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Engine Out on Climb out - a test

J

jveatch

Member
I know there has been much debate over the issue of whether to return to the departure airport or to continue ahead when faced with an engine out during the initial climb out. We all have probably pulled the power at several thousand feet and measured how much altitude we lost in a 360 deg turn. I decided to do a more realistic test in our RV-12 and actually pull the power when departing the airport.

So in the early evening on October 3rd, with no traffic in the pattern, I departed the 6000 ft long runway 20 at KPWT, the Bremerton National Airport (440 MSL). Winds were 10 kts from the south. At various altitudes I pulled the power, then initiated a left 270? turn followed by a right 90? turn to attempt a landing (RWY 02). My bank angle visually seemed to be 45?, which I found to be surprisingly comfortable. I initiated this maneuver when climbing at 75 kts, first at 1200 ft MSL, then the next time at 1000 MSL, then 900 MSL, then 800 MSL, and finally 800 MSL with a 3 second delay before initiating the first turn.

All were successful ... in fact the only one that was marginal was the first one at 1200 ft because I was too high to land by the time I was back over the runway -- it would have been better in that case to have treated the approach as a downwind to RWY 20.

In each case (except the 1200 ft one) I would easily have been able to land before running out of runway with the 10 kt landing tailwind.

I concluded there would be no problem landing the RV-12 with the engine quitting when only 360 ft above the runway.

Amazing, huh. Well, I was surprised anyway. I am confident that in our RV-12 one could do a successful "return to the runway" any time after passing 300 ft AGL.
 
The impossible turn.

Please allow more altitude for a safety margin; to compensate for density altitude, wind, gross weight and "fear factor". During 46 years of flying light piston aircraft I have witnessed three unsuccessful attempts that resulted in smoking holes in the ground.
Oregon RV6
 
I'd also suggest - at altitude, over the airport - test the glide ratio with the engine at idle, and again with the engine actually off. Depending on where your idle rpm is set, you may see a considerable difference.
 
BobTurner said:
I'd also suggest - at altitude, over the airport - test the glide ratio with the engine at idle, and again with the engine actually off. Depending on where your idle rpm is set, you may see a considerable difference.
Click to expand...

If the glide ratio is different with the engine actually off verses at idle, then that would certainly change the conclusion about 360 ft being sufficient. How much of a difference would you expect that there is? If I do a 360 deg turn with the engine-off I'll go back to a much higher altitude (and over the airport), not the close-to-the-ground like this was.
 
jveatch said:
If the glide ratio is different with the engine actually off verses at idle, then that would certainly change the conclusion about 360 ft being sufficient. How much of a difference would you expect that there is? If I do a 360 deg turn with the engine-off I'll go back to a much higher altitude (and over the airport), not the close-to-the-ground like this was.
Click to expand...

As already mentioned.... Depending on what your idle speed is, the difference could be significant.
 
Difference

...and not particularly negative: I also fly TMG's that significantly soar better with an off engine the with the milling one on idle...
 
You say "pulled the power".
That must mean to idle...there is a difference, with engine failure you will experience more drag and more personal pucker.
Don't count on it working, statistics say landing straight ahead is better.
 
Hey John J (jveatch)! Looks like you took a lot of flack over the posts on your idling engine, and testing returns to your airport. I think your test were very informative. I agree that there are variables, but it was still fantastic info. Thanks for posting it........Tom
 
todehnal said:
Hey John J (jveatch)! Looks like you took a lot of flack over the posts on your idling engine, and testing returns to your airport. I think your test were very informative. I agree that there are variables, but it was still fantastic info. Thanks for posting it........Tom
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I concur. Nice job. You are comfortable with the maneuver and have practiced it. Some people are comfortable with no turns from 1,000ft. Reminds me of talking to another (older) student pilot back when I was training.. he was talking about making no greater bank than 15 degrees when in the pattern.. guess his instructor told him that because he couldn't fly worth a xxxx. Who knows. :D
 
Hey John J Looks like you took a lot of flack over the posts on your idling engine, and testing returns to your airport. I think your test were very informative. I agree that there are variables, but it was still fantastic info. Thanks for posting it........Tom
Click to expand...

