Unusual Attitude recovery article - AOPA Flight Training Magazine

Jaybird180

Jaybird180

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Jaybird180
The October issue (http://flighttraining.aopa.org/magazine/2011/October/technique.html) has a suggested recovery technique that varies from what I was taught (or understood). I would like to get some feedback on the article.

First, the article recommends against using the AI for bank information and instead use the TC. My understanding of the limitation of the TC is that it will not show bank information and is only reliable if the aircraft's heading is changing, like in a turn.

The article also recommends adding power as recovery step 1 for a nose-high recovery. I reason that it is preferred to lower the AoA as the first step as you may be near a stall and in some cases power will aggravate an imminent stall.

What do you all think?
 
Jaybird180 said:
The October issue (http://flighttraining.aopa.org/magazine/2011/October/technique.html) has a suggested recovery technique that varies from what I was taught (or understood). I would like to get some feedback on the article.

First, the article recommends against using the AI for bank information and instead use the TC. My understanding of the limitation of the TC is that it will not show bank information and is only reliable if the aircraft's heading is changing, like in a turn.

The article also recommends adding power as recovery step 1 for a nose-high recovery. I reason that it is preferred to lower the AoA as the first step as you may be near a stall and in some cases power will aggravate an imminent stall.

What do you all think?
Click to expand...

Well...here's the thing...if all is working properly, the AI will give you the quickest, most straight-forward reference for correcting the bank. But the question is, how did you get into the unusual attitude in the first place? Was it because of a vacuum or other instrument failure and if not, and even if it wasn't, the unusual attitude may have been significant enough to tumble the AI. That is why they recommend the Turn Coordinator as primary. Personally, I was taught TC and x-refernece with Magnetic compass...yes, the TC won't show a bank unless you are turning, but keep in mind, you won't be turning if your wings are level.

On the Nose-high, add power issue, to be fair, they do say in step 2 to 'simultaneously' lower the nose, but I would agree with you. I would have said to lower the nose and simultaneously add power.
 
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If you're in VFR conditions - use the NH - Natural Horizon - it's a gazillion miles wide.

For IMC, though, unusual attitudes are deciphered using at least one gyro for bank, and airspeed and altitude for pitch. Using the TC is how you'd have to do it in a partial-panel situation, so it's VERY good to practice this. Frankly, the failure of the AI or the energy source powering it is likely to be how you got into the unusual attitude in the first place.

What I do is take a half second to sweep all the instruments in the six pack (or the glass equivalents), so that I can get an accurate picture of what's going on. When I know what's going on, I put in recovery inputs (power, pitch, roll) and monitor the instruments to ensure I get recovery.

If I'm nose high and low/decreasing energy I put in all the inputs together. If nose low/increasing energy I put in power and roll inputs and am very gentle with pitch inputs until the wings are level and the airspeed is reasonable.

For homework, look up the difference between a turn coordinator and the instrument that preceded it, commonly (and misleadingly) called a turn-and-bank. Then come back and explain what you've learned and how it applies to unusual attitude recovery. Wikipedia will suffice.

I love being a teacher.
 
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TMetzinger said:
If you're in VFR conditions - use the NH - Natural Horizon - it's a gazillion miles wide.

For IMC, though, unusual attitudes are deciphered using at least one gyro for bank, and airspeed and altitude for pitch. Using the TC is how you'd have to do it in a partial-panel situation, so it's VERY good to practice this. Frankly, the failure of the AI or the energy source powering it is likely to be how you got into the unusual attitude in the first place.

What I do is take a half second to sweep all the instruments in the six pack (or the glass equivalents), so that I can get an accurate picture of what's going on. When I know what's going on, I put in recovery inputs (power, pitch, roll) and monitor the instruments to ensure I get recovery.

If I'm nose high and low/decreasing energy I put in all the inputs together. If nose low/increasing energy I put in power and roll inputs and am very gentle with pitch inputs until the wings are level and the airspeed is reasonable.

For homework, look up the difference between a turn coordinator and the instrument that preceded it, commonly (and misleadingly) called a turn-and-bank. Then come back and explain what you've learned and how it applies to unusual attitude recovery. Wikipedia will suffice.

I love being a teacher.
Click to expand...

Also the TC is the one gyro instrument that can't tumble. If it's operational and not flagged, it is the one that should be trusted if there is a conflict.
 
The Difference is if you are flying VMC or IMC. IF you are in an unusual attitude because you have lost your visual references, which can be fairly easy to do at night then use the Attitude indicator.

If you were using the Attitude indicator and are now in an unusual attitude then use the Turn Coordinator, since it is likely the reason you are in the unusual attitude is because the AI has failed.

