Engine out practice

With the few times it’s taken me a little while to get my hot fuel injected Conti started on the ramp, I think I’d rather not try this in case I needed to power back up right away. But that’s just me. I know the more practice and the more realistic the practice, the better prepared I’ll be. But I’m stuck suckling 100LL and haven’t tried weaning (gliders) yet.
 
I think you’ve got the basics of what you need to know...get the nose down. ;)

Beyond that, I’d suggest that you’re probably not going to be doing math in the cockpit during an engine failure to figure out how far you can go, so it’s going to be about picking an aiming point (whether it’s an actual touchdown target or a pattern target) and ensuring that it’s not moving up in your windshield in a stabilized glide...preferably moving down, since some conditions will probably change along the way. Those procedures and techniques won't change substantially whether the engine is idling or dead.
 
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Adam Weiss said:
Yes. I was solo.
I thought long and hard about it.
Glad I did it.
It really is a different animal from idling.
Now that I know the difference, I don’t think I would have a good feel for a real engine out by only practicing simulated.
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You should also practice with your wife along because best glide varies with weight, and the plane might handle differently with another soul on board.
 
Lindberg said:
You should also practice with your wife along because best glide varies with weight, and the plane might handle differently with another soul on board.
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If nothing else, it’s a great way to make sure she’s *not* along when you have an actual engine failure. :)
 
455 Bravo Uniform said:
Even though your glidieabilty distance increases with altitude, angularly it all looks the same from the cockpit. I’ve often thought about putting a mark on all my windows to mark my best glide max range.
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This is an common “Glider pilot’s trick”: use your extended hand and measure the width of several fingers down from the Horizon, that is how far you can glide. Eg depending on glide ratio for a competitive glider, it’s 3 fingers down from the horizon.
In my airplane (not high glide ratio) , it’s a full fist’s height below the horizon, that’s how far I can glide with engine-out.
A good “rule of thumb” to quickly get an idea what is too far to reach.


Side note: I wish everyone would get some glider training as part of their Pilot’s license. You learn a lot.
Pilots these days are too dependent on having a running engine all the time.
 
I tried this many years ago at altitude in a 125 hp Tripacer. I was amazed at how long it took for the prop to finally stop, and how diving to Vne (or thereabouts) wouldn't restart it. The slow windmill wind down was probably due to the metal prop inertia and moderate pitch.

To the OP - What type of prop?
 
What was done with the prop control during the engine off part of the flight?

On practice engine outs, engine at idle, I would pull the prop all the way back. Most single engines won't feather, but I could feel the difference in the glide with the prop control back.
 
Zeldman said:
What was done with the prop control during the engine off part of the flight?

On practice engine outs, engine at idle, I would pull the prop all the way back. Most single engines won't feather, but I could feel the difference in the glide with the prop control back.
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I have a fixed-pitch, 2-blade prop.
It did windmill for a while (20s maybe?) before it finally just stopped as airspeed dropped.
 
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Ryanb said:
Did you try this solo? I really wouldn’t be practicing engine outs with the engine totally stopped.
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Why kill 2 people?

Having the confidence in one's self and their abilities, is what was signed off on when you got your checkride successfully completed.

True, "there are old pilots and bold pilots, but few old, bold pilots."

But old pilots do bold things... Like land in a river with many souls aboard. Not something you do with a safety pilot, and something the sim said was the less safe option.

In order for a man to "know his limitations" he has to stretch himself.

Without the drag inducing windmilling prop, glide is actually more efficient. So it could be argued that "dead stick"/ stopped prop was actually safer than simulation.
 
Adam Weiss said:
I have a fixed-pitch, 2-blade prop.
It did feather for a while (20s maybe?) before it finally just stopped as airspeed dropped.
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What do you mean ‘feather’? A fixed pitch prop doesn’t feather.
 
Those of you who has been around here a while will remember Ron Levy. (don't get me wrong, he is not dead - to my knowledge - just not on the Board anymore. He was very much against shutting off the engine while in the air. His comment: Don't practice bleeding, either...

-Skip
 
Some of the confusion here comes from the assumption that the engine and prop will stop turning once you cut off the fuel and shut down the engine. That usually is not what happens in flight. The prop will windmill and turn the crankshaft, which takes a LOT of energy, increasing your rate of descent. By the time the airspeed drops to a point where the windmilling stops, you'll likely be on the ground.

With a constant speed prop, you can reduce the energy loss from windmilling by pulling the prop to "low RPM" (i.e. high pitch). This will allow you to glide farther. Not perfect, but better.

In a twin, you can feather the prop and stop the windmilling completely. That creates much less drag than from a spinning prop. That's about as good as it gets for a shut-down engine.

