Unusual attitude recovery?
Thread Starter
Unusual attitude recovery?
A friend of mine - who is a fixed wing and gyrocopter pilot, but not heli - sent me the following question:
I was wondering, what's the standard procedure to recover from a nose-high attitude in a helicopter (in IMC)? How do you even recognize it (without an AI)? I've googled it briefly and ended up in a hole of contrasting opinions.
So here's my reply:
Honestly I have no idea. I've never practised unusual attitudes in a heli. For sure (in a Robbo) rolling into a knife edge doesn't strike me as a great idea, which is the fixed wing answer. If it was nose-high (not vertical) I guess I'd GENTLY push the cyclic forward, and GENTLY drop the collective, and see what happens.
Someone here must know the "right" answer...
I was wondering, what's the standard procedure to recover from a nose-high attitude in a helicopter (in IMC)? How do you even recognize it (without an AI)? I've googled it briefly and ended up in a hole of contrasting opinions.
So here's my reply:
Honestly I have no idea. I've never practised unusual attitudes in a heli. For sure (in a Robbo) rolling into a knife edge doesn't strike me as a great idea, which is the fixed wing answer. If it was nose-high (not vertical) I guess I'd GENTLY push the cyclic forward, and GENTLY drop the collective, and see what happens.
Someone here must know the "right" answer...
Thread Starter
Well, yeah, I agree with that bit - I should have redacted that bit since he was just kidding there. But my original question remains - if for whatever reason you do find yourselves pointing skywards at 45 or 60 degrees, what do you do to recover?
Well, helicopters don‘t like to fly nose up high anyway....
To get the nose anywhere near the horizon you need to attach horizontal stabilzers to the taiboom, which are upside down airofoils, pushing the tail down to raise the nose....
😜😜😜😜😜😜😜😜
Never flown in IMC without an AI
With modern helicopters, just press the „Maria HELP-button“, the AP will take over with IAS, ALT and HDG 😉
To get the nose anywhere near the horizon you need to attach horizontal stabilzers to the taiboom, which are upside down airofoils, pushing the tail down to raise the nose....
😜😜😜😜😜😜😜😜
Never flown in IMC without an AI
With modern helicopters, just press the „Maria HELP-button“, the AP will take over with IAS, ALT and HDG 😉
Power Setting? AKA....Collective Setting? Vertical Speed?
There are a few factors that bear on the outcome of the situation....AI or no AI.
One can wind up on basic instruments with no surface reference for various reasons....besides pure dumbass.
There are a few factors that bear on the outcome of the situation....AI or no AI.
One can wind up on basic instruments with no surface reference for various reasons....besides pure dumbass.
(even if it is disigned to raise the nose normally)
Reminds me about fun in the Navy...
Was quite cool on the Lynx, flying backwards at higher speeds and then just giving a notch nose down - getting the bird into pointing vertical down 😉
This is kind of a stupid scenario. Okay, so if you lower the nose, how much do you lower it and how do you know when it's enough? If you're in IMC in a helicopter without an AI you're basically dead. So don't worry about it is what I'm saying. Just freeze the controls.
It'll be over quick anyway.
It'll be over quick anyway.
Thread Starter
Please guys, I did already say to ignore the bit about IMC and the AI. I'masking a serious question. In perfect day VFR conditions, you hit wake turbulence (let's say) and suddenly find yourself pointing skywards - as determined by looking out of the window. Now what do you do?
As far as fixed wing goes, when I did my unusual attitude training (VFR), yes, if you're 60 degrees nose up, roll into a knife edge, wait for the nose to drop to near horizontal, roll back out of the knife edge. Works perfectly, in any airplane (doesn't need to be aerobatic although of course to be legal you should only be practising in an aerobatic aircraft). Otherwise you're likely to run out of airspeed. That will resolve itself SOMEHOW, but could well get you into a situation where the recovery is trickier than the above.
Seems to me that a heli will thoroughly dislike that attitude anyway, since the CG will be so far displaced (horizontally) from the centre of lift. So maybe it's a non issue and (if you could figure out how to get there in the first place) it would just sort itself out.
As far as fixed wing goes, when I did my unusual attitude training (VFR), yes, if you're 60 degrees nose up, roll into a knife edge, wait for the nose to drop to near horizontal, roll back out of the knife edge. Works perfectly, in any airplane (doesn't need to be aerobatic although of course to be legal you should only be practising in an aerobatic aircraft). Otherwise you're likely to run out of airspeed. That will resolve itself SOMEHOW, but could well get you into a situation where the recovery is trickier than the above.
Seems to me that a heli will thoroughly dislike that attitude anyway, since the CG will be so far displaced (horizontally) from the centre of lift. So maybe it's a non issue and (if you could figure out how to get there in the first place) it would just sort itself out.
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Maybe you are expecting a more complicated answer to your question but it was already answered here and it is a very simple thing to do, just push the the nose forward (cyclic forward) but I would apply a little bit of power at the same time, you don't want to end up in mast bumping, keep the disk loaded in that case.
Depending on the situation, a pedal turn could be an option as well.
JD
Depending on the situation, a pedal turn could be an option as well.
JD
Last edited by fijdor; 5th Oct 2017 at 00:13.
