Engine failure below Vmcg
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My 2 cents...I don't believe a sub Vmc take off in a C340 is that dangerous...but requires a certain mindset. Luck favors the prepared.
Most of us(I think) started out in singles, and should have been springloaded for and engine out scenario for an off airport landing. Having been a flight instructor doing 20 engine outs a week...prepared me for a real 15 mile unintended glide..
Once I got into light twins, the mindset was to fly. Surprise, surprise light twins and many turboprops do about 300 FPM on one engine if the conditions are right, and the pilot knows what he's doing. So I had to keep in the back of my mind that I might still have to put the plane down somewhere after take off...enroute probably not.
Can't argue that planning VR after Vmc is prudent...but the ops might require short field, or soft field techniques...so the mindset is to understand that sub Vmc engine out, you pull the power back untill the roll tendency goes away, given the appropriate control surface deflections. The plane will probably not go up, but it might stay level or descend at a slower rate then a single..
I have felt under these scenarios..getting the plane off the ground, then accelerate past Vmc, in or near ground effect, talkes almost little time...and your there...
Taken that all the above doesnt work given the conditions your back to being like a single, a glider, looking for a place to land...thousands of pilots think like this every day...
Most of us(I think) started out in singles, and should have been springloaded for and engine out scenario for an off airport landing. Having been a flight instructor doing 20 engine outs a week...prepared me for a real 15 mile unintended glide..
Once I got into light twins, the mindset was to fly. Surprise, surprise light twins and many turboprops do about 300 FPM on one engine if the conditions are right, and the pilot knows what he's doing. So I had to keep in the back of my mind that I might still have to put the plane down somewhere after take off...enroute probably not.
Can't argue that planning VR after Vmc is prudent...but the ops might require short field, or soft field techniques...so the mindset is to understand that sub Vmc engine out, you pull the power back untill the roll tendency goes away, given the appropriate control surface deflections. The plane will probably not go up, but it might stay level or descend at a slower rate then a single..
I have felt under these scenarios..getting the plane off the ground, then accelerate past Vmc, in or near ground effect, talkes almost little time...and your there...
Taken that all the above doesnt work given the conditions your back to being like a single, a glider, looking for a place to land...thousands of pilots think like this every day...
This thread reminds me of one persons name [especially JT's words]
Aaliyah Haughten
and her stupid coked-up unqualified 405B pilot in N884FG [still registered creepy]
anyways look it up ---it brings to light a few of these issues!!!
PA
Aaliyah Haughten
and her stupid coked-up unqualified 405B pilot in N884FG [still registered creepy]
anyways look it up ---it brings to light a few of these issues!!!
PA
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Angels 60,
quote:"....so the mindset is to understand that sub Vmc engine out, you pull the power back untill the roll tendency goes away, given the appropriate control surface deflections. The plane will probably not go up, but it might stay level or descend at a slower rate then a single.."
This will not work, assuming this happens during/just after takeoff. Here's why:
1 You cannot pull the power back as you need all power available, especially when your aircraft is heavy. So, in your case when you do pull the power back, you are not going to climb and with many twins you will probably descend (..and the subsequent results).
2 Some twins need autofeather. For example the Beech 1900. After engine failure and getting control of the aircraft, first thing you want to check if the autofeather kicked in or not. If not, then manual feather. Piston twins perform worse.
3 You do not have time in your mentioned case to properly determine which engine failed en which throttle to cut. Changes are that you would chop the live engine.
I understand what you're saying but there's simply not enough time to react and not enough performance.
cheers
quote:"....so the mindset is to understand that sub Vmc engine out, you pull the power back untill the roll tendency goes away, given the appropriate control surface deflections. The plane will probably not go up, but it might stay level or descend at a slower rate then a single.."
This will not work, assuming this happens during/just after takeoff. Here's why:
1 You cannot pull the power back as you need all power available, especially when your aircraft is heavy. So, in your case when you do pull the power back, you are not going to climb and with many twins you will probably descend (..and the subsequent results).
2 Some twins need autofeather. For example the Beech 1900. After engine failure and getting control of the aircraft, first thing you want to check if the autofeather kicked in or not. If not, then manual feather. Piston twins perform worse.
