What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Stopping your engine in flight

N208ET said:
I had to reread my post, just to be sure I didn't ask a question about the validity of doing what I did, or if I thought it was safe or not. I asked whether or not there was any harm done to the engine, or will do to the engine from doing this, the only thing I could think of was shock cooling, a risk I thought of before executing this maneuver and took the appropriate precautions, both on shutdown of the engine and on the restart. But is there anything else, engine health wise, that I could be overlooking.

Look guys, as somebody pointed out, there is risk in what we do, like it or not. The day that I refuse to accept the fact that there is some risk behind flying, I quit flying, its that simple. I take more "calculated risks" when I am by myself. Both for education and to ready myself for real world emergencies. Notice I say, by myself. Cause that is the best time for things to go wrong, I want nobody else in the plane.

As a side note for anybody who chimed in who hasn't done this. This was absolutely a great learning lesson. There is a lot to think about before doing this. I learned a lot and have absolutely no regrets about doing it. I am not saying that everybody should run out and do this. But, I have recently started to run a mixture of mogas in my right tank. I tend to burn the mogas exclusively in cruise, sometimes to the point of running that tank dry. Like it or not, the best indicator that the tank is empty is when the engine stops running. Rather than avoid this situation, I have decided to embrace it, and find out what happens, in the most controlled way, without going crazy, I can think of. Is what I do for everybody, absolutely not.

And to whoever said they hope instinct takes over when their engine goes out. I really do hope your instinct just takes over and you do a great job if things hit the fan. Me, I guess I don't trust my instinct all that well, so I'm going to practice, practice, practice. That way when I'm taking young eagles, my nieces, friends, family, strangers, anybody flying, no matter what happens, I can always say "I did my best to be the best I could be, and I'll do my best to keep you safe and make it back." And that's all anybody can ask!

As a side note, Chuck Yeager must be a flippin idiot!

Randy

8A
Click to expand...


Randy, a simple straight answer to your original post and this clarified one, and that is you can't shock cool an engine that is already cool. Sure climb like an idiot with redline CHT's and dive, then do it hundreds of times that may not be the best, but from sub 380dF...the shock cooling is only when you spear into a lake.

Just like running a tank dry from time to time, so that you KNOW how much in flight usuable fuel you have is a flight safety matter, these emotive topics bring out all sorts of irrational fears.

Good work!
 
This is an important bit of information for those of you that fly fixed pitch props. I have had two engine outs that were NOT on purpose, both in my RV4 with a fixed pitch Warnke wood prop.
Our airplanes are slippery, and a fixed pitch prop still pulls while turning at idle power. You know this to be true because if you are even 5 knots too fast on approach the airplane seems to float forever. Also if you have the idle set a bit too high it will pull you when taxiing. These are indications that the prop is still pulling at idle and will still be moving your aircraft forward in the air at idle speeds. Thus when you lose your engine the prop is not pulling at idle like it is when you are practicing engine out scenarios, it will be an unusual approach.
The first time I lost my engine I was high, on final and a bit fast. For sure I thought that I would be off the far end of the 5000' runway. I landed, safely just past the numbers on the approach end!
You do not have to turn off your engine to prove this, I have done it for you. Expect NOT to go as far as you practice, thus plan to land farther down the runway if you lose your engine with a fixed pitch prop.
I have not done this test with my constant speed prop but I would not expect the same results as the prop is in fine pitch for landing and would not be pulling at idle as does a fixed pitch prop.
 
Last edited:
Above post is poor physics. At any reasonable airspeed, at idle power, the angle of attack along most of the prop is negative and the air drives the prop, which is why rpms are higher than when at rest. And why the prop is a source of drag, not thrust. And why the OP stopped it from turning. If the engine is running, then the drag is a little less. But not much. In typical Cessnas you cannot tell the difference beteen the engine windmilling at idle or no power.
 
