PFL with mixture set to lean
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PFL with mixture set to lean
Just interested to know if anyone can see a (good) reason why an instructor would want me to do a PFL from 2000' with the mixture pulled? 
This was getting rechecked out in an SEP that was 20 minutes out of its 50 h service, flying at a non-ATC airfield, no one else in the circuit. After one PFL from the circuit at 1000' and two EFATOs - one at 1200' for a 180° back to the r/way with the benefit of a strongish wind - this was the last one he delivered to me.
Is there any overwhelming benefit to be gained from creating a realistic engine-out scenario, or was this just plain daft?
This was getting rechecked out in an SEP that was 20 minutes out of its 50 h service, flying at a non-ATC airfield, no one else in the circuit. After one PFL from the circuit at 1000' and two EFATOs - one at 1200' for a 180° back to the r/way with the benefit of a strongish wind - this was the last one he delivered to me.
Is there any overwhelming benefit to be gained from creating a realistic engine-out scenario, or was this just plain daft?
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A PFL is just that, a practice, trying such a thing with a modified engine control which would not be available in the real thing in my opinion is daft/dangerous.
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As someone who is currently learning PFLs, I am taught to pull the throttle back at Hi Key at about 2000ft to start the glide. This is the only requirement to change engine settings which I am taught.
In a real emergency of course the Emergency cockpit drills for an engine fire or failure are different! The mixture is then leaned for an engine fire and as a SA for an engine failure
In a real emergency of course the Emergency cockpit drills for an engine fire or failure are different! The mixture is then leaned for an engine fire and as a SA for an engine failure
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Even at idle the prop will still produce a little thrust, and you will have the comfort of knowing it is there.
It's a good way of demonstrating the environment you will find yourself in, in the event of a real engine failure. It sounds and feels different than simply pulling the throttle.
One of my instructors routinely pulled the mixture overhead the field at 2,000', and it was left that way until roll-out on the runway. After the initial nervousness, it is a very satisfying feeling to do it.
Just my experience, of course
p.s. I knew 'of' an instructor who would position the aircraft on a high final, give control to the student, pull the mixture then turn the ignition off and throw the keys over his shoulder into the back. Now THAT is daft!!
It's a good way of demonstrating the environment you will find yourself in, in the event of a real engine failure. It sounds and feels different than simply pulling the throttle.
One of my instructors routinely pulled the mixture overhead the field at 2,000', and it was left that way until roll-out on the runway. After the initial nervousness, it is a very satisfying feeling to do it.
Just my experience, of course
p.s. I knew 'of' an instructor who would position the aircraft on a high final, give control to the student, pull the mixture then turn the ignition off and throw the keys over his shoulder into the back. Now THAT is daft!!
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p.s. I knew 'of' an instructor who would position the aircraft on a high final, give control to the student, pull the mixture then turn the ignition off and throw the keys over his shoulder into the back. Now THAT is daft!!
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I think that is highly dodgy, though not unknown.
One instructor I used to fly with used to stop the prop as well; he used to do it on pleasure flights at 2000ft. Did it to me once... I let him fly it
A friend of mine once got an EFATO with the mixture pulled, which is worse. Luckily the engine restarted OK before they hit the ground.
Some are bound to end up in aviation
One instructor I used to fly with used to stop the prop as well; he used to do it on pleasure flights at 2000ft. Did it to me once... I let him fly it
A friend of mine once got an EFATO with the mixture pulled, which is worse. Luckily the engine restarted OK before they hit the ground.
Some are bound to end up in aviation
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Seems to me that the most essential PFL precaution is to ensure that an engine will respond when the exercise is over. I'm not convinced that pulling the mixture is the safest option.
Why not ask the guy?
Why not ask the guy?
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I am taught to pull the throttle back at Hi Key at about 2000ft to start the glide. This is the only requirement to change engine settings which I am taught.