I teach student pilots to use the AI, instrument pilots to use the Turn Coordinator.
I am currently flying with a student pilot that has only a Turn and Bank for a Gyro, this does make unusual attitude recovery a bit more interesting.

Brian
CFIIG/ASEL
 
When I took my training we were taught to use the TC rather than the AI for reference along with the ASI and altimeter.

The instructor would get you to look down as he put the plane into either a spin, spiral dive or a stall.

The indicators for the spin were ASI moderately increasing, TC showing direction of yaw and altimeter rapidly decreasing.

Spiral dive was ASI rapidly increasing, TC direction of spiral, and altimeter rapidly decreasing.

The stall was pretty obvious of course.

It was hard to tell the difference between the spin and spiral dive under the hood.
The reason for using the TC was it was the least likely gyro to tumble.
 
TMetzinger said:
For homework, look up the difference between a turn coordinator and the instrument that preceded it, commonly (and misleadingly) called a turn-and-bank. Then come back and explain what you've learned and how it applies to unusual attitude recovery. Wikipedia will suffice.
Click to expand...
Apparently I never got all of the information about how useful the TC can be:mad:.

The difference between the two instruments is the TC can show roll information, which can then translate into a horizontal lift component (a turn).

TnB cannot display roll because it's gyro is fixed only about the vertical axis.
 
The techniques in that article are identical to those in Peter Dogan's Instrument Flight Training Manual and those we teach at PIC.

As for the question of what to do first in a nose-high recovery (add power or reduce AOA), since it only takes one hand for each, there's no reason not to do both at the same time. That said, power will not "aggravate an imminent stall" unless you let the application of power cause a sharp yaw due to failure to use your feet properly, too.
 
In my world an unusual attitude also implies the airplane is already uncoordinated which is why my process is power secondary.

It also jives with all I've heard about AoA being sufficient to break a stall. I have plans to do some experimentation with stalls in a Citabria soon, and will be able to see what ideas pan out for my understanding. I also intend to let them develop into spins for learning purposes.
 
Jaybird180 said:
Apparently I never got all of the information about how useful the TC can be:mad:.

The difference between the two instruments is the TC can show roll information, which can then translate into a horizontal lift component (a turn).

TnB cannot display roll because it's gyro is fixed only about the vertical axis.
Click to expand...
Neither (T&B or TC) displays bank angle. The T&B indicates rate of turn and the TC combines the rate of roll with the rate of turn. IME the "newer" TC can be misleading and/or confusing in a significantly abnormal attitude because of it's summed response. For instance if you're in a steep left bank and turning left and roll rapidly to the right, the TC will indicate a turn to the right while you're still turning left. The TC wasn't developed to improve on the T&B it was implemented to reduce overcontrolling in early autopilot designs that used a T&B. Since it includes roll rate the autopilot can apply aileron in response to a turbulence induced roll before a turn develops. This is a problem for autopilots because they don't coordinate turns unless they have a 3rd (yaw) axis so any adverse yaw tendency causes the T&B to show a right turn when the autopilot tries to roll left.
 
Thus why my Cessna 300 autopilot sucks. ;) Anyone who's flown behind one knows the limitations of a TC first-hand. It's excellent at S-turns along a course. ;)
 
Pardon me, 200 series. The 300 has a heading bug on the DG, which is it's most useful mode. ;)
 
gismo said:
Neither (T&B or TC) displays bank angle. The T&B indicates rate of turn and the TC combines the rate of roll with the rate of turn. IME the "newer" TC can be misleading and/or confusing in a significantly abnormal attitude because of it's summed response. For instance if you're in a steep left bank and turning left and roll rapidly to the right, the TC will indicate a turn to the right while you're still turning left. The TC wasn't developed to improve on the T&B it was implemented to reduce overcontrolling in early autopilot designs that used a T&B. Since it includes roll rate the autopilot can apply aileron in response to a turbulence induced roll before a turn develops. This is a problem for autopilots because they don't coordinate turns unless they have a 3rd (yaw) axis so any adverse yaw tendency causes the T&B to show a right turn when the autopilot tries to roll left.
Click to expand...

All true. But in an unusual attitude, the roll information is useful for recovery.

Sent from my ADR6300 using Tapatalk
 
TMetzinger said:
All true. But in an unusual attitude, the roll information is useful for recovery.
Click to expand...
...as long as you've practiced it in your plane and know just how far past "level" the TC will be when the wings are really level given the roll rate you achieve in that plane while doing that sort of recovery. My experience teaching that is that typically, you have to wait until the TC shows about 1/4-1/2 standard rate the other way before stopping the roll, at which point the TC will swing back to the zero-rate position indicating wings-level if the ball is centered (as long as your airplane isn't bent).
 