Why don't those who advocate prop-stopped practice all the way to touchdown call their insurance companies, tell them how you are training to be safer, and ask for a rate reduction? Please report back their replies. These are the guys carrying the financial risk; if they say it's a good idea, then I'll change my mind.
 
Bob, with due respect, based on my experience, I disagree. A Cessna, with all that drag is not an RV, the comparison is totally irrelevant. The pitch on our fixed pitch props are much coarser then that of a Cessna. Perhaps my descriptive terminology is incorrect. But you will NOT goes as far with a stopped fixed pitch prop, at glide speed, as you will with one turning with engine power. I do agree that a windmilling prop with no power provides more drag then a stopped prop. A wood prop, with no power, will stop turning at about 100 knots, based on actual experience. Thus it is not producing much drag. However, under power, at idle, particularly a lower approach airspeeds, an idling fixed pitch prop is producing more thrust then drag. It is producing enough thrust at idle, vs a stopped prop, that you will land much shorter with the stopped prop. Try it.
The debate is about real experiences with using power for practice vs the engine off reality. My experience is that the reality is much different then the idling engine practice.
My experience at an airport with my first unplanned engine failure saved both my life and my aircraft, when I had to land in a field the second time the engine quit.
I am NOT advocating stopping your engine, I have not done it on purpose. But since it happened and I noted something I DID not expect I thought I would pass it along. If I am wrong and you land long you will likely survive. If however, you are wrong, and you come up short, it will not be pretty.
 
I stopped my engine on my Midget Mustang during my test phase. I had to get pretty slow to get the prop stopped and pretty fast to start it windmilling again. I was surprised to find on that plane that it had less of a sink rate with the prop windmilling than with it stopped. We learn the other way around, but I guess that all depends on the plane/prop combination. Knowing that it would glide further with the prop still windmilling was valuable information. Incidently, I am also a glider pilot and did this about 8,000' right over the airport so I was very comfortable with it.

On my Mustang 2 I have also done it, but I can not get the plane slow enough without stalling to stop the prop from windmilling.
 
Cut your power to idle on downwind abeam the numbers and learn to land using pitch, flaps and slips to arrive where you want instead of power, and you will have an edge on a real dead stick landing if it ever happens.
 
brian257 said:
I stopped my engine on my Midget Mustang during my test phase. I had to get pretty slow to get the prop stopped and pretty fast to start it windmilling again. I was surprised to find on that plane that it had less of a sink rate with the prop windmilling than with it stopped. We learn the other way around, but I guess that all depends on the plane/prop combination. Knowing that it would glide further with the prop still windmilling was valuable information. Incidently, I am also a glider pilot and did this about 8,000' right over the airport so I was very comfortable with it.

On my Mustang 2 I have also done it, but I can not get the plane slow enough without stalling to stop the prop from windmilling.
Click to expand...

... All you need to do to stop the prop is this. Pull throttle to idle, pull mixture to cut off lean, raise the nose and slow down then open the throttle to full open and the engine becomes a compressor and will stop dead in its tracks. Allan...:D
 
Stoping your engine in flight

One of the things my tailwheel instructor stressed to me was to practice engine outs. (Prop not turning). I had an engine out on take off and this practice at the least saved me some bent up aluminum. Thanks again Bruce (81D). A few things not mentioned in the threads is that your environment changes: there is zero noise and vibration. The controls have a different feel - slight but different. You do not want to experience these for the first time in an emergency. Yes practice engine outs!
 
I have had engine failure on take off and I'm here to tell you practcise your dead stick landings. I posted this on (stoping your engine in flight last thread). Remember dead stick means the motor is not running.
 
stopping engine

My partner and I, in our sixties, have always run 1 tank out of gas, engine dies, switch tanks, start up again in a 1959 Comanche 250 with a Lyc O-540. Partner doing it for 34 years and his father before that. No adverse affects. I think it's good real world training as long as you have outs; altitude and somewhere to set it down.

And you always know that the tank you're on is the only one with remaining fuel if things ever get tight :)
 
You must log in or register to reply here.
Back
Top