Spinning - recommendations please
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Mad Jock
Interesting discussion! I touched on spiral dives that could warrant a discussion too as being an uncomfortable manouvre which holds risk but one which is taught and put up with if unpleasant.
I read an article called "beyond VNE" Obviously not an area that pilots usually operate in willingly.
It was not the speed itself which broke the aircraft but the pilot inputs yet in pilots minds VNE conjures up a point where the aircraft will explode
in the said article they recommended dropping the gear rather than control inputs to slow the aircraft down even though the speed would be well over the gear speed. How many pilots would consider that rather than trying to pull out of the dive at very high speed? Yet it could save your life.
We can all be taught to fly to the expected it when we go out of that safe boundary that our descisions right or wrong determine the outcome.
Added this snippet
Pace
Interesting discussion! I touched on spiral dives that could warrant a discussion too as being an uncomfortable manouvre which holds risk but one which is taught and put up with if unpleasant.
I read an article called "beyond VNE" Obviously not an area that pilots usually operate in willingly.
It was not the speed itself which broke the aircraft but the pilot inputs yet in pilots minds VNE conjures up a point where the aircraft will explode
in the said article they recommended dropping the gear rather than control inputs to slow the aircraft down even though the speed would be well over the gear speed. How many pilots would consider that rather than trying to pull out of the dive at very high speed? Yet it could save your life.
We can all be taught to fly to the expected it when we go out of that safe boundary that our descisions right or wrong determine the outcome.
Added this snippet
"In an emergency, the landing gear may be used to create additional drag. Should disorientation occur under instrument conditions, the lowering of the landing gear will reduce the tendency for excessive speed build-up. This procedure would also be appropriate for a non-instrument rated pilot who unavoidably encounters instrument conditions or in other emergencies such as severe turbulence."
"Should the landing gear be used at speeds higher than the maximum extension speed [145 KIAS], a special inspection of the gear doors in accordance with shop manual procedures is required, with repair as necessary."
Beechcraft is telling us is that, at unusual airspeeds, we will start losing the wings before landing gear components (except for the gear doors) if the gear is lowered at airspeeds in excess of 145 KIAS. Easy enough to complete a flight safely with a bent gear door (just leave the gear down, please). Not so easy to complete a flight missing parts of the tail.
In a V35 in a 30-degree descent, if you chop the power and drop the gear you'll decelerate to 153 KIAS (0.9 Vno) at a 7,753 fpm descent rate. Leave the gear up and the power in and you'll be flying at 256 KIAS (1.3 Vne / 1.17 Vd) and descending at 13,000 fpm. Add full power and you'll be at 270 KIAS (1.4 Vne / 1.24 Vd) and hurtling downward at 13,700 fpm
"Should the landing gear be used at speeds higher than the maximum extension speed [145 KIAS], a special inspection of the gear doors in accordance with shop manual procedures is required, with repair as necessary."
Beechcraft is telling us is that, at unusual airspeeds, we will start losing the wings before landing gear components (except for the gear doors) if the gear is lowered at airspeeds in excess of 145 KIAS. Easy enough to complete a flight safely with a bent gear door (just leave the gear down, please). Not so easy to complete a flight missing parts of the tail.
In a V35 in a 30-degree descent, if you chop the power and drop the gear you'll decelerate to 153 KIAS (0.9 Vno) at a 7,753 fpm descent rate. Leave the gear up and the power in and you'll be flying at 256 KIAS (1.3 Vne / 1.17 Vd) and descending at 13,000 fpm. Add full power and you'll be at 270 KIAS (1.4 Vne / 1.24 Vd) and hurtling downward at 13,700 fpm
Last edited by Pace; 18th Feb 2009 at 11:24.
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Not so Mad Jock,thank you
Glider ,great idea,I had a lesson last year at, Tibbenham which is half a mile for our airstrip and really enjoyed it.
The really strange thing is I almost forgot it had no engine,we flew to a speed using attitude and then I did steep turns and stalls,as long as I kept the speed correct it was just like flying the L4 Cub,well almost
Lister
The really strange thing is I almost forgot it had no engine,we flew to a speed using attitude and then I did steep turns and stalls,as long as I kept the speed correct it was just like flying the L4 Cub,well almost
Lister
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You will find almost all engineering systems are exactly the same when it comes to control application and rate there of. The control stability and also peak strain is related to rate of input.
