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Long body Actual glide with an engine out?


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We have all done the training(hopefully).  Simulated engine out, short approach.  I find myself, especially when I am alone, doing the calculations on trips, by saying, “if my engine failed, right now, where would I divert, how should I manage the energy?  I look at ForeFlight glide ring, I consult the manual, but I have never actually flown my Mooney without an engine .....

i had one engine out in a Cessna during my ppl with an instructor. It was in the pattern, so it was almost a non event, but I can tell you it was radically different from simulated, when the engine is close to idle. 
I’ve  often wondered how that would differ in my Mooney for real. 
The one thing that concerns me is estimating the approach, I mean you only get one.

How do you guys train for this?
Has anyone experienced this? 

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For the LB...

Train for it like any other Mooney...

know your best glide speed range based on weight...

know to reduce all the drag related devices...

There is an interesting discussion on the efficiency of gliding compared to the P51 around here....

Gumps, gumps, gumps... as many times as you can... it will be different when the fan is silent...

PP thoughts only, not a CFI...

Best regards,

-a-

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I did a simulation for it a few years ago to get a feel for it .  What stayed with me is that I can only make it to the runway if I fly a tight pattern so that's my rule in congested areas. 

Here is some info from memory and should not be too far off.  We pulled the power back and slowed down to 80-85 kts and observed the actual VSI reading which was very close to our calculation of 800-900 fpm clean (no flap, gear up).   We next set up the plane in the pattern abeam the numbers to the same VSI with gears down and minimal flap and necessary power to get 900 fpm.   We did this in Tracy which has light traffic and a long runway.

I was very disappointed to see how difficult it was in a Mooney compared to a Cessna but I am glad I did it.  The fist attempt did not go well but the second one was OK and if it was a short runway like KPAO,  I could have reshaped the fences at the end of the runway since coming short is not a good option.

This was one of the two things that my friend/instructor emphasized on since my family and I regularly flew to Truckee (KTRK).  The second one was quick exit from the Mooney in an emergency.  We could not find a good answer for that with one door :)

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On 5/16/2020 at 2:13 PM, Schllc said:

...

How do you guys train for this?
Has anyone experienced this? 

 

I fly regularly with an instructor in my 201, working toward my commercial certificate.  Frequently, after a few chandelles, he has me fly in the direction of an airfield and pull the power at 4000 - 5000 AGL, and steep spiral to full stop landing (of course making appropriate calls to the CTAF).  It really does inspire confidence that it can be done, and after a few of them, energy management becomes second nature, and you can hit the touchdown markers within commercial tolerances, dead stick.  Of course, having the engine in your back pocket for a go-around is a confidence booster...

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On 5/16/2020 at 8:13 PM, Schllc said:

The one thing that concerns me is estimating the approach, I mean you only get one.

In gliders it is one approach every time, the only time I did a go-around it was a 10ft bounce :D 

First, aim point for 1/2 runway on windy days and 1/3 runway on calm days, you can always bring it to the numbers when you are sure you will make it on final, speed control is crucial to judge the “height picture & glide progress” and get used to coming high without power on few of your landings from 300ft agl and you will get used to flare & touchdown with no power, if horizon is visible look at your aiming point & horizon & both runway ends 

Second, go up in the air and glide at various speeds and check your rate of decent, at 90kts if you see 900fpm then you are at 1:10 (with no wind), with headwinds you have to fly faster and tailwind slower, same for gusty days and calm days 

Whatever speed & pattern you fly while engine is off, 

- If you make runway overhead at 2500agl it should be no miss 

- If you make mid-downwind at 1000agl it should be no miss

- Anywhere else is iffy especially 1000agl upwind and 500agl final 

If you start fiddling with speed & height always swap between too profiles low & fast and high & slow, at 300agl wings should be level & speed just 10kts-15kts above stall with the runway ahead in reach, if the runway is not ahead just assume what is ahead is a runway and fly to it wing level few kts above stall speed 

If you think about 1000agl pattern on 3000ft runway, that is a 1:3 aspect ratio, if you make the downwind and fly at on dirty config with 1:4 glide you should make it, in a calm day don’t get much concerned by undershooting most likely you will be coming tight & hot on speed, in windy days, you will be surprised by speed loss as you go down (best glide speed increases & airspeed is lost from gusts & wind gradient) so have some 300ft or 20kts reserve...