Ron Levy said:
...as long as you've practiced it in your plane and know just how far past "level" the TC will be when the wings are really level given the roll rate you achieve in that plane while doing that sort of recovery. My experience teaching that is that typically, you have to wait until the TC shows about 1/4-1/2 standard rate the other way before stopping the roll, at which point the TC will swing back to the zero-rate position indicating wings-level if the ball is centered (as long as your airplane isn't bent).
Click to expand...

Yep. I remember doing it in steps before I let it overshoot. Would go from 30 to 10 to 5 to level. Even with that issue though, the TC gives you good information on what control inputs are needed to recover, just not how much and when to stop.

A similar thing happens in pitch... it generally takes a couple of reducing excursions until the airplane is level in pitch, without an AI.
 
gismo said:
The old AN style (ribbon) will tumble if you go inverted. AFaIK most if not all of the vertical card types will not tumble.
Click to expand...

I've witnessed them tumble in an incipient spin. (half turn or whatever) Also one of our club 152's had one that was kinda worn out, it worked but it precessed quite a bit. It would tumble in a 60 degree bank.
 
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TMetzinger said:
A similar thing happens in pitch... it generally takes a couple of reducing excursions until the airplane is level in pitch, without an AI.
Click to expand...
If you follow Dogan's recommendation to use altimeter movement (or, rather, stoppage of altimeter movement) as the cue to stop changing pitch, you'll see a dramatic reduction in those excursions.
 
Is there a good reference for partial panel techniques for VFR pilots?
 
dell30rb said:
I've witnessed them tumble in an incipient spin. (half turn or whatever) Also one of our club 152's had one that was kinda worn out, it worked but it precessed quite a bit. It would tumble in a 60 degree bank.
Click to expand...
Typically, modern AI's are good to at least 55 degrees of pitch and 110 degrees of bank before tumbling. If it tumbles in a 60-degree bank, it's ready for overhaul, maybe more than ready. OTOH, if it tumbles in a spin, you can't blame the AI. Of course, doing spins isn't good for those non-cageable AI's (or heading gyros, either), so consider removing it temporarily for spin training. At the flight school I worked for 30-some years ago, the boss removed the AI/HI from one of our 12-15 C-150's and designated it the spin trainer, and limited it to traffic pattern only if flown solo by a Student Pilot.
 
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Ron Levy said:
Typically, modern AI's are good to at least 55 degrees of pitch and 110 degrees of bank before tumbling. If it tumbles in a 60-degree bank, it's ready for overhaul, maybe more than ready. OTOH, if it tumbles in a spin, you can't blame the AI. Of course, doing spins isn't good for those non-cageable AI's (or heading gyros, either), so consider removing it temporarily for spin training. At the flight school I worked for 30-some years ago, the boss removed the AI/HI from one of our 12-15 C-150's and designated it the spin trainer, and limited it to traffic pattern only if flown solo by a Student Pilot.
Click to expand...
I thought we were talking about DGs not AIs.
 
Ron Levy said:
If you follow Dogan's recommendation to use altimeter movement (or, rather, stoppage of altimeter movement) as the cue to stop changing pitch, you'll see a dramatic reduction in those excursions.
Click to expand...
I like to monitor the rate of altimeter movement. If you match your elevator inputs to that (relatively big control movement when the altimeter is moving quickly and small to tiny movements when it slows down) things seem to go rather smoothly. Is this what Dogan recommends, or something different?
 
Ron Levy said:
...as long as you've practiced it in your plane and know just how far past "level" the TC will be when the wings are really level given the roll rate you achieve in that plane while doing that sort of recovery. My experience teaching that is that typically, you have to wait until the TC shows about 1/4-1/2 standard rate the other way before stopping the roll, at which point the TC will swing back to the zero-rate position indicating wings-level if the ball is centered (as long as your airplane isn't bent).
Click to expand...
I didn't mean to imply that you can't recover UA with a TC, just that IME it's easier with a T&B because when the needle heads towards zero turn you can ease off the ailerons and end up level without factoring any offsets. And if you're recovering in actual IMC with accompanying turbulence and stress, I think it can make a difference.
 
Ron Levy said:
Typically, modern AI's are good to at least 55 degrees of pitch and 110 degrees of bank before tumbling. If it tumbles in a 60-degree bank, it's ready for overhaul, maybe more than ready. OTOH, if it tumbles in a spin, you can't blame the AI. Of course, doing spins isn't good for those non-cageable AI's (or heading gyros, either), so consider removing it temporarily for spin training. At the flight school I worked for 30-some years ago, the boss removed the AI/HI from one of our 12-15 C-150's and designated it the spin trainer, and limited it to traffic pattern only if flown solo by a Student Pilot.
Click to expand...