3 You do not have time in your mentioned case to properly determine which engine failed en which throttle to cut. Changes are that you would chop the live engine.
I understand what you're saying but there's simply not enough time to react and not enough performance.
cheers
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Cap Loko,
Unless you have the performance manuel out on this specific twin you can't make any behind the key board judgement on performance...I didn't specify sea level at 50 below zero or high hot and heavy, in Colorado.
If you find autofeather on a light twin like a C340 let me know...
Time is relative, some pilots can't make decision infront of thier PC with regard to performance, much less up in a plane.
Some people are very comfortable flying planes...very comfortable.
Your statement simply negates the fact that light twins on a daily basis operate out of remote, unimproved stips all over the world..and they all don't have the luxury flying the numbers in a best case scenario as is commonly considered. Start reading up on short field and unimproved operations and you will understand a little about the 'mindset' of a short field pilot vs one that flies out of 10000 ft runways in turbine equipment. One size does not fit all.
Unless you have the performance manuel out on this specific twin you can't make any behind the key board judgement on performance...I didn't specify sea level at 50 below zero or high hot and heavy, in Colorado.
If you find autofeather on a light twin like a C340 let me know...
Time is relative, some pilots can't make decision infront of thier PC with regard to performance, much less up in a plane.
Some people are very comfortable flying planes...very comfortable.
Your statement simply negates the fact that light twins on a daily basis operate out of remote, unimproved stips all over the world..and they all don't have the luxury flying the numbers in a best case scenario as is commonly considered. Start reading up on short field and unimproved operations and you will understand a little about the 'mindset' of a short field pilot vs one that flies out of 10000 ft runways in turbine equipment. One size does not fit all.
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Luck favors the prepared.
Start reading up on short field and unimproved operations and you will understand a little about the 'mindset' of a short field pilot vs one that flies out of 10000 ft runways in turbine equipment.
I have felt under these scenarios..getting the plane off the ground, then accelerate past Vmc, in or near ground effect, talkes almost little time...and your there...
Can't argue that planning VR after Vmc is prudent...but the ops might require short field, or soft field techniques...so the mindset is to understand that sub Vmc engine out, you pull the power back untill the roll tendency goes away, given the appropriate control surface deflections.
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Guppy, I am a CFII, MEII...I used to TEACH Vmc recovery!
You've never actually experienced it though, have you? Below Vmc, low level, on takeoff...
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Yes.
You tried to "simulate" it. Meaning you expected it, you saw it coming. You did this below Vmc, close to the ground, on takeoff? You haven't actually experienced it when it's really happening.
You might be smart enough to listen to more knowledgeable and experienced posters here who strongly suggest you don't put yourself in a position to be experiencing an engine failure below a speed at which it's controllable, and who tell you, BEFORE you have to experience it for yourself, that the airplane can roll over on your faster than you imagine it can. Much faster.
Then again, like your alter ego's here that were banned, you still won't listen, still want to reinvent the wheel, still think you can do it better. You may end up killing yourself to learn otherwise, but like the drowing man who can't be passed a glass of water, at least you'll have your way.
You tried to "simulate" it. Meaning you expected it, you saw it coming. You did this below Vmc, close to the ground, on takeoff? You haven't actually experienced it when it's really happening.
You might be smart enough to listen to more knowledgeable and experienced posters here who strongly suggest you don't put yourself in a position to be experiencing an engine failure below a speed at which it's controllable, and who tell you, BEFORE you have to experience it for yourself, that the airplane can roll over on your faster than you imagine it can. Much faster.
Then again, like your alter ego's here that were banned, you still won't listen, still want to reinvent the wheel, still think you can do it better. You may end up killing yourself to learn otherwise, but like the drowing man who can't be passed a glass of water, at least you'll have your way.
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I haven't had an emergency yet that was planned, but I was evidentely, ready for it..
In any event YOUR RIGHT, no pilot could handle a sub Vmc take off without killing everyone on board. No matter what the temp, the weight, how close Vmc is to Vx, and not even if this guy's full time job was teaching multi students all day long, not even if he cleared a cliff at the end and glided, adding airspeed..not even if he flew out in ground effect, not even if he reduced power on a super cold day could he climb out...not even if he just plopped the plane back down once the engine quit below Vmc.......wow!
