Upset Prevention and Recovery

[jlunseth]

This is mandatory reading: https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_120-109A.pdf

Its the regulatory body prose version of what we learned to do in real time.

[Hank]

2 hours ago, jlunseth said:

The only thing I didn't change was the statement about flying out of a stall, which can make the stall more difficult to resolve. Example, Air France 447. They may have eventually made it into a spin, I don't know, but it was pulling and attempting to power out of a stall that caused the problem (according to the reports). The right answer is PUSH.

I thought 447's problem was one pilot apply FULL UP stick, the other properly apply FULL DOWN, with no connection between their little joysticks to know what the other person was doing . . . In a Boeing [or other plane with real yokes], it would have been obvious, and a swift punch would have made the one pulling let go. Never have figured out why, when the IAS is too low, some people pull.

[jlunseth]

I think the issue with the controls was that the sticks are not connected in the Airbus, so the pilot not flying (PNF) does not see what the pilot flying(PF) is actually doing, in other words, the PF had the stick full back and the other stick just sits there doing nothing.  With linked controls, like those in our Mooney, the PNF would have the yoke in his lap, and would know.  

Watch this: 

 

Edited January 31, 2020 by jlunseth

[Volare]

With linked controls in a Boeing that is true to a point. As we saw in the Atlas Air crash in Houston, one pilot PUSHED so hard that he put the plane in a nose down attitude that was unrecoverable. The Captain sheered the control interconnect trying to PULL to overpower him.

Edited February 1, 2020 by Volare

[Denver98]

The controls in Airbus equipment are “summed”, meaning a full up stick on one side and a full down stick on the other equals ZERO pitch change.  There is also an aural alert “dual input” so the pilots know that they are both trying to fly the airplane.  447 was in alternate law meaning they had multiple failures of redundant systems.  That is what allowed them to stall the airplane.   The crew, sadly, allowed an airplane capable of flying to remain in a stall and it had nothing to do with lack of a control interconnect.  I’ve said it before, I prefer the Airbus fly-by-wire philosophy without question, over the Boeing fly-by-wire philosophy.  

[PT20J]

15 hours ago, Denver98 said:

The controls in Airbus equipment are “summed”, meaning a full up stick on one side and a full down stick on the other equals ZERO pitch change.  There is also an aural alert “dual input” so the pilots know that they are both trying to fly the airplane.  447 was in alternate law meaning they had multiple failures of redundant systems.  That is what allowed them to stall the airplane.   The crew, sadly, allowed an airplane capable of flying to remain in a stall and it had nothing to do with lack of a control interconnect.  I’ve said it before, I prefer the Airbus fly-by-wire philosophy without question, over the Boeing fly-by-wire philosophy.  

How to “connect” two mechanically unconnected side sticks so that it is unambiguous which pilot has control was apparently an area of much concern to pilots that reviewed the early Airbus design. Urs Ribi was a Swissair captain on the team that consulted on this. He told me that the original proposed design was that only one stick would have control and the pilot with the stick not in control could switch control by moving the stick full travel in any direction. Urs told me he looked the engineer square in the eye and said matter of factly, “No pilot would ever do that.”

Skip

[PT20J]

On 1/31/2020 at 8:22 AM, jlunseth said:

You are correct, in 4 & 5 I was talking about incipient and developed spins, not stalls.  Thank you for catching that.  I think my head is still spinning. I made the changes (I hope).  The only thing I didn't change was the statement about flying out of a stall, which can make the stall more difficult to resolve. Example, Air France 447. They may have eventually made it into a spin, I don't know, but it was pulling and attempting to power out of a stall that caused the problem (according to the reports). The right answer is PUSH.

Lest anyone think a 447 type accident is an Airbus problem and Boeings are immune:

https://lessonslearned.faa.gov/Birgenair301/NWA6231_Accident_Report.pdf

Don’t forget your pitot heat. 