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Actually, I'm a little bemused by the question:
To me a PFL is a practice forced landing. It's not done anywhere near a circuit of any kind - the major 'skill' part of a (P)FL is identifying, and putting yourself in a position to land into some field/area where you don't have the usual cues, nor (accurately) know the field elevation; also to ensure you don't loose track of flying the plane while you're doing that.
In these circumstances pulling the mixture, or doing anything that increases the chances of you actually finishing up in said field is a bit silly IMHO.
A 'PFL' into a known airfield is simply a glide approach, presuming you can land off it, not sure it's a big deal. I guess you're adding a bit more risk that you can't go around, but landing engine out shouldn't be much of an issue either.
This was getting rechecked out in an SEP that was 20 minutes out of its 50 h service, flying at a non-ATC airfield, no one else in the circuit. After one PFL from the circuit at 1000' and two EFATOs - one at 1200' for a 180° back to the r/way with the benefit of a strongish wind - this was the last one he delivered to me.
In these circumstances pulling the mixture, or doing anything that increases the chances of you actually finishing up in said field is a bit silly IMHO.
A 'PFL' into a known airfield is simply a glide approach, presuming you can land off it, not sure it's a big deal. I guess you're adding a bit more risk that you can't go around, but landing engine out shouldn't be much of an issue either.
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4Blues
By the fact that the poster you are referring is titled Grob Queen and refers to High Key I am guessing she (or perhaps he
) is flying with a RAF VGS unit in a Vigilant motor gilder.......and i think they have carb heat applied throughout as SOP.
Am I right GQ?
Hmm then again, vigilants don't have a mixture control so i am probably wide of the mark?
Moli
Edited to add having wracked my brains, Mil Grobs do have carb heat and it is applied at all times other than when at full power. I believe that some civil Grobs don't have carb heat.
By the fact that the poster you are referring is titled Grob Queen and refers to High Key I am guessing she (or perhaps he
) is flying with a RAF VGS unit in a Vigilant motor gilder.......and i think they have carb heat applied throughout as SOP.Am I right GQ?
Hmm then again, vigilants don't have a mixture control so i am probably wide of the mark?
Moli
Edited to add having wracked my brains, Mil Grobs do have carb heat and it is applied at all times other than when at full power. I believe that some civil Grobs don't have carb heat.
Last edited by Moli; 11th Jan 2012 at 20:24.
When I first started working as a flying instructor, pulling the mixture was the way the CFI wanted us to "fail" the engine for a forced approach. One day early in my instructing career, I was out with a new student and we ended up doing 2 full forced approached exercises. I felt that one more would be a good way to solidify the lesson but we were out of time so we went back home. After parking the aircraft the student went to shut down. He pulled out the mixture control and the engine died, but the knob did not stop at the usual spot and the student ended up pulling 6 inches of loose cable out. 
. The cable had failed at the carburetor rod end and it was only very good luck that it had not failed when we were doing the forced approach exercises.....
The next day a memorandum form the CFI required engine failures only be initiated by closing the throttle...........
. The cable had failed at the carburetor rod end and it was only very good luck that it had not failed when we were doing the forced approach exercises.....The next day a memorandum form the CFI required engine failures only be initiated by closing the throttle...........
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Ok, hands up and red-faced 
I might have unintentionally misled some of you good guys and gals with my use of "PFL". (I hope you'll forgive me, I didn't do either my flight training or ground school in English).
We were over the airfield at 2000', positioning for an "encadrement", in which the pilot is required to close the throttle and hopefully land on the runway. Highly unusual to pull the mixture as well, though, at least in our club.
Reading your replies (thanks), I'm a little surprised that for some of you at least, landing onto a runway with engine stopped is not unusual? It seems a risk too far imho. What if the engine doesn't restart in some unexpected situation? Are you ever 100% guaranteed to make a runway, even in the most benign conditions? What if you misjudge the wind, what if the runway is unexpectedly occupied? What if you overshoot?
I might have unintentionally misled some of you good guys and gals with my use of "PFL". (I hope you'll forgive me, I didn't do either my flight training or ground school in English).We were over the airfield at 2000', positioning for an "encadrement", in which the pilot is required to close the throttle and hopefully land on the runway. Highly unusual to pull the mixture as well, though, at least in our club.