- Martin
 
I can't remember now, but doesn't the POH for both the 172 and PA-28 (the only planes I fly) have a glide distance table with fine print that says "windmilling prop"?
 
Martin Pauly said:
Some of the confusion here comes from the assumption that the engine and prop will stop turning once you cut off the fuel and shut down the engine. That usually is not what happens in flight. The prop will windmill and turn the crankshaft, which takes a LOT of energy, increasing your rate of descent. By the time the airspeed drops to a point where the windmilling stops, you'll likely be on the ground.

With a constant speed prop, you can reduce the energy loss from windmilling by pulling the prop to "low RPM" (i.e. high pitch). This will allow you to glide farther. Not perfect, but better.

In a twin, you can feather the prop and stop the windmilling completely. That creates much less drag than from a spinning prop. That's about as good as it gets for a shut-down engine.

- Martin
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OP here. I'm not refuting this, but that was not my experience.
I killed my engine, and the prop windmilled for 20s or so, then stopped as my airspeed dropped (I didn't nose over right away).
I think all this dialog is showing that until you try in your own plane, there's no way to know how it will behave.
 
Adam Weiss said:
OP here. I'm not refuting this, but that was not my experience.
I killed my engine, and the prop windmilled for 20s or so, then stopped as my airspeed dropped (I didn't nose over right away).
I think all this dialog is showing that until you try in your own plane, there's no way to know how it will behave.
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Right. You were there, and I'm not trying to argue with what you observed. What what the type of airplane, what engine, and how slow were you when the windmilling stopped?
The only time I've been able to stop a windmilling propeller was in a very low-powered motorglider, and even then I could only do it with the propeller brake it had for that exact purpose. The flip side is once the prop does stop windmilling, it takes a lot more speed to get it to move again.

- Martin
 
Martin Pauly said:
Right. You were there, and I'm not trying to argue with what you observed. What what the type of airplane, what engine, and how slow were you when the windmilling stopped?
The only time I've been able to stop a windmilling propeller was in a very low-powered motorglider, and even then I could only do it with the propeller brake it had for that exact purpose. The flip side is once the prop does stop windmilling, it takes a lot more speed to get it to move again.

- Martin
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Vans RV-9A with high compression 160HP O-320.
About 60kts when things stopped, then I nosed over back up to 80kts.
Best glide is 12:1 at 83kts.

I wasn't too concerned about getting it moving again, as this was a controlled outage.
I have starter that can get the prop moving if needed.
 
Wouldn't do it. Wouldn't be prudent.

images
 
By the way, this is why the assumption that people should be able to safely glide a plane beautifully into a field, or highway / parking lot without hitting anything and people walking away unscathed is a dubious one.

You did this experiment in a controlled environment, near an airport, really, you encountered an "engine failure" in the BEST, POSSIBLE, SCENARIO... and it worked! But there's a fair amount of disapproval from the board for attempting this

I wonder, how would most aviators fair losing their engine above the clouds getting vectors for an instrument approach into a busy Charlie.

Flying, especially dead stick flying, is NOT easy.
 
Also. gratuitous, "GA piston engines suck"

..the fact that "hot starting" an engine is such a disaster when a $500 piece of crap beater Hyundai with 300K miles on it will start whether it sat all winter for 6 months or is getting hot started in an August Phoenix parking lot is ridiculous

Yeah yeah, low volume, certification, simplicity, weight, etc., I get all that. But our engines are still, objectively speaking, giant piles of trash.
 
Tantalum said:
By the way, this is why the assumption that people should be able to safely glide a plane beautifully into a field, or highway / parking lot without hitting anything and people walking away unscathed is a dubious one.

You did this experiment in a controlled environment, near an airport, really, you encountered an "engine failure" in the BEST, POSSIBLE, SCENARIO... and it worked! But there's a fair amount of disapproval from the board for attempting this

I wonder, how would most aviators fair losing their engine above the clouds getting vectors for an instrument approach into a busy Charlie.

Flying, especially dead stick flying, is NOT easy.
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I agree.
And it's precisely why I wanted to practice.
I want to get to know my plane and how it behaves really well...all in an effort to be a better, safer pilot should an emergency arise.
 
Tantalum said:
Also. gratuitous, "GA piston engines suck"

..the fact that "hot starting" an engine is such a disaster when a $500 piece of crap beater Hyundai with 300K miles on it will start whether it sat all winter for 6 months or is getting hot started in an August Phoenix parking lot is ridiculous

Yeah yeah, low volume, certification, simplicity, weight, etc., I get all that. But our engines are still, objectively speaking, giant piles of trash.
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Not arguing, but even the hot start procedure is a non-event once you learn to do it.
My plane always fires on the first crank, hot or cold.
It didn't used to.
Only thing that changed was my experience.
 