I should have been more specific.. I was talking about a vertical card DG.


And as for it hurting the gyros, I have heard that spinning does hurt them, and then I also read this article that says it does not hurt them. Scroll to bottom.



http://www.richstowell.com/documents/12StallSpinMyths.pdf
 
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Ron Levy said:
If you follow Dogan's recommendation to use altimeter movement (or, rather, stoppage of altimeter movement) as the cue to stop changing pitch, you'll see a dramatic reduction in those excursions.
Click to expand...

I do, and they ARE reduced, but NOT eliminated.
 
gismo said:
I didn't mean to imply that you can't recover UA with a TC, just that IME it's easier with a T&B because when the needle heads towards zero turn you can ease off the ailerons and end up level without factoring any offsets. And if you're recovering in actual IMC with accompanying turbulence and stress, I think it can make a difference.
Click to expand...

I'm not sure I understand this, but I've never flown with a T-n-B. I was under the impression that a TC was "better" for UA recovery.
 
gismo said:
I like to monitor the rate of altimeter movement. If you match your elevator inputs to that (relatively big control movement when the altimeter is moving quickly and small to tiny movements when it slows down) things seem to go rather smoothly. Is this what Dogan recommends, or something different?
Click to expand...
That's pretty much it.
 
gismo said:
I didn't mean to imply that you can't recover UA with a TC, just that IME it's easier with a T&B because when the needle heads towards zero turn you can ease off the ailerons and end up level without factoring any offsets.
Click to expand...
Concur completely. But while it's easier with a T&B, it isn't all that difficult with a TC.
 
Ron Levy said:
Concur completely. But while it's easier with a T&B, it isn't all that difficult with a TC.
Click to expand...
Hmm... With a T&B, same technique for bank as you use with the altimeter for pitch?

As the needle deflection reduces, reduce your correction until you and the needle are both stopped?
 
Ron Levy said:
If you follow Dogan's recommendation to use altimeter movement (or, rather, stoppage of altimeter movement) as the cue to stop changing pitch, you'll see a dramatic reduction in those excursions.
Click to expand...

My instrument instructor had me using Dogan's book, but he taught me that when the VSI needle changes its direction of movement (i.e., stops going up and starts going down, or vice versa), that's level attitude, and he had me use that for pitch control when partial panel. I would be surprised if that statement were completely accurate, but the technique seems to work well in practice.
 
Palmpilot said:
My instrument instructor had me using Dogan's book, but he taught me that when the VSI needle changes its direction of movement (i.e., stops going up and starts going down, or vice versa), that's level attitude, and he had me use that for pitch control when partial panel. I would be surprised if that statement were completely accurate, but the technique seems to work well in practice.
Click to expand...
Due to the lag inherent in a regular VSI, I've found that method is counterproductive. Of course, if you have an IVSI (instantaneous VSI), that's another story. But I've seen a lot of yo-yo'ing in both partial panel UA recoveries and in instrument steep turns when folks try to use the VSI instead of the much more rapidly responding altimeter.

OTOH, just as with using the TC for roll, with practice in that aircraft, you can probably learn to read the lag in response and still get the job done neatly. I just think it's a lot easier to use the altimeter (just as it's easier using a T&B than a TC). And while YMMV, I'm suggesting this because my trainees seem to get the task nailed down faster using the altimeter. The difference between this and the TC issue is that not many airplanes have both a TC and a T&B, so you usually get no choice there, but they've pretty much all got both altimeter and VSI, so you do have a choice in that axis.
 
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Ron Levy said:
Due to the lag inherent in a regular VSI, I've found that method is counterproductive. Of course, if you have an IVSI (instantaneous VSI), that's another story. But I've seen a lot of yo-yo'ing in both partial panel UA recoveries and in instrument steep turns when folks try to use the VSI instead of the much more rapidly responding altimeter.
Click to expand...

I was taught the method I described as a way of compensating for the lag. The VSI needle changes its direction of movement a lot sooner than it passes through zero. I haven't noticed a problem with yo-yoing, and if the various instrument instructors I've flown with noticed a problem, they haven't said anything.

So, just to clarify, when leveling off, I don't wait for the VSI needle to reach zero before I stop adjusting the pitch. I stop adjusting the pitch as soon as the needle changes its direction of movement, and then wait and see what I end up with before making further adjustments. If further adjustments are required, my recollection is that they are small.