My last practice was in Dec on +30kts wind day with 2000ft runway, I end up learning same lesson again, just run fast to final & sideslip you can think about it later :lol:

Drop the gear when the engine goes off or set pattern frequency, it is draggy in high speeds 90kts-130kts but the impact on slow speeds is not a show killer, people who fly bellow 80kts will not even notice it...

Edited by Ibra
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  • 1 month later...
On 5/17/2020 at 11:15 AM, M20S Driver said:

I did a simulation for it a few years ago to get a feel for it .  What stayed with me is that I can only make it to the runway if I fly a tight pattern so that's my rule in congested areas. 

Was this a computer simulation, or a practice power off 180 in an aircraft? When I did my Commercial I did quite a few power off 180’s in my 231 and my finding was the opposite of yours, I guess depending on what “tight” means. The configuration for the power off 180 maneuver is gear down but not flaps. Then pull the power to idle when abeam the numbers. If you put in any flaps you can’t take them out again. The best way to do the maneuver is to maintain best glide all the way through.

If I tried the Power Off 180 from less than .75 miles from the runway I could not make it. The magic number is .75 - 1.0 miles. If less than .75 you are forced to either turn 270 degrees or so and then back 90 or so because you blow through the final approach course and you do not make the runway. The turns need to be fairly gradual, remaining at best glide. If you turn too tight in an effort to make the final approach course - past a standard rate turn - you lose too much vertical lift,  drop like a rock, and won’t make it back either.

I did that work probably six years ago now and still fly my patterns at .75 to 1.0 from the runway. It has the added advantage of not forcing a tight base to final, which is literally a killer turn. I have done quite a few skidding stalls and recoveries, the likelihood of surviving one from final approach altitude is negligible.

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27 minutes ago, Davidv said:

@Deb got their commercial license in their Ovation 2, they may be able to share some tips after many power off 180 landings...

the REAL @Deb is a glider instructor, right @deb, er, David? :)

Here is a tip...imagine an arc from wingtip extending out in front of you and to the other wingtip. Anything in that arc you can glide to.

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13 minutes ago, mike_elliott said:

the REAL @Deb is a glider instructor, right @deb, er, David? :)

Here is a tip...imagine an arc from wingtip extending out in front of you and to the other wingtip. Anything in that arc you can glide to.

I made sure to use plural pronouns for that reason :) 

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6 hours ago, jlunseth said:

Was this a computer simulation, or a practice power off 180 in an aircraft? When I did my Commercial I did quite a few power off 180’s in my 231 and my finding was the opposite of yours, I guess depending on what “tight” means. The configuration for the power off 180 maneuver is gear down but not flaps. Then pull the power to idle when abeam the numbers. If you put in any flaps you can’t take them out again. The best way to do the maneuver is to maintain best glide all the way through.

If I tried the Power Off 180 from less than .75 miles from the runway I could not make it. The magic number is .75 - 1.0 miles. If less than .75 you are forced to either turn 270 degrees or so and then back 90 or so because you blow through the final approach course and you do not make the runway. The turns need to be fairly gradual, remaining at best glide. If you turn too tight in an effort to make the final approach course - past a standard rate turn - you lose too much vertical lift,  drop like a rock, and won’t make it back either.

I did that work probably six years ago now and still fly my patterns at .75 to 1.0 from the runway. It has the added advantage of not forcing a tight base to final, which is literally a killer turn. I have done quite a few skidding stalls and recoveries, the likelihood of surviving one from final approach altitude is negligible.

It was a practice partial power to simulate power off landing.  I had the gear out and speed-brakes deployed and used some power to get 900 fpm at 85 knots which is what I was getting with no power clean.  What stayed with me is that at 1000 feet AGL on a down wind, the runway has to stay a couple of feet inside my wing tip to ensure power off landing.

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5 hours ago, mike_elliott said:

the REAL @Deb is a glider instructor, right @deb, er, David? :)

Here is a tip...imagine an arc from wingtip extending out in front of you and to the other wingtip. Anything in that arc you can glide to.

Sage advice - I work with an ol'timer CFI in Vermont who came up as through Pan Am.  He told me the same visual trick.  It is a great visual trick - so with you and him giving it we KNOW it must be good advice.  I feel it is a tad conservative for our slick airplanes but not by much.  Its especially useful when lowish like 3 or 4k since hopefully by then you have really sited your landing spot whatever that might be, an airport, or hopefully a lovely field if not an airport.  For higher altitudes I think it must be mostly math and glide ratios, glide rings and winds aloft.  I had a real life engine out to dead stick landing at an airport and I started at 16k.  My best solution was to turn back 150 degrees to an airport something like a dozen miles behind me.