Reading your replies (thanks
), I'm a little surprised that for some of you at least, landing onto a runway with engine stopped is not unusual? It seems a risk too far imho. What if the engine doesn't restart in some unexpected situation? Are you ever 100% guaranteed to make a runway, even in the most benign conditions? What if you misjudge the wind, what if the runway is unexpectedly occupied? What if you overshoot?
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FL, just to be clear, you're discussing a total engine shut-down starting at 2000' overhead?
The 180 return to the runway is just as worrying I would have thought - apart from anyone else using the runway (maybe non-radio?). When you say a favourable wind, how strong was it?
The 180 return to the runway is just as worrying I would have thought - apart from anyone else using the runway (maybe non-radio?). When you say a favourable wind, how strong was it?
I can't help feel that there's a lot of "it depends" here.
I've had the ignition turned off on me by an instructor in a microlight at about 1000 ft - overhead a 4 mile x 1 mile landable beach. It was an enjoyable exercise.
I can't say I'd be particularly worried at an instructor turning the engine off in a motor glider - such as a Grob 109b, at 2000ft most places. Many people will do that themselves, because it is both "motor" and "glider".
I would be somewhat disturbed at somebody turning the mixture to ICO on me in an Arrow at 2000ft overhead a narrow short runway. If I was in, say, a Pegasus XL-R I'd be altogether more relaxed about it.
Also at 2000ft perhaps the correct thing to do is to re-start the engine, and the instructor was expecting that and just assuming that if there was a failure to re-start, then HE would land on the airfield? With that much height, I'd certainly expect if I was the checkee to be attempting a re-start (or at-least touch drills), and as an instructor I'd expect them to do that.
I'm not sure if they still do, but microlight flying competitions used to routinely include spot landings from an engine stop at (1000ft?) in the overhead.
It all depends !
G
I've had the ignition turned off on me by an instructor in a microlight at about 1000 ft - overhead a 4 mile x 1 mile landable beach. It was an enjoyable exercise.
I can't say I'd be particularly worried at an instructor turning the engine off in a motor glider - such as a Grob 109b, at 2000ft most places. Many people will do that themselves, because it is both "motor" and "glider".
I would be somewhat disturbed at somebody turning the mixture to ICO on me in an Arrow at 2000ft overhead a narrow short runway. If I was in, say, a Pegasus XL-R I'd be altogether more relaxed about it.
Also at 2000ft perhaps the correct thing to do is to re-start the engine, and the instructor was expecting that and just assuming that if there was a failure to re-start, then HE would land on the airfield? With that much height, I'd certainly expect if I was the checkee to be attempting a re-start (or at-least touch drills), and as an instructor I'd expect them to do that.
I'm not sure if they still do, but microlight flying competitions used to routinely include spot landings from an engine stop at (1000ft?) in the overhead.
It all depends !
G
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to be honest i ain't that bother at the thought.
My main concern would be the cooling of the engine and any potential damage to it.
If the gingers said thats fine and there was some where to plant it why not but there ain't going to be that much difference to flight idle
My main concern would be the cooling of the engine and any potential damage to it.
If the gingers said thats fine and there was some where to plant it why not but there ain't going to be that much difference to flight idle
The one time I was worried: when the examiner cut both magneto's just after take-off, perhaps 3 feet off the ground... scary scary scary, and as I was on my exam there was no shortage of adrenaline anyway.
It has happened to me since, on renewal test and the like, overhead at 1000' or so, and it never really worried me. The shorter the runway, the better one must be at side-slipping, just as much as required. But the sound of the wind is eerie. Suppose glider pilots are better used to that.
It has happened to me since, on renewal test and the like, overhead at 1000' or so, and it never really worried me. The shorter the runway, the better one must be at side-slipping, just as much as required. But the sound of the wind is eerie. Suppose glider pilots are better used to that.