In my basic training, after a low run across the paddock, the instructor put the 300 somewhere past 60º and when the speed decayed applied 'rudder' (aka, pedal turn) thus giving a nice 180º turn for the next low run across the paddock. I woulda thought this were part of every heli pilot training?
Couple of years back i had a National Parks chap on board and he pointed out where that Skyhooks singer pranged. I remember thinking of the irony of the sky hook name - no hook that day. Relavence here is there were a lotta comment around pilot circles of possible unusual attitude recovery technics.
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Last edited by Flying Binghi; 5th Oct 2017 at 00:44.
Interesting video posted on YouTube on Pilot Yellow's channel... He runs a helicopter flight school in BC, Canada. He and another pilot went out in a Cabri and did some flying where the PF could not see outside. He (as the PNF) monitored and kept everything with the spinny side up but is a VERY enlightening video!!!
As a military pilot, and instrument flight examiner, I suppose I had made some assumptions. Our flight task for inadvertent IMC, and unusual attitudes are very similar. They are obviously very different situations, but one can quickly become the other. The immediate action steps are, in this order... attitude, heading, torque, airspeed, trim(yaw). Attitude, set the aircraft to a level attitude in both pitch and roll. Heading, use your current heading and only induce a turn to avoid known obstacles. Torque, set the torque or power for hover, climb, or cruise (based on conditions/ airspeed). Airspeed, select and maintain an airspeed, if IMC, best endurance is a good starting point (50-80knots depending on type)... and finally Trim, verify the ball is centered. I could have an entire evening conversation on the subject, each type requires specific adjustments based on aircraft performance, but this should be enough to go in the right direction. Airplanes require certain actions to maintain airspeed energy, nose high add power, nose low reduce power. Helicopters don't needed as much focus on that energy except in the most extreme conditions.typically levelling the aircraft and applying hover power will be enough to buy me a few seconds. So, basic aircraft control is at the forefront of this task. I sincerely hope this helps
In perfect day VFR conditions, you hit wake turbulence (let's say) and suddenly find yourself pointing skywards - as determined by looking out of the window. Now what do you do?
If you are VFR and hit enough wake (or other) turbulence to suddenly put you 60 degrees nose up, you have probably overstressed the aircraft (especially something small like R22) and major structural failure is likely.
A sudden snap to 60 degrees nose up from cruise speed is about a 4 to 5g pull, perhaps more.
And, in a teetering head helo, your natural reaction will be to push forwards with the cyclic, probably inducing mast bumping as the g reduces and the probability of MR to tail boom contact.
If your chum actually wants to know how to do wingovers and pedal turns in a helicopter, that is a different conversation.
Flying Bull - with you on having fun in the Lynx
A sudden snap to 60 degrees nose up from cruise speed is about a 4 to 5g pull, perhaps more.
And, in a teetering head helo, your natural reaction will be to push forwards with the cyclic, probably inducing mast bumping as the g reduces and the probability of MR to tail boom contact.
If your chum actually wants to know how to do wingovers and pedal turns in a helicopter, that is a different conversation.
Flying Bull - with you on having fun in the Lynx
In every school in which I instructed, we taught the students to deal with UAs. In day VFR, turn it into a wingover, or rotorover, by rolling to whichever side is favoured, keep gentle back pressure in until the nose is almost back to the horizon, then roll wings level - but on a different heading. Once it is all stable, turn back to where you want to go.
In IMC (in an IFR aircraft) in a teetering head machine, if the wings are nearly level but nose is high, gently lower the nose while applying a small amount of collective to load the disc. If the wings are not level, or airspeed is rapidly dropping, use same as day VFR, a gentle turn with back pressure, let the nose come down, roll level.
In IMC (in an IFR aircraft) in a teetering head machine, if the wings are nearly level but nose is high, gently lower the nose while applying a small amount of collective to load the disc. If the wings are not level, or airspeed is rapidly dropping, use same as day VFR, a gentle turn with back pressure, let the nose come down, roll level.
AC - I agree with everything else in your post but this
is almost certainly likely to result in further disorientation and a worsening of the UA.
Turning and acceleration errors are what cause the leans and often lead to the UA - get the wings level first, adjust the attitude to control the speed and add/subtract power as required.
WASP - as mentioned earlier by Letsby, is the standard recovery (with some small variations in terminology) for all 3 Brit Mil services.
All of the above needs to be done positively but gently since many pilots aggravate the UA by being too 'punchy' with their recovery technique.
If the wings are not level, or airspeed is rapidly dropping, use same as day VFR, a gentle turn with back pressure, let the nose come down, roll level
Turning and acceleration errors are what cause the leans and often lead to the UA - get the wings level first, adjust the attitude to control the speed and add/subtract power as required.
WASP - as mentioned earlier by Letsby, is the standard recovery (with some small variations in terminology) for all 3 Brit Mil services.
All of the above needs to be done positively but gently since many pilots aggravate the UA by being too 'punchy' with their recovery technique.
Pretty simple - just gently ease the nose to the closest horizon, set around hover power with collective and keep it straight with pedal.
Don't slam the cyclic forward, just go gently and mast bump won't be an issue.
Don't slam the cyclic forward, just go gently and mast bump won't be an issue.