I don't see that anyone has given him flack about his tests....
Just pointing out that the information being provided does not show what would happen if the engine actually quit.
In my opinion, that is rather important. For him, and for anyone that might take his info and use it in an actual emergency situation.
 
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OK, so what is the conclusion here? His test (at idle) indicated 360 feet of altitude was enough to make it back to the runway. Is it acceptable to say he should double that for the real world scenario, say 700 feet?

BTW My flight instructor suggested to me that "straight ahead" means up to +/- 90 degrees so as to not hit anything "straight ahead". :D

Bevan
 
Bevan said:
OK, so what is the conclusion here? His test (at idle) indicated 360 feet of altitude was enough to make it back to the runway. Is it acceptable to say he should double that for the real world scenario, say 700 feet?

BTW My flight instructor suggested to me that "straight ahead" means up to +/- 90 degrees so as to not hit anything "straight ahead". :D

Bevan
Click to expand...

Can't answer the question with the information that has been provided.

As already mentioned, with the course prop pitch that we use on the RV-12, idle speed can have a significant effect (and the OP has never mentioned what his idle speed is set at)
 
Suggestion

As a test.....

Climb up above your home field (no traffic day) to 3000 AGL and pull the engine to idle and establish best glide speed. Note the rate of descent. Add power and climb back up to 3000 AGL and slow the aircraft to near stall and shut off engine. The prop will begin to windmill at 65kts. Establish same speed as before and note rate of descent. Restart engine and enjoy rest of flight.

Report back to this forum your findings.
 
Return

As I have posted before Sunrise Aviation at John Wayne Airport teaches turn back to pre solo students. VERY hostile environment around this airport and despite the long primary runway many of the GA operations are on the shorter runway. Video of the owner of Sunrise conducting tests in a 172 at a strip inland from John Wayne.
 
Prop

Real world experience related by a pilot that had the prop come off a Pitts S2B due to crank flange failure. There was no damage to the cowl or airplane and the glide was so much better without the prop that he almost overshot a 4000' runway. This was NOT a turnback maneuver. The late August Raspet conducted tests with prop removed and cowl sealed, with the airplane towed to altitude behind a 450 Stearman. CAFE foundation also did this. There is a video somewhere of a dead stick aerobatic routine in a Pitts S1S including landing with the prop stopped.
And of course Bob Hoover with the Shrike, both engines shut down at 10' over the runway, loop, roll and dead stick landing with the airplane rolling up to the announcer after landing.
In the famous words of Clint Eastwood, a man's got to know his limitations.
 
jrs14855 said:
As I have posted before Sunrise Aviation at John Wayne Airport teaches turn back to pre solo students. VERY hostile environment around this airport and despite the long primary runway many of the GA operations are on the shorter runway. Video of the owner of Sunrise conducting tests in a 172 at a strip inland from John Wayne.
Click to expand...

Do you have a link?

Thanks,
 
It is done.

This is something that has been taut around the country in some of the training programs. We have been asked to demonstrate it in the past while flying with an instructor. I can't not speak for the 12, but for a 6-7-8 the rule of thumb that has been shown to us is go straight ahead to 400-500' AGL and pull power and come back around in a good nose down attitude as tight as you can be comfortable with. I would not recommend this for everyone or every type of aircraft, but if you practice it up high then work your way back down, it dose work and can be done with an RV. I can tell you that I have modified it a little when I don't like the trees or something around the airport I am leaving and want a little edge in case I were to loose the engine on departure. I get off the ground, turn 30* to the right and climb out. In this way if you have any power or other problem that forces you to make a landing call on the climb out, you have cut down the radius of the turn for a return to the runway if you elect to try and come back around. I like to practice this from time to time with no distractions. Never know if it may be needed some day. Hope this helps as it is just two cents on the subject. Yours, R.E.A. III #80888
 
It's been shown that the drag on a windmilling, non-feathered prop is comparable to having a disc of plywood the diameter of your prop disc mounted to your engine flange. If your engine *siezes*, or loses the prop entirely as in the case of the Pitts above, expect a much better glideslope.