OTOH, just as with using the TC for roll, with practice in that aircraft, you can probably learn to read the lag in response and still get the job done neatly. I just think it's a lot easier to use the altimeter (just as it's easier using a T&B than a TC). And while YMMV, I'm suggesting this because my trainees seem to get the task nailed down faster using the altimeter. The difference between this and the TC issue is that not many airplanes have both a TC and a T&B, so you usually get no choice there, but they've pretty much all got both altimeter and VSI, so you do have a choice in that axis.
Click to expand...

I can't comment on which is easier, since I've only done it the way I was taught.
 
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I have taken unusual attitude recovery training (in a Decathlon). For the nose-high recovery, I was taught to go full power and roll knife-edge. By rolling knife edge you can unload the wings (reduce AoA) and the nose will fall through the horizon which is what you want. Once you have some speed built up you roll horizontal and recover. The rationale for going knife-edge is that you won't incur any large negative-g loads by pushing over with the elevator. This may be important in aircraft that don't have inverted fuel and oil capability.
 
jstro said:
I have taken unusual attitude recovery training (in a Decathlon). For the nose-high recovery, I was taught to go full power and roll knife-edge. By rolling knife edge you can unload the wings (reduce AoA) and the nose will fall through the horizon which is what you want. Once you have some speed built up you roll horizontal and recover. The rationale for going knife-edge is that you won't incur any large negative-g loads by pushing over with the elevator. This may be important in aircraft that don't have inverted fuel and oil capability.
Click to expand...
That might be a good technique with solid external visual references in an aerobatic aircraft, but increasing bank in an unusual attitude when on the instruments in a partial panel situation isn't what you'd want to do. As for doing that on instruments with an operable AI in a typical light GA airplane, I'm not real sure either way.
 
Palmpilot said:
My instrument instructor had me using Dogan's book, but he taught me that when the VSI needle changes its direction of movement (i.e., stops going up and starts going down, or vice versa), that's level attitude, and he had me use that for pitch control when partial panel. I would be surprised if that statement were completely accurate, but the technique seems to work well in practice.
Click to expand...

BTW, I found a Web site that describes this method in the context of partial panel unusual attitude recovery.

Partial Panel Recovery
1. Check VSI
If climbing, lower nose to reverse trend
Use turn coordinator and level wings

2. Check VSI
If descending, check turn coordinator and level wings
Raise nose until VSI trend reverses.​

http://whitts.alioth.net/Pageg31 IFR Procedures.htm
 
I discovered how to use the VSI as a primary pitch instrument when I learned helicopter instruments.

In helicopters, the AI isn't a good reference as to the pitch of the wing, so we learned to use the VSI just as Palm Pilot describes it, and it is definitely a much better immediate indicator of pitch for airplanes too.

This technique is described in the FAA Instrument flying Handbook, but only in the Chapter on helicopter instruments.

But the principle and technique is just as useful in the airplane. I have used and taught this technique for years. And yes, as Ron says, the technique takes a while longer to master, because you are having to learn to read and lead the VSI needle, but the pay off is worth it. Also, it is much easier to start off an instrument student with this technique than it is to teach a more experienced pilot who already has a scan/react habit pattern.

But really, the vsi and altimeter start moving, starting slowing, stopping, reversing, all at the same time. They are pressure instruments reacting exactly the same, the BIG difference is that the vsi needle makes a RELATIVELY BIGGER movement which is easier for the beginning instrument reader to see and feel a control response to.

The Altimeter tells me WHAT to do; the VSI tells me HOW MUCH to do it.
 
nosehair said:
I discovered how to use the VSI as a primary pitch instrument when I learned helicopter instruments.

In helicopters, the AI isn't a good reference as to the pitch of the wing, so we learned to use the VSI just as Palm Pilot describes it, and it is definitely a much better immediate indicator of pitch for airplanes too.

This technique is described in the FAA Instrument flying Handbook, but only in the Chapter on helicopter instruments.

But the principle and technique is just as useful in the airplane. I have used and taught this technique for years. And yes, as Ron says, the technique takes a while longer to master, because you are having to learn to read and lead the VSI needle, but the pay off is worth it. Also, it is much easier to start off an instrument student with this technique than it is to teach a more experienced pilot who already has a scan/react habit pattern.

But really, the vsi and altimeter start moving, starting slowing, stopping, reversing, all at the same time. They are pressure instruments reacting exactly the same, the BIG difference is that the vsi needle makes a RELATIVELY BIGGER movement which is easier for the beginning instrument reader to see and feel a control response to.

The Altimeter tells me WHAT to do; the VSI tells me HOW MUCH to do it.
Click to expand...

I like
 
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