Lost engine training

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Tracey

Line Up and Wait
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tracey
If I were to lose an engine-- for real-- the prop would stop (as opposed to training), correct? So my question is-- would it be very different to glide a plane that does not have a moving prop?
 
If you lost it, the first thing you should do is look for it.

Okay, depending on the failure, the prop will either keep windmilling like it does when you just pull the throttle all the way back, or stop entirely.

If it keeps windmilling it will glide like what you are used to. If it stops, you'll glide a bit farther. The difference is not extreme.
 
Tracey said:
If I were to lose an engine-- for real-- the prop would stop (as opposed to training), correct? So my question is-- would it be very different to glide a plane that does not have a moving prop?
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Not always...depends on why it stopped, but generally it will stop which will glide a little better than a windmilling prop, but not as good as if it were feathered.
 
Fearless Tower said:
Not always...depends on why it stopped, but generally it will stop which will glide a little better than a windmilling prop, but not as good as if it were feathered.
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Eek, what does feathered mean?

And thank you... sounds like if you lost an engine, losing a prop would not be bad-- if it glides better!
 
Tracey said:
And thank you... sounds like if you lost an engine, losing a prop would not be bad-- if it glides better!
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Then you have two things to find!

You'll learn about feathered props if you ever fly a twin. Basically you can align the prop blades with the slipstream of the airplane to reduce the drag created by that prop when you are gliding. Most singles don't have the ability to feather fully... your fixed pitch 172 prop can't be adjusted period, so nothing to worry about there.
 
Tracey said:
Eek, what does feathered mean?

And thank you... sounds like if you lost an engine, losing a prop would not be bad-- if it glides better!
Click to expand...

Feathering a prop is turning the blades so that they are parallel with the airflow, minimizing their drag. The planes you fly during training don't have the capability to do that.
 
dell30rb said:
your fixed pitch 172 prop can't be adjusted period, so nothing to worry about there.
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Ok, one thing less to worry about then. Not going to complain about that!
 
gprellwitz said:
Feathering a prop is turning the blades so that they are parallel with the airflow, minimizing their drag. The planes you fly during training don't have the capability to do that.
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Got it, thank you!
 
Tracey said:
Eek, what does feathered mean?

And thank you... sounds like if you lost an engine, losing a prop would not be bad-- if it glides better!
Click to expand...

Here is a feathered prop:
48392517.jpg
 
Tracey said:
Eek, what does feathered mean?
Click to expand...

Something typically only found on multi-engine planes or turbo props - blade pitch changes when the engine is shut down to reduce drag.

Here is a feathered prop:
48392517.jpg
 
Hi, Tracy-

Barring a complete engine seize, the prop would windmill just like it does when you practice. I think there was a good article by Barry Schiff about attempting to stop the windmilling prop (by flying really slow) and thereby extending your glide considerably. Never done it, can't say. But if you ever have to to a forced landing in an airplane with a constant speed prop, pulling the prop control to full decrease will extend the glide a lot.

If you ever have to land an airplane for real after a failed engine, you'll never again be able to NOT think about where you might set down if it happens. At my home field, I have 3 or 4 places picked out if the engine ever quits shortly after take off. Hope I never need them.
 
j1b3h0 said:
If you ever have to land an airplane for real after a failed engine, you'll never again be able to NOT think about where you might set down if it happens. At my home field, I have 3 or 4 places picked out if the engine ever quits shortly after take off. Hope I never need them.
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I'm sure that's true, and I hope to never find out the hard way.
 
Tracey said:
Eek, what does feathered mean?

And thank you... sounds like if you lost an engine, losing a prop would not be bad-- if it glides better!
Click to expand...

Yep, if the engine dies with a fixed pitch/unfeathered prop, the spinning prop had the same drag as a flat plate the same diameter. Twins have props you can 'feather' streamlined with the airflow. Singles don't typically have this (there are a couple exceptions) so when the engine dies on them you hit the exploding prop bolts and get rid of it.
 
Tracey said:
If I were to lose an engine-- for real-- the prop would stop (as opposed to training), correct? So my question is-- would it be very different to glide a plane that does not have a moving prop?
Click to expand...

The prop in your 172 will keep spinning without a running engine until you get below about 60 knots. Although there are engine failure modes that could cause the engine to lock up and stop it at much greater airspeeds.
 
Tracey said:
If I were to lose an engine-- for real-- the prop would stop (as opposed to training), correct? So my question is-- would it be very different to glide a plane that does not have a moving prop?
Click to expand...