From most to least drag:

1. Windmilling prop (failed forward crankshaft, but intact forward bearing - Spins freely with no engine compression)
2. Windmilling prop (engine off, but some compression present - ie. pulling the mixture)
3. Idling prop (engine running, at minimum power - ie. pulling the throttle to idle)
4. Stopped prop (engine siezed, prop gone, not turning, etc.)

Depending on the aircraft, if you can get the prop to stop turning, you can significantly increase your gliding distance. Probably not worth it on a climbout engine failure, but if you're in cruise at altitude, the benefits are there. Note that a low compression engine may not let you stop the prop (and keep it stopped) at your best glide speed.
 
The best glide speed for the -12 is between 59 kts (min sink) and 63 (max range). At those speeds I think the prop will be stopped.
 
If the runway is 6000 feet and the takeoff roll was 500 feet and you climbed at 900 feet a minute to 300 agl an executed a practice engine out 180 degree turn were you still over the runway when you pulled the throttle.
 
I did the same test but in my 7A with the lowest altitude of 600 AGL but no wind at KRIU. To account for the power at idle I lowered my flaps a tiny bit to create some drag. At 600 AGL I had to go on my breaks hard in order for not running out of the runway but this is when you know you have a perfectly good and running engine. In real emergency and that low of altitude, I would not able to do such maneuver, perhaps EVER. It is nerve wracking.
 
Turn Back

On a long runway with typical RV performance it no longer becomes a turn back maneuver but simply a modified pattern for a downwind landing. If you are at an airport where you will not get a lot of flak about not flying a standard pattern: if there is any crosswind, simply let the airplane drift downwind after takeoff. This positions you to make the initial turn at least partially into the wind.
If there was a strong headwind on takeoff on a long runway it will probably be best to make a 90 degree turn initially and then a 270 away form the runway. You may still be quite high but should be able to stop on the runway.
If you're at pattern altitude over the end of a long runway with lots of wind consider flying a complete pattern and starting the base leg at 600' on downwind ever if the base leg is aimed at the center of the runway.
A true story: A long long time ago at JFK a DC7 was fueled with jet fuel. Ceiling 200', one engine failed right after lift off. Indications that a second engine might be having problems. The captain started a 90/270, in the clouds, strictly timing. Rolled out of the turn on short final, perfectly lined up with the runway. 2 more engines quit in the turn, the last one quit just after touchdown . If he had hesitated a few seconds or had a conference about what to do this would have been an accident with xxxx fatal.
 
I've done this a couple times with my instructor and by myself in the 152. Less than 500 feet is the limit for the little Cessna. Wind is a big factor with this maneuver so don't get stuck on an altitude that you think might get you back to the runway without considering the wind. I do agree that you should know this limitation but it's a risky tactic close to the ground. Can't recommend practicing this without a good instructor that knows the plane.
 
Consider Prop type

Great discussion here. As everyone should be testing their own capabilities with their own plane please be sure to consider the type of prop you have as well. Not just whether or not it can feather but what material it is. Heavier props tend to windmill down to much lower speeds where lighter props like my wood prop stop windmilling at much higher speeds. I remember when I first started flying the -7 with the wood prop I was very concerned about how the prop would act in case I lost power. I did this at altitude as if I left the fuel selector on one side and ran out of fuel. At cruise speeds no problem, turn the selector to the other side and engine fires up since the prop is still windmilling. Now slow the plane down to pattern altitude speeds (similar to best glide speed ) and do the same... prop stops immediately. In my particular case if the prop stops it does not start windmilling again until you get to speeds past 100 knots. So my conclusion was at pattern altitude or climb out if I lose the juice, the prop is stopping and my glide ratio will be better than if it was windmilling.

Point is that everyone should consider the type of prop they have and test it out at altitude to see what will your prop do at lower speed or best glide speed... very important point that you should not overlook.
 
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