Edited by aviatoreb
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7 hours ago, Davidv said:

I made sure to use plural pronouns for that reason :) 

I guess it is much easier to land engine out with multi-crew :lol:

One thing about the glide rings in electronic flight bags (e.g. ForeFlight), you may be able to tweak the settings for the gliding ring to show a high patten countour (e.g. 2000ft agl) and sub-optimal glide ratio (e.g. 1:6 instead of 1:10)? once you are 2000agl on top of a descent spot you do whatever it takes* to be 1/ wing level and 10kts above stall speed in dirty config at 300ft agl on final and 2/ just ahead of you some nice long landing spot into wind 

1/ is a must for you to walk again and 2/ is must for aircraft to fly again 

I think gliders stops flying exact Vbg values bellow 1000ft agl, they just pick a sensible approach speed for the condition/runway and stick to it and then tighten/widen their pattern to mange the angle (other stick to a pattern and then go fast/slow to bleed height) 

 

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  • 4 weeks later...

On the flight back to North Las Vegas from Panguitch Utah yesterday, the route took us south of Cedar Breaks and north of Zion. I was not only paying attention to flat ground but also to flat ground with road access. There were only about 15 minutes or so after leaving the highway 89 corridor until we could see the flat ground around Hurricane Utah. The wind was about 20 knots off of the nose at 10500, so I was prepared to turn around if there was a problem. Flat ground on the top of a Mesa in a wilderness area would not have been my preference.

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23 minutes ago, flyer338 said:

I did not see it mentioned in this thread, so far. If you pull the propeller knob to max pitch and close the throttle (once you have decided there will not be a restart) the glide ratio will improve by as much as 20%. Try it.

And that’s a great thing to demonstrate. But, in a single engine airplane, after an engine failure (assuming no oil pressure) the prop goes to fine pitch. Statistically speaking you probably won’t have the option to change the prop blade angle.

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On the flight back to North Las Vegas from Panguitch Utah yesterday, the route took us south of Cedar Breaks and north of Zion. I was not only paying attention to flat ground but also to flat ground with road access. There were only about 15 minutes or so after leaving the highway 89 corridor until we could see the flat ground around Hurricane Utah. The wind was about 20 knots off of the nose at 10500, so I was prepared to turn around if there was a problem. Flat ground on the top of a Mesa in a wilderness area would not have been my preference.

I would think any flat ground in that area would be a welcome site, whether isolated or not. Beats mountains any day.
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2 minutes ago, KLRDMD said:

And that’s a great thing to demonstrate. But, in a single engine airplane, after an engine failure (assuming no oil pressure) the prop goes to fine pitch. Statistically speaking you probably won’t have the option to change the prop blade angle.

I do not claim to have done an exhaustive study, but from what I read in Kathryn’s Report and elsewhere, most engine outs are due to fuel problems, next are ignition problems, and problems that stop the engine from turning are a distant third. While a hard engine stoppage will stop the pilot from adjusting the propeller pitch, the stopped propeller reduces drag even more than a propeller in max pitch. I know from experience the propeller pitch can be controlled in flight even with the engine shut down (4 cyl. Lycoming).

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Sources of drag.... (Long Body)

1) Gear

2) Flaps

3) Speed Brakes

4) Prop Max RPM

For max glide put all the things away...

 

For max descent rate...

1) Gear down...

2) Speed brakes...

3) Prop full in... throttle closed...

4) Speed selected for Vle...

This is the down elevator mode... you will be at TPA in only a few minutes... :)

 

PP thoughts only, not a CFI..

Best regards,

-a-

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4 hours ago, carusoam said:

Sources of drag.... (Long Body)

1) Gear

2) Flaps

3) Speed Brakes

4) Prop Max RPM

For max glide put all the things away...

 

For max descent rate...

1) Gear down...

2) Speed brakes...

3) Prop full in... throttle closed...

4) Speed selected for Vle...

5) 45° banked spiral

This is the down elevator mode... you will be at TPA in only a few minutes... :)

 

PP thoughts only, not a CFI..

Best regards,

-a-

FTFY. It's impressive even clean, pegged the IVSI in my C at normal cruise speed! That would be 2000+ fpm.

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