Under the most common failure mode of engines, loss of fuel flow, the prop will keep on spinning, but the drag will be higher than with the engine idling so you won't glide as well. If the prop is not moving your glide range improves. The higher you are the more advantage you get. There is a point in speed/altitude where it will no longer be to your advantage to stop the prop. If the engine fails catastrophically often the prop stops.
 
Tracey said:
Ba dum dum! And all this time I thought it was under the couch cushions.
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:rofl:

When you are done searching for the engine, there are lots of videos on youtube of actual engine failures - some unexpected and even some deliberate. (dead stick is a good term to search on) Even a dead stick takeoff / landing.

(I'm not going to attempt to debate the "actual engine shut down" thing.)
 
Barring a severe mechanical failure the prop will continue to spin just like it does in training. Contrary to what others will tell you it will glide pretty close to the same as it does with the engine at idle, but plan your approach so you don't come up short. Much better to overrun you landing area than to stall spin short of it.

Short answer is you training is very realistic of a real engine failure without a mechanical problem that mechanically stops the prop.

Brian
CFIIG/ASEL
 
jesse said:
The prop in your 172 will keep spinning without a running engine until you get below about 60 knots. Although there are engine failure modes that could cause the engine to lock up and stop it at much greater airspeeds.
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That is what I was missing - the speed....Never seen it in person, but I've seen a few videos of engines in singles actually shut down in flight a few times and they were all slow enough to stop the prop.
 
Thanks everyone... I appreciate the responses. I want to try to imagine what a real failed engine (ok, not lost... sheesh) might sound/feel like so that I can handle it and not freak out (it'll be a lot quieter, the prop may or may not stop... things like that I haven't trained for).

I really appreciate everyone here taking the time to explain things, thank you.
 
When I was in my first phase of training 20 years ago, I had an intense instructor. He would not sign you off for the checkride unless you spun first. Maybe that describes what he was like. He wasn't your conventional instructor.

One weekday when there was no one around the airport. We went very high among the downwind end of the runway and he cut the power. I don't mean he cut the engine to idle. He cut the engine OFF. I had to spiral down to the runway and land. With the engine COMPLETELY dead and the prop not turning. I could tell no difference in glide rate from when I had glided into fields for simulated emergency landings with the engine idling.
 
Where is that list of funny airplane squawks with the mechanics responses? You know the one I mean.
 
Tracey said:
Thanks everyone... I appreciate the responses. I want to try to imagine what a real failed engine (ok, not lost... sheesh) might sound/feel like so that I can handle it and not freak out (it'll be a lot quieter, the prop may or may not stop... things like that I haven't trained for).

I really appreciate everyone here taking the time to explain things, thank you.
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It's been my experience that it is very difficult to stop the prop....it takes a nose-up attitude far in excess of what you see in power-on stall practice, and when it is time to start the engine again (without the starter) you have to dive pretty drastically to get enough airspeed to turn the prop against engine compression.

Bob Gardner
 
MBDiagMan said:
When I was in my first phase of training 20 years ago, I had an intense instructor. He would not sign you off for the checkride unless you spun first. Maybe that describes what he was like. He wasn't your conventional instructor.

One weekday when there was no one around the airport. We went very high among the downwind end of the runway and he cut the power. I don't mean he cut the engine to idle. He cut the engine OFF. I had to spiral down to the runway and land. With the engine COMPLETELY dead and the prop not turning. I could tell no difference in glide rate from when I had glided into fields for simulated emergency landings with the engine idling.
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That surprises me, doc. I've killed engines on students hundreds of times and the prop never stopped.

Bob Gardner
 
bobmrg said:
That surprises me, doc. I've killed engines on students hundreds of times and the prop never stopped.

Bob Gardner
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Doesn't really require that excessive nose up. As Jesse mentioned, speed is the most important, so maybe it just depends on the plane.

Here is a video a friend of mine posted where they perform a deadstick landing in a 150. Doesn't take a whole lot to stop the prop, just slight nose up:

http://www.youtube.com/watch?v=BhbvZ-3TX4g
 
Actually, to take advantage of stopping the prop, like you KNOW you're out of fuel now, is to immediately pull up 3g for a steep climb until the prop stops then push over for best glide. Bleeding speed off slowly down to prop stopping will hold you sinking below LD Max for too long stopping the prop than you can make up for unless you are really high when it happens.
 
bobmrg said:
That surprises me, doc. I've killed engines on students hundreds of times and the prop never stopped.

Bob Gardner
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It's been twenty years so the details are a bit cloudy in my memory. I don't remember if we pitched up or what we did. But I remember how eerie it was in the silence.
 