Your right Guppy, Thank You, what was I thinking?
In any event YOUR RIGHT, no pilot could handle a sub Vmc take off without killing everyone on board. No matter what the temp, the weight, how close Vmc is to Vx, and not even if this guy's full time job was teaching multi students all day long, not even if he cleared a cliff at the end and glided, adding airspeed..not even if he flew out in ground effect, not even if he reduced power on a super cold day could he climb out...not even if he just plopped the plane back down once the engine quit below Vmc.......wow!
Your right Guppy, Thank You, what was I thinking?
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What were you thinking? Not for me to say.
What you aren't thinking is obvious, however. That is, you're not thinking in terms of someone with real world experience, otherwise you'd know better.
Luck has no place in the business, any more than departing at ridiculously low speeds and hoping one won't have a problem until one gains enough speed to actually control the airplane in the event of an assymetrical thrust condition.
You've called upon the concept of pilots who fly light twins from short, rough airfields, the world over. I've certainly done enough of this...but have you? You see, you cite these ideas, these points of view, from a position of guesswork, not actual experience; you promulgate dangerous concepts and do it in ignorance, which is the same as luck, the same as guesswork.
You're also embarassing yourself.
What you aren't thinking is obvious, however. That is, you're not thinking in terms of someone with real world experience, otherwise you'd know better.
Luck has no place in the business, any more than departing at ridiculously low speeds and hoping one won't have a problem until one gains enough speed to actually control the airplane in the event of an assymetrical thrust condition.
You've called upon the concept of pilots who fly light twins from short, rough airfields, the world over. I've certainly done enough of this...but have you? You see, you cite these ideas, these points of view, from a position of guesswork, not actual experience; you promulgate dangerous concepts and do it in ignorance, which is the same as luck, the same as guesswork.
You're also embarassing yourself.
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Basic character will always out
Strangely enough Guppy here's what I wrote to our little Angel several hours ago:
You are still and always will be ssg albeit desperately trying to write as if normal and with the total arrogance chip turned down to merely simmer.
Regards
Rob
PPRuNe Admin
Regards
Rob
PPRuNe Admin
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Angels 60,
I do have plenty of "realworld" experience operating from dirtstrips in the African bush. I made sure I always flew by the numbers, no mather what the boss wants, no matter if we are in a hurry etc, etc....no excuses
If you have an engine failure just after takeoff and -yes even slightly- below VMC you will be in for a nasty surprise. In case you have no idea: plane will roll over in the blink of an eye, just as SNS3Guppy explained.
fly safe
I do have plenty of "realworld" experience operating from dirtstrips in the African bush. I made sure I always flew by the numbers, no mather what the boss wants, no matter if we are in a hurry etc, etc....no excuses
If you have an engine failure just after takeoff and -yes even slightly- below VMC you will be in for a nasty surprise. In case you have no idea: plane will roll over in the blink of an eye, just as SNS3Guppy explained.
fly safe
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That's not true..Vmc is predicated on standard conditions...such as full power, 5% deflection...
Find me different Vmc numbers at different altitudes, weights and temps on a light aircraft, differing power ranges......you won't.
Not only is it possible to fly below Vmc and the plane doesn't roll over, but I have done it.
Keeping the Vmc roll from happening is a very easy thing to do, pull back enough power to keep the plane level...now with the power that you do have...what is it doing? Climbing, descending...??
Imagine being a plane that is very light, in Alaska, 20 below, power needed to keep that plane up will be much less on one engine...that reduced power setting on the good engine might be enough to keep it up in the air.
120 degrees in Africa?...sure, I wouldn't try it....No one in there right mind will intentionaly try to fly below Vmc, but the ops, or situaton might require it..better be ready for it, then just crash like everyone else.
And let's face it, when it comes to safety, don't throw stones..if your running flex at an airline, planning balanced field into the stopway with 200 people in the back, looking over at your 600 hr FO, it's a hard sell to preach safety...
With the advent of VGs, putting Vmc typicaly below stall, this issue is almost moot these days on something cabin class like a Cessna twins...
Find me different Vmc numbers at different altitudes, weights and temps on a light aircraft, differing power ranges......you won't.