My type has a Vmo of 230knts and its got nothing to do with the wings falling off. I think they were tested to 500knts but you get supersonic shock waves coming off the props at 320knts and the limiting factor is the front windows which BAe cocked up the testing of firing segulls at them so we are stuck with 230knts in the UK compared to 250knts in the rest of the world. And the one thing that never breaks is the sodding overspeed alarm. I so I for one will not be chucking the gear out because we are 20knots to fast.
I agree spiral dives are not very pleasant if they are developed to far and the controls are used agriculturally. But again it comes back to flying with attention to the correct attitude. Even the recovery can be horrible or a none event. Gash hard handling feels wrong, smooth reduction of power plus carb heat,while rolling in the level wings, when level gradual increasing back pressure followed by gradual release of said pressure as the tail begins to do its job. Then smooth in with the power when the nose is back at the correct attitude and the aircraft is back at level flight, give it a minute to make sure the carb heat has done its job and jobs a good one. All the problems with G stalls and the like are taken care of by the way the controls are handled.
There was only one exercise when I made the students use sharp control inputs and that was the roll in to steep turns. In my view it is an emergency avoidance exercise and a such all the benefit you have gained by looking after your aircraft the other 99.9% of the time is well used if you don't hit anything.
My type has a Vmo of 230knts and its got nothing to do with the wings falling off. I think they were tested to 500knts but you get supersonic shock waves coming off the props at 320knts and the limiting factor is the front windows which BAe cocked up the testing of firing segulls at them so we are stuck with 230knts in the UK compared to 250knts in the rest of the world. And the one thing that never breaks is the sodding overspeed alarm. I so I for one will not be chucking the gear out because we are 20knots to fast.
I agree spiral dives are not very pleasant if they are developed to far and the controls are used agriculturally. But again it comes back to flying with attention to the correct attitude. Even the recovery can be horrible or a none event. Gash hard handling feels wrong, smooth reduction of power plus carb heat,while rolling in the level wings, when level gradual increasing back pressure followed by gradual release of said pressure as the tail begins to do its job. Then smooth in with the power when the nose is back at the correct attitude and the aircraft is back at level flight, give it a minute to make sure the carb heat has done its job and jobs a good one. All the problems with G stalls and the like are taken care of by the way the controls are handled.
There was only one exercise when I made the students use sharp control inputs and that was the roll in to steep turns. In my view it is an emergency avoidance exercise and a such all the benefit you have gained by looking after your aircraft the other 99.9% of the time is well used if you don't hit anything.
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My type has a Vmo of 230knts and its got nothing to do with the wings falling off. I think they were tested to 500knts but you get supersonic shock waves coming off the props at 320knts and the limiting factor is the front windows which BAe cocked up the testing of firing segulls at them so we are stuck with 230knts in the UK compared to 250knts in the rest of the world. And the one thing that never breaks is the sodding overspeed alarm. I so I for one will not be chucking the gear out because we are 20knots to fast.
What is your type? I fly Citations and it is usual to descend with speeds close to VNE in smooth air. As such it is also prone to the overspeed reminding you that your on it
I feel the article was more directed at a serious dive after loss of control.
If you look at the Bonanza figures regarding speeds and descent rates it is easy to see the argument for dropping the gear and avoiding not being able to pull out of the dive.
Pace
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The mighty Jetstream 31/32 negative auto pilot clockwork instruments, built like a brick **** house. And the overspeed alarm is bloody loud you can hear it in the rear row of seats.
But a pilots aircraft to fly and I think they are great fun.
I know what you mean about the article but if you just do the obvious things smoothly and efficiently you can deal with truly horrendous unusual attitudes without pulling the wings off. As long as there is still airflow over the control surfaces you should be able to sort it without breaking anything.
But a pilots aircraft to fly and I think they are great fun.
I know what you mean about the article but if you just do the obvious things smoothly and efficiently you can deal with truly horrendous unusual attitudes without pulling the wings off. As long as there is still airflow over the control surfaces you should be able to sort it without breaking anything.
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I always said that fear keeps aviators alive. Fear prevents (Or goes some way towards preventing) people from doing things they really shouldn't. However, you need to have the necessary skills and experience to be able to react correctly when something frightening happens otherwise you panic or just cover your eyes and wait for it to stop (The latter can be quite and effective recovery technique in many aircraft!!)
I agree with what has been said earlier about the training emphasis being on preventing the situation developing in the first place. Typical non-aerobatic aircraft are stable enough that they don't roll over and die. When spinning for example there is a whole process to go through before the spin is properly developed. If you've let it get that far you have already ignored a whole host of very obvious warning signs and uncomfortable sensations so you're unlikely to know what to do to recover.