I have had a couple of engine failures during my life in aviation. I have never suffered an engine failure in a turbine. I had a GE CF-34 on a Challenger blow turbine blades out the back. All that we saw was a slight rise in engine vibrations. It still ran just fine for an additional 3 hours. We were talking to the GE reps on the flitephone while trying to trouble shoot the issue. The engine then went in for overhaul after that flight. We diverted into the airport that the engine factory is located at in Kansas.

The full engine failures have always been in recips.

The first was in a Piper Warrior. It was a clogged fuel line. At night, followed by a landing on a runway. Thankfully I was flying at 10,500 at the time. I flew the glide speed. The prop did stop half way down to the runway.

The second was in a Piper Seneca. It was a broken crank shaft. It was one of the ones in the effected bad batch that Continental put in the TSIO-360 engine. The prop stopped about 10 seconds after the vibrations started.

The third was in a Piper Dakota that had just gone under major servicing on a pre-purchase and annual inspection. The mechanics had gone back in after the airplane was inspected and test flown to make a minor adjustment. They had to remove an oil line. They forgot to properly tighten the hose back on. They also forgot to let me know that they had done additional work to the airplane after the maintenance inspection. I got about 15 miles from the airport when the oil light came on and all oil pressure was lost. I was able to get back to the airport. I would reduce power each time the engine felt like it was going to seize. The engine actually failed and seized when I was about a mile out on final. Needless to stay the prop stopped.

The forth was on a Cessna 421. I had a low oil pressure indication on the left engine on departure. I ran the engine at idle for about 5 2 minutes to monitor the oil pressure. After 2 minutes I did a precautionary feather and shutdown. Then a single engine ILS approach and landing back into the airport. The result of the oil pressure loss was the engine was coming apart. There was lots of metal in the oil filter. Previous oil analysis had normal indications. RAM replaced the engine at no charge.

I would much rather just have the prop stopped when having to make a single engine landing. Its one less thing to have to be thinking about on the way down. Also with each situation I was always able to get the airplane to an airport. I always have immediately declared an emergency and had the fire trucks available when I arrived.
 
Fearless Tower said:
Doesn't really require that excessive nose up. As Jesse mentioned, speed is the most important, so maybe it just depends on the plane.

Here is a video a friend of mine posted where they perform a deadstick landing in a 150. Doesn't take a whole lot to stop the prop, just slight nose up:

http://www.youtube.com/watch?v=BhbvZ-3TX4g
Click to expand...


I enjoyed the video. I thought he was way high, then I saw the displaced threshold.
 
MBDiagMan said:
It's been twenty years so the details are a bit cloudy in my memory. I don't remember if we pitched up or what we did. But I remember how eerie it was in the silence.
Click to expand...

My experience was in a Cessna 120...not too much different from your 140, and it was wa-a-a-a-y more than 20 years ago! :D

Bob
 
Tracey,

A student pilot yesterday texted me about these videos. Here are the ones concerning engine out training.

Engine out, runway remaining:





Engine out, no runway remaining:




Engine out at altitude:




Hope this helps.


Blue Skies,

Kimberly
 
Thanks for the links Kim! I will take a look....
 
There's two primary errors in an engine out that will bite people: Too much energy and the g forces at impact are unsurvivable; too little energy and they stall trying to stretch their glide. Your primary concern is maintaining a path to a spot that will give you at least 200' to absorb energy before hitting something within that envelope range of energy. If you are in a retract plane and length is questionable, don't worry about the gear. Planes take amazingly little damage from a controlled belly in. As long as you hit whatever you're gonna hit at the end at 30 or less, you're likely gonna be ok. If you hit at less than 20 you're likely gonna walk away. Emergency landings are all about maintaining controlled deceleration; ideally below 8g but critical to lethality, below 50g. Remember, as soon as things go south, the insurance company owns the plane and the tin is there to save your skin. Planes are actually pretty well designed to save your life as long as you keep them in control, wings level, straight ahead and with a minimum angle of intercept with the ground. In a really desperate emergency short field landing, say a small clearing in a largely inhospitable terrain, you can let it get really slow on final with the horn blaring and steep as hell over the tall trees with a 1000fpm descent. You won't be able to flare at the bottom, but the gear and the airframe will absorb enough of the energy that you have a chance for survival, it'll also absorb enough energy that by the time you make it to the big rocks or timber at the end, you're slow enough to bounce. The trick is to spread your inertia reduction over as much time/many events as possible.
 
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