Not only is it possible to fly below Vmc and the plane doesn't roll over, but I have done it.
Keeping the Vmc roll from happening is a very easy thing to do, pull back enough power to keep the plane level...now with the power that you do have...what is it doing? Climbing, descending...??
Imagine being a plane that is very light, in Alaska, 20 below, power needed to keep that plane up will be much less on one engine...that reduced power setting on the good engine might be enough to keep it up in the air.
120 degrees in Africa?...sure, I wouldn't try it....No one in there right mind will intentionaly try to fly below Vmc, but the ops, or situaton might require it..better be ready for it, then just crash like everyone else.
And let's face it, when it comes to safety, don't throw stones..if your running flex at an airline, planning balanced field into the stopway with 200 people in the back, looking over at your 600 hr FO, it's a hard sell to preach safety...
With the advent of VGs, putting Vmc typicaly below stall, this issue is almost moot these days on something cabin class like a Cessna twins...
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tankdriver;
I'm not talking about a light twin flying enroute if that is what you mean. Actually, I like your example of the light twin flying in Alaska enroute just below published Vmc and is a good example for demonstration purposes.
Actual Vmc will be different for every flight. I'm not a test pilot so better stick with the performance tables/V speeds.
Some people keep talking about reducing engine power. Well,again, with many (if not most) twins if you do that during takeoff after rotation, you will not be able to climb. That means not clearing obstacles in the takeoff path. You will find some examples of people who've done that elsewere in the forum.
Also nothing wrong planning a (balanced) takeoff with ASD(R) in the stopway. As long as TOD(R) is within the clearway. A takeoff doesnt have to be balanced by the way.
I'm not talking about a light twin flying enroute if that is what you mean. Actually, I like your example of the light twin flying in Alaska enroute just below published Vmc and is a good example for demonstration purposes.
Actual Vmc will be different for every flight. I'm not a test pilot so better stick with the performance tables/V speeds.
Some people keep talking about reducing engine power. Well,again, with many (if not most) twins if you do that during takeoff after rotation, you will not be able to climb. That means not clearing obstacles in the takeoff path. You will find some examples of people who've done that elsewere in the forum.
Also nothing wrong planning a (balanced) takeoff with ASD(R) in the stopway. As long as TOD(R) is within the clearway. A takeoff doesnt have to be balanced by the way.
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Cap Loko,
I think we are on the same page actualy. Imagine soft field take off technique in a twin:
Full power, the nose off ASAP to reduce drag, plane flies it's self off(sub Vmc/just above stall) stay in ground effect, accelerate.
If right as the plane lifts off sub Vmc...engine quits..then you chop power and land..easy..
or accelerate to Vmc in ground effect, then accelerate to Vx...your golden.
And what are the chances your engine, will fail right there in that ten knot window...?
If your runways are so short and nasty that a soft/short field take off means that as soon as the gear is off, you run out of runway...then yeah, that's sketchy..but thats how bush pilots in singles do it...
Look at it this way...a million people a day take off single engine, knowing that the engine could quit and they become a glider...sometimes in a twin you have to think that way too...or even a jet..
It's wishfull thinking that all planes will fly, all the time...none the less, I want options, and safety...and in a perfect world, if one engine dies, I want the plane to fly, that's how I plan it..sometimes plans fall short...
I think we are on the same page actualy. Imagine soft field take off technique in a twin:
Full power, the nose off ASAP to reduce drag, plane flies it's self off(sub Vmc/just above stall) stay in ground effect, accelerate.
If right as the plane lifts off sub Vmc...engine quits..then you chop power and land..easy..
or accelerate to Vmc in ground effect, then accelerate to Vx...your golden.
And what are the chances your engine, will fail right there in that ten knot window...?
If your runways are so short and nasty that a soft/short field take off means that as soon as the gear is off, you run out of runway...then yeah, that's sketchy..but thats how bush pilots in singles do it...
Look at it this way...a million people a day take off single engine, knowing that the engine could quit and they become a glider...sometimes in a twin you have to think that way too...or even a jet..
It's wishfull thinking that all planes will fly, all the time...none the less, I want options, and safety...and in a perfect world, if one engine dies, I want the plane to fly, that's how I plan it..sometimes plans fall short...