However, by virtue of being a glider pilot for many years I have a fair amount of experience in spinning, spiral dives etc. including excercises where you cover your eyes whilst the instructor initiates the manouver and then hands over to you to recover (With eyes open of course!!). Also demonstrations of an incorrect recovery actions and how to correct the mistake. Having explored the extremities of the aircraft's performance I feel confident enough to practise stalls/spins etc. every now and then just to remind myself what the sensations are like.
Although I wouldn't argue that any of this is strictly necessary for your average PPL pilot I am very glad to have the extra strings in my bow and would recomment it to anyone.
re Vne, I was always told it is much better to exceed Vne in a straight dive than pull hard on the controls to avoid the overspeed. At Vne you are already some way above Vmo so the likelyhood of something falling off when you pull hard on the stick is much higher.
I agree with what has been said earlier about the training emphasis being on preventing the situation developing in the first place. Typical non-aerobatic aircraft are stable enough that they don't roll over and die. When spinning for example there is a whole process to go through before the spin is properly developed. If you've let it get that far you have already ignored a whole host of very obvious warning signs and uncomfortable sensations so you're unlikely to know what to do to recover.
However, by virtue of being a glider pilot for many years I have a fair amount of experience in spinning, spiral dives etc. including excercises where you cover your eyes whilst the instructor initiates the manouver and then hands over to you to recover (With eyes open of course!!). Also demonstrations of an incorrect recovery actions and how to correct the mistake. Having explored the extremities of the aircraft's performance I feel confident enough to practise stalls/spins etc. every now and then just to remind myself what the sensations are like.
Although I wouldn't argue that any of this is strictly necessary for your average PPL pilot I am very glad to have the extra strings in my bow and would recomment it to anyone.
re Vne, I was always told it is much better to exceed Vne in a straight dive than pull hard on the controls to avoid the overspeed. At Vne you are already some way above Vmo so the likelyhood of something falling off when you pull hard on the stick is much higher.
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re Vne, I was always told it is much better to exceed Vne in a straight dive than pull hard on the controls to avoid the overspeed. At Vne you are already some way above Vmo so the likelyhood of something falling off when you pull hard on the stick is much higher.
Without doubt it is far better to be taught to avoid stalls, spins, spiral dives etc.
One thing I have found out in aviation is these things come up and bite you when you least expect them to.
In a previous post i explained how I nearly landed a twin gear up probably 2 feet from hitting the props yet I had it well ingrained to avoid that ever happening.
Luckely in that situation I reacted like lighting.
It is when we are distracted or dealing with other problems that the big one happens and as with the stall, spin, spiral situation. Although we may be taught to avoid till the cows come home there may come a time when we need the knowledge and skills of actually having experienced those conditions.
As you said you are glad of the training and I am sure there cannot be an arguement that a pilot so trained is not better equipt should the full thing ever happen to him no matter how unlikely.
Regarding VNE dives and I am talking about a situation where there is high speed and not a lot of airspace to recover in dropping the gear (if you have it
can save your life.Pace
When spinning for example there is a whole process to go through before the spin is properly developed
The Pilot's Lounge #131: Spin Training
I don't mind scaring instructor students however - if they haven't experienced it by the time they do their instructor training then they will experience it on the spin session that I do with them. It can easily take two rotations for them to stop the gyrations amidst the swearing after realizing that I (playing his student) have suddenly "lost control" - he had seen turns like this many times before and didn't identify the subtle signs of the imminent stall in this situation. Its not in the PPL syllabus. He had seen lots of stalls from straight flight with plenty of time to patter on the symptoms of the approaching stall. He wasn't expecting it as the pre-flight brief only covered normal spin entries and we'd just done lots of those so he was familiar with the normal process to get it into a fully developed spin.
In the debrief I often get "Does that happen often?" and the answer is "Usually only once in your lifetime."
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re Vne, I was always told it is much better to exceed Vne in a straight dive than pull hard on the controls to avoid the overspeed. At Vne you are already some way above Vmo so the likelyhood of something falling off when you pull hard on the stick is much higher.
I am given to understand that under JAR regs (and I suspect this will vary by aircraft category), the aircraft has to withstand a 50% overstress in G-loading for 30 sec, and still fly (you may not be able to re-use the airframe, and it may completely expire at 31 sec). The testing for velocity requires that the aircraft is flown to the maximum design dive speed, and Vne is set 10% lower.
