempt a dead stick landing as good risk management is incredible. If they took this seriously we would have RV's down all over the place. If you want to do it, that is your business but to suggest that it is something that everyone should do is irresponsible I believe.

Bob Axsom
Yet you believe it is acceptable to plot a race course, or even fly it over glider, or skydiving operations without the operation knowing about it? Ripping across the airspace as fast as you can go not knowing if they know you are there?

Obviously there are many different folks on here with differing ideas of what is acceptable.

As to answering the OP's question. As long as you accept that not getting it restarted, or someone cutting you off in the pattern could result in an extremely embarrassing (at the very least) outcome (to you and or the poor schmuck that you would possibly cut off in the pattern). To me the risk you pose on the other guy makes it not the best of plans.

I used to train twin turboprop students with one engine feathered landings. I don't do that anymore because of incident reports.

Mark

Last edited by RV Wannabe : 07-02-2013 at 08:50 AM.
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  #13  
Old 07-02-2013, 08:32 AM
David-aviator David-aviator is offline
 
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Dealing with an engine failure is a mental issue of dealing with the event. If practicing it serves to prepare for it, have at it, but do so with the knowledge it is not risk free.

When it happens for real, it won't be at a time or place of your choosing. A pre-planned, previously practiced response, is not always be the best response. The circumstances of the failure are not predictable and as such, one needs to hang a bit loose with regard to reacting to the event. It really depends on the airplane and the operation. An engine failure on or immediately after take off requires a different response than one at altitude.

I've shut one down at 10,500' due to a prop failure and another simply quit cold at about 1000' agl. As stated above, both were a surprise. I had never practiced a SEL shut down so it was a first experience. Practicing it would not have mattered, IMHO, you deal with the matter as circumstances dictate. The objective is to land and walk away from it. Bob Hoover once said, fly the airplane as far as possible into the crash - that's what it is all about - do not stall. You do not have to practice not-stalling-an airplane, just fly it normally, push the nose over and keep it flying.

The FAA does not require or recommend training with an engine shut down for good reason, the risk involved is not worth it. Same applies to shutting down an engine with a twin. Too many people have died doing it.

The message here is do not minimize the risk. It is real.

This business of diving to start the engine seems an exercise of going no where but down. Why not use the starter?
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  #14  
Old 07-02-2013, 08:59 AM
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Quote:
Originally Posted by David-aviator View Post
This business of diving to start the engine seems an exercise of going no where but down. Why not use the starter?
Well, it's possible the starter is non-functional, so the question is not entirely academic. In many cases though, the answer is "Because I can!" I'd be lying if I said I didn't enjoy pointing the nose down 30 degrees to build the airspeed and spin it up.
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Last edited by airguy : 07-02-2013 at 09:03 AM.
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  #15  
Old 07-02-2013, 09:12 AM
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MauiLvrs MauiLvrs is offline
 
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Originally Posted by Low Pass View Post
As for shock cooling, I wouldn't and don't worry (-320, 360, 540 series). What happens when you fly though rain?
That's not what Lycoming says ... but what do they know... they only designed and built it
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  #16  
Old 07-02-2013, 09:15 AM
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John Clark John Clark is offline
 
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Quote:
Originally Posted by David-aviator View Post
When it happens for real, it won't be at a time or place of your choosing. A pre-planned, previously practiced response, is not always be the best response. The circumstances of the failure are not predictable and as such, one needs to hang a bit loose with regard to reacting to the event. It really depends on the airplane and the operation. An engine failure on or immediately after take off requires a different response than one at altitude.
Thanks David, you saved me a lot of typing. In the real world, training never seems to cover what really happened. Too many possible combinations.

A couple of thoughts on stopping engines in flight. First, it is a big, avoidable risk. If you are intent on exploring that part of the envelope I suggest working out some "zero thrust" power settings, just enough to negate the prop drag but not enought to extend the glide. It will take a little time to find the power settings in a particular aircraft. I would suggest having someone else (CFI) handling the power setting while you fly the airplane. This way when the plan doesn't work out, you don't have to explain it at the hearing.

John Clark ATP, CFI
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  #17  
Old 07-02-2013, 10:34 AM
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aarvig aarvig is offline
 
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Quote:
Originally Posted by Pat Stewart View Post
To each his own, not my idea of good risk management.
Agreed...I don't think the idea of shutting off your engine in flight is a safe way to practice engine outs. Why stop a perfectly good running engine and possibly create a problem where there never was one?
I think shock cooling is the least of your worries with this practice. There are more stats of pilots crashing/having incidents with this practice than there is of any benefit one may perceive it provides. I practice engine outs by reducing power to idle. Is it the same as an engine out...no. Is it close enough...yes. Is it safer than shutting down a perfectly good engine in flight...yes. Not trying to be rude here. I am curious as to what your rationale for this practice is?
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  #18  
Old 07-02-2013, 10:48 AM
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LettersFromFlyoverCountry LettersFromFlyoverCountry is offline
 
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I think the value of practicing dead stick landings and engine out is imprinting in your mind what it is you want to do, possibly more so than how your plane is going to act when it actually does go toes up.

My guess -- and I hope it remains a guess forever -- is that an engine out is an entirely different beast when you intentionally make it so as opposed to when you're cruising along and all of a sudden it gets really quiet. I'm not sure you can ever really practice that and I'm not entirely sure that fact makes flying the plane the same in that situation. I'm not sure it doesn't either. Like i said, it's just a guess.

But the procedures certainly are the same and if I had to assign a priority on preparing for the worst, getting to the point where the brain automatically takes over in those first few minutes would be -- and is -- job #1.

I'm certainly not going to judge anyone who approaches it differently.

Good luck.
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  #19  
Old 07-02-2013, 11:26 AM
Sig600 Sig600 is offline
 
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Quote:
Originally Posted by MauiLvrs View Post
That's not what Lycoming says ... but what do they know... they only designed and built it

This. Just read an article about this yesterday, cooling of 50-60 degrees per minute is classified as shock cooling and can do damage to the pistons and rings (assuming the motor is turning). If the motor is stopped though?
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  #20  
Old 07-02-2013, 12:20 PM
David Paule David Paule is offline
 
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Shock cooling can lead to cracked cylinders. The damage is cumulative or cyclic in nature.

Out here, the glider tow pilots use special descent techniques to avoid that, or at least did in the '80s. I had the good fortune to get a brief bit of instruction from a CFI who was an active tow pilot. In a 180 hp Super Cub, the procedure was to keep the power at cruise, roll 90 degrees, use elevator to manage airspeed. When at the desired altitude, roll out and make a normal approach.

Dave
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