Adam Weiss said:
I have a fixed-pitch, 2-blade prop.
It did windmill for a while (20s maybe?) before it finally just stopped as airspeed dropped.
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Metal (Sensenich presumably), or wood, composite, Catto, etc?

The mass of the prop is what would help keep it windmilling. From you're description, something <60Kts is where it stopped then, right?
 
Martin Pauly said:
Some of the confusion here comes from the assumption that the engine and prop will stop turning once you cut off the fuel and shut down the engine. That usually is not what happens in flight. The prop will windmill and turn the crankshaft, which takes a LOT of energy, increasing your rate of descent. By the time the airspeed drops to a point where the windmilling stops, you'll likely be on the ground.

With a constant speed prop, you can reduce the energy loss from windmilling by pulling the prop to "low RPM" (i.e. high pitch). This will allow you to glide farther. Not perfect, but better.

In a twin, you can feather the prop and stop the windmilling completely. That creates much less drag than from a spinning prop. That's about as good as it gets for a shut-down engine.

- Martin
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Are you saying that with the engine stopped but the plane moving that the prop blades will turn to “feather” into the wind? I wouldn’t think so. I think we need oil to be flowing for that to happen. No?
 
keen9 said:
mass of the prop is what would help keep it windmilling
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?

I'd assume more it's overall airfoil shape and engine compression resistance

There are also theories that windmilling is worse, as the assumption is the prior is still making "lift" vs being stalled
 
Adam Weiss said:
I agree.
And it's precisely why I wanted to practice.
I want to get to know my plane and how it behaves really well...all in an effort to be a better, safer pilot should an emergency arise.
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I think what you did is fine, it was done in a controlled way, and it's good to know how your machine (and you!) behave at the edges of, and potentially outside, its envelope

Some people judged my CFI for covering all but the altitude, compass, and ball, once on a night IMC flight back in IR training. Knowing you have a 6,000 hr cfi next to you is nice, but the threat of real spatial D becomes very real.. and the stress factor rises. It was fine, just *tiny* control inputs. But damn would I hate to have to do that in an actual emergency.
 
Adam Weiss said:
I have high compression (10:1) pistons to make 160hp in my O-320. I suspect that makes a difference.
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I am surprised as well, I have done it in 160hp 172's and Cherokee's.. and it usually takes taking it to near stall for a number of seconds for the prop to stop.
the RV-9 I would guess would have a bit more of a cruise prop compared to the 172 which I would think would make it even harder to stop the prop.


What Speed are you flying your emergency procedures at? Best glide or Normal Power off approach speed?
What Flap configuration?
How long does it take for the prop to stop once the engine is shut down?

Brian
 
Adam Weiss said:
I agree.
And it's precisely why I wanted to practice.
I want to get to know my plane and how it behaves really well...all in an effort to be a better, safer pilot should an emergency arise.
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That's all well and good, if you practice this and any other maneuver every month or so. But it doesn't take that long to forget, and if you did this and other similar things over and over, you are gonna hit that point where the chance of the training maneuver causing an issue is greater than the chance of the actual emergency. Some early spin training and one-engine-out twin training went this way.
(Of course, I also won't jump out of a perfectly good airplane with a parachute, but I've run 200 mph on a blown alcohol drag bike. We each choose our own risks.)
 
455 Bravo Uniform said:
Are you saying that with the engine stopped but the plane moving that the prop blades will turn to “feather” into the wind? I wouldn’t think so. I think we need oil to be flowing for that to happen. No?
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I don't know if I understood your question, but just to make sure we are on the same page for these terms:
  • Windmilling: means the propeller keeps turning after an engine stops producing power, where the propeller is driven by the relative wind. Any propeller/engine can do that. It's what typically happens after an engine fails.
  • Feathering: is a pilot-controlled action where the propeller blade angle changes such that the relative wind around the prop blades no longer creates any significant torque on the crankshaft. Used to stop windmilling, which in turn reduces drag significantly. Typically only available on multi-engine airplanes.
- Martin
 
Martin Pauly said:
I don't know if I understood your question, but just to make sure we are on the same page for these terms:
  • Windmilling: means the propeller keeps turning after an engine stops producing power, where the propeller is driven by the relative wind. Any propeller/engine can do that. It's what typically happens after an engine fails.
  • Feathering: is a pilot-controlled action where the propeller blade angle changes such that the relative wind around the prop blades no longer creates any significant torque on the crankshaft. Used to stop windmilling, which in turn reduces drag significantly. Typically only available on multi-engine airplanes.
- Martin
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Gotcha. We’re on the same page. Your comment confused me for typical SE piston aircraft: “With a constant speed prop, you can reduce the energy loss from windmilling by pulling the prop to "low RPM" (i.e. high pitch).” Your caveat that you meant multi clears it up.
 