Therefore you have (loosely speaking) a 10% margin on Vne, and a 50% margin on G. I'm also told that flutter is the likely limitation beyond Vne, and onset is rapid, and rapidly destructive. Obviously this is likely to be somewhat airframe dependant.
I'm also interested regarding V*m*o - I presume that's more applicable for a/c that also have mach limitations / Mmo - it's not a number I've ever found defined for anything I've flown.
Thanks for that link to the pilot's lounge. A lot of interesting things are coming out in this thread. I used to be an FI, and I fly gliders and instruct on three axis microlights, so I can relate to a lot of peoples experiences here. The more I think about this, the more convinced I am that ALL pilots should be able to recover from a full spin, and a spiral dive, before their formal training is completed. The first time to see either one is not on your own, or even worse, with your unsuspecting friends on board. The point at issue for me is not if, but when.
Any thoughts?
Any thoughts?
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I agree that incipient awarness is OK if low speed is the only way to get into a stall.
What about a violent change of direction to avoid another aircraft, flying through the jetwash of a mil jet or even inadvertant entry into IMC. all can result in a spin with little or no time to do anything about it.
Another thing is those unknown corners of the operating envelope.
A Grob115E will not actually stall in the classic sense (G break) when entered the normal way. It simply sits nose high with a high sink rate.
But leave power on, bank left or right and pull, leaves you with a spectacular and interesting full spin entry.
Of course it being a Grob if you release the controls it will return to its normal business of aviation almost as quick.
In the end it comes down to personal preference. I am glad I did spin training and refresh it every year with an instructor. I find it great fun, it seems to speeds up my reaction time and gives me more confidence in both what the aircraft and I can do when required.
What about a violent change of direction to avoid another aircraft, flying through the jetwash of a mil jet or even inadvertant entry into IMC. all can result in a spin with little or no time to do anything about it.
Another thing is those unknown corners of the operating envelope.
A Grob115E will not actually stall in the classic sense (G break) when entered the normal way. It simply sits nose high with a high sink rate.
But leave power on, bank left or right and pull, leaves you with a spectacular and interesting full spin entry.
Of course it being a Grob if you release the controls it will return to its normal business of aviation almost as quick.
In the end it comes down to personal preference. I am glad I did spin training and refresh it every year with an instructor. I find it great fun, it seems to speeds up my reaction time and gives me more confidence in both what the aircraft and I can do when required.
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Any thoughts?
Training later on makes sense to me, as it is easy to depart during avoiding action in the cruise and other scenarios.
Totally agree with the spiral dive recovery, since these are easy to get into and potentially destructive.
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Originally Posted by bjornhall
... which is your gust load margin. If you use up that for maneuvering and hit even a minor gust... 
The aircraft has posted limits - If it's certified to 4g, you fly no more than that *including* allowances for gusts. I.e. if it's bumpy you do not manouver at 4g. Anything over that is an overstress, and is treated as such.
Same goes for Vne. They're hard limits.
I don't know the logic behind the certification requirements, I may be able to make guesses, but I won't - I'm certain however that it's not to allow you a gust margin. Bear in mind that the aeroplane can be irrevocably bent and still pass the test. (oh, and I'm wrong, it's 3 seconds, not 30.
The scenario was that if you're in a whole heap of trouble, heading down fast (assume you're going to break something, and it's no longer possible to stay within the envelope), what is most appropriate?
I think the answer is probably that it depends on the aircraft - seems some aircraft are more artificially limited by things like local mach effects etc (e.g. mad_jock's ride), however others (particularly lower speed aircraft) are going to be limited by high speed aerodynamic effects like flutter. G induces drag, which is a good way of slowing things down. I'm not suggesting that any load is applied abruptly, or carelessly - as we all know, the faster you're going, the more capacity you have to overload the thing.
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I'm tempted to endorse, in all seriousness, Mad Jock and Lister Noble's suggestions about spinning in a glider...
... noting, though, that most of us aren't as mad as MJ suggests!
Until I'd spun a glider properly, and despite all the incipient spin training, I was always somewhat apprehensive of low-speed flight. No bad thing, perhaps, but it was a nagging niggle that I was much happier without. What counted for me was to do the full spinning exercises in an aircraft that positively required my recovery - most recent gliders will barely spin at all and recover more or less by themselves. So there was nothing over-ambitious or gung-ho about this; rather the opposite, and it made me a much happier pilot. Of course, it can also whet your appetite, and I subsequently enjoyed a happy summer of incompetent dual aeros while we had access to a suitable aircraft!
Spin training is a more regular part of training in gliding than in light aviation, so finding a club and instructors that can take you through the very well developed syllabus (including examples of 'non-aerobatic' entries) shouldn't be hard. My advice would be to find a club that can aerotow you to 4000' in an aircraft that will spin properly (the Puchacz is excellent). Gliders have more inertia in roll, so spinning isn't as rapid/violent as in light aircraft, though the idea's the same.
Oh, and definitely fly on a full stomach. I wouldn't necessarily go for a greasy full English, but a belly comfortably full of something settling definitely helps me!
Windrusher
And lister go and do some spinning in a glider its whole heap slower but they are mad bastards and do it bloody close to the ground and through clouds.
Glider ,great idea,I had a lesson last year at, Tibbenham which is half a mile for our airstrip and really enjoyed it.
Until I'd spun a glider properly, and despite all the incipient spin training, I was always somewhat apprehensive of low-speed flight. No bad thing, perhaps, but it was a nagging niggle that I was much happier without. What counted for me was to do the full spinning exercises in an aircraft that positively required my recovery - most recent gliders will barely spin at all and recover more or less by themselves. So there was nothing over-ambitious or gung-ho about this; rather the opposite, and it made me a much happier pilot. Of course, it can also whet your appetite, and I subsequently enjoyed a happy summer of incompetent dual aeros while we had access to a suitable aircraft!
Spin training is a more regular part of training in gliding than in light aviation, so finding a club and instructors that can take you through the very well developed syllabus (including examples of 'non-aerobatic' entries) shouldn't be hard. My advice would be to find a club that can aerotow you to 4000' in an aircraft that will spin properly (the Puchacz is excellent). Gliders have more inertia in roll, so spinning isn't as rapid/violent as in light aircraft, though the idea's the same.
Oh, and definitely fly on a full stomach. I wouldn't necessarily go for a greasy full English, but a belly comfortably full of something settling definitely helps me!
Windrusher
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I remember vividly an occasion I was flying an old wooden glider really slowly in a gusty thermal at about 1000ft and within an instant the thing was banked hard over standing on it's wingtip and the nose dropping below the horizon. The reaction to ease the stick forward and apply opposite rudder was instantaneous and instinctive. I have often wondered whether, without the benefit of experience, my first instinct in this sudden unexpected situation would have been to try pulling the nose back up and correct the roll with aileron.
But the real point is that the warning signs were there long before the unintended manoeuver occurred. I was flying very slowly, in a turn, in gusty air. My brain had already registered that it was the perfect recipe for a spin so I was subconciously already expecting it to happen. I just can't see how I could have gained that instinctive behavior without experiencing it over and over again.
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The scenario was that if you're in a whole heap of trouble, heading down fast (assume you're going to break something, and it's no longer possible to stay within the envelope), what is most appropriate?
Btw, there is a lot about gust loads and gust margins, at least in FAR 23 (and therefore, I suppose, in JAR 23...). Not sure about CAR 4 ... But I'd be interested in those 3 seconds at 50% overstress? I don't understand how you could design something against such a limit, nor how you'd show compliance... And my understanding is that the airframe should be able to withstand a 50% overstress indefinitely.
Reading, in detail, and fully understanding FAR 23 has been on my to do list for a long time... Maybe it's about time to do it!
But we might be straying off topic...
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Spinning.... Recommendations please.
Well in the northern hemisphere I'd spin to the left, In the southern hemisphere I'd spin to the right.....
There we go, thread back on track....
There we go, thread back on track....
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Windrush the more I see of the training of glider pilots the more professional I think it is compared to regulated instruction.
The incremental auth's for the instructors as they learn the art of instructing. Also how the student is gradually given more rope to allow them to make decisions as their experience progresses.
I have very few glider hours but I intend to resolve this issue this year. Anyway I owe the CFI of the Royal Deeside a slab of red for an Indiscretion in a powered fixed wing.
and it would be rude to drive all that way and not do the weeks gliding course.
The incremental auth's for the instructors as they learn the art of instructing. Also how the student is gradually given more rope to allow them to make decisions as their experience progresses.
I have very few glider hours but I intend to resolve this issue this year. Anyway I owe the CFI of the Royal Deeside a slab of red for an Indiscretion in a powered fixed wing.
and it would be rude to drive all that way and not do the weeks gliding course.