How much can you really lower the rpms on a constant speed prop when the engine isn't running? Is there enough oomph to the governor to pump enough oil in to move the blades? Considering what happens when I pull mine to idle, I kinda doubt pulling the prop knob out is doing squat with the engine off.
 
455 Bravo Uniform said:
Your comment confused me for typical SE piston aircraft: “With a constant speed prop, you can reduce the energy loss from windmilling by pulling the prop to "low RPM" (i.e. high pitch).” Your caveat that you meant multi clears it up.
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No, I meant single engine. You can pull the prop on a single engine to "low RPM". It's not feathered, so it still windmills, but the glide performance is much better than in "high RPM". On a twin, you can pull it all the way to "feathered".

Salty said:
How much can you really lower the rpms on a constant speed prop when the engine isn't running? Is there enough oomph to the governor to pump enough oil in to move the blades? Considering what happens when I pull mine to idle, I kinda doubt pulling the prop knob out is doing squat with the engine off.
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Here is the thing: the engine IS running, it's just not making power. The oil pump and alternator continue to work as long as that crankshaft is spinning. Pulling the prop lever back makes a HUGE difference! When I did power-off landings for my commercial in the Bonanza, the RPM control gave me a lot of flexibility over the glide.

Try it out sometime: with the prop at "max RPM", bring the power to idle and establish a glide. Then pull the prop lever back - you can easily feel the acceleration!

- Martin
 
Martin Pauly said:
No, I meant single engine. You can pull the prop on a single engine to "low RPM". It's not feathered, so it still windmills, but the glide performance is much better than in "high RPM". On a twin, you can pull it all the way to "feathered".


Here is the thing: the engine IS running, it's just not making power. The oil pump and alternator continue to work as long as that crankshaft is spinning. Pulling the prop lever back makes a HUGE difference! When I did power-off landings for my commercial in the Bonanza, the RPM control gave me a lot of flexibility over the glide.

Try it out sometime: with the prop at "max RPM", bring the power to idle and establish a glide. Then pull the prop lever back - you can easily feel the acceleration!

- Martin
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I'll do it! I remain skeptical until I see for myself, but that's just my nature. ;)

I've done a zillion power offs and never used the prop. If it adds another tool to my toolbox, I'll owe you one!
 
Martin Pauly said:
Then pull the prop lever back - you can easily feel the acceleration!
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Oh for sure.. the inverse is also true and quite evident if you are at idle and go from the flight 2,200 RPM and push it all the way in to 2,700.. you'll feel the plane actively slow down
 
Adam Weiss said:
I'm considering making this something I practice regularly, and why I asked if other folks do it, and how they practice it.
The entire goal is to be a safer, more proficient pilot.
When I actually need to do it, I'd like it to be muscle memory, and not scrambling through checklists and second-guessing.
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The steps to establish restart can be done by muscle memory, but you don't need an exercise like I've outlined for that. Sit in your aircraft, and put your hands on everything you'd need to do in an engine out emergency. Do it in order, then do it again. The get out of your airplane, stretch your legs, take a whiz, get back in and do it a few more times. That's how you get muscle memory.

Personally, I think it an utterly useless exercise. The only real thing in your muscle memory bank is pushing on the yoke when you lose power so you don't stall. My CFI used to say when something bad happens, wind your watch. That is, take stock, and make intelligent actions calmly. Intelligent actions do not come by muscle memory. You're either going to have time to do it calmly or you're not going to have time to do it at all.

And getting a sick bird down from altitude and safely onto terra firma on a runway has nothing whatsoever to do with muscle memory. You can't practice for every eventuality, but if you do it a few times you'll have a good idea of what your airplane can do and what it can't. Do not shut off your engine. DO NOT SHUT OFF YOUR ENGINE. Nothing worse than making a simulated emergency into a real one. Someone blunders onto the runway while you're on short final and you'll be really happy you left the engine on. Yeah, an idling engine makes some power, but if you can really hit runways with the power off from altitude, you'll be able to easily compensate for the difference. Also, Foreflight has glide advisor, a really handy thing to let you know where you can get to and where you can't. Biggest killer in engine outs is guys trying to stretch the glide to get to the runway. You don't want to do that.
 
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