[jlunseth]

I figured out how to cut the video.  These are two full stalls.  The first is a slipping stall. The instructor is on the controls and although you can see my hand on the stick, I am just following along.  I got my turn at it, but his slipping stall was the best of them.  The set up is a little nose high, engine to idle, you will see the ball slide toward the low wing (Ball low, good to go).  It takes a little to get the aircraft to stall, by which I mean we were holding in both pitch and bank and the stick would get mushy as the stall neared.  There was a very distinct buffet.  But as you will see, the stall is dynamic, the aircraft inverts.  In my first few attempts I was instinctively reluctant to hold in the pitch, but I got good enough at it eventually that we had to work on which way to roll during the recovery, in other words, the aircraft would roll slightly past 180 inverted and the quicker roll out was in the direction of the stall roll.  So much for the easy slipping stalls.  What I will say about them is that we pulled the engine to idle and there was quite a bit of warning, buffet, mushy controls, and you would hear the stall warning.

The second is the skidding stall with me flying.  We had power in to simulate the base to final turn.  Bank to 30 degrees (this is my first effort and you will see a little overbank, and some tendency to let the pitch drop). Then put in rudder to make the turn tighter......and bam, the aircraft would invert.  Ball high you die. The skidding stall provides almost no warning.  We got a very slight buffet, as I said earlier more like an engine shudder.

Comparing the two, the slipping stall and the skidding stall, at least in the Extra, there is definitely more warning and it is harder to get the plane to stall in the slip, but when it goes it is more violent than the skid.  Little or no warning for the skid and plenty of drama.

The recovery we used was not the P.A.R.E. recovery, it was PUSH ROLL POWER STABILIZE.  

We also did accelerated stalls, straight ahead stalls, they are just not as dramatic as what you will see in these videos.

Let me know if the video is working ok, it is in m4v format, which is an MP4 format, just the more current one.  I can put them in MP4 I think. 

Now I am going to try to put up an upright spin and an inverted spin.  Carusoam wanted something wooly.

Edited February 5, 2020 by jlunseth

[jlunseth]

One more slipping stall, just in case anyone is tempted to think they are mild.  As I said, I got better at holding pitch, so the stall fully inverts. It would have been quicker to keep rolling in the direction of the stall to get out.

[jlunseth]

This is an incipient spin. An incipient spin is one where the aircraft is in the first turn of the spin. In this case I was at the controls and we used a skidding stall to get into it.  Then I was not allowed to recover until the instructor said "Recover." The recovery was PUSH ROLL POWER STABILIZE, not the P.A.R.E. recovery.  You can see that it works fine.  Our Mooneys are only certified to one turn.

[jlunseth]

Spins.

The first one is a full upright spin.  The instructor put the aircraft into a developed spin and then had me recover.  I tried the PUSH ROLL etc. first and that had no effect, so did Power (Idle) Ailerson (Neutral) Rudder (Opposite the spin) Elevator (Push), then rudder to neutral and elevator back to pull out of the dive.

The second one is a full inverted spin, just for those who want something wooly.  If you want more wooly than that, I have one other one I can put up if anyone wants to see it, about a ten turn spin or something like that.  It is a demonstration of inputs that don't work.  Power lifts the nose and increases the spin, ailerons one way will slow the spin a little, the other way will increase it, but they do not break it, elevator does not break it, it requires the P.A.R.E. at that point, and then a little level flight so pilot's gyros return.  Turns your internal gyros pretty good. Let me know if you want to see it.

[skydvrboy]

Thanks for the videos!   They really provide context to your earlier descriptions.

[jlunseth]

I got home and looked at these on my iPad.  They all worked except the last one, the inverted spin.  Is that one working for everyone, if not I have got this figured out now and it would be easy to put up a new video tomorrow.

PS I tried it again and it worked fine, let me know if there are problems.

Lastly, don’t try any of this at home in your Mooney. The people at APS are some of the best most professional instructors I have run into, and that is something because my other instructors have been really good too.  If you want to learn this stuff, go spend some time with APS at KIWA.

Edited February 5, 2020 by jlunseth

[Ibra]

On 1/31/2020 at 4:22 PM, jlunseth said:

You are correct, in 4 & 5 I was talking about incipient and developed spins, not stalls.  Thank you for catching that.  I think my head is still spinning. I made the changes (I hope).  The only thing I didn't change was the statement about flying out of a stall, which can make the stall more difficult to resolve. Example, Air France 447. They may have eventually made it into a spin, I don't know, but it was pulling and attempting to power out of a stall that caused the problem (according to the reports). The right answer is PUSH.

Well, Spins as far as aerodynamics is concerned are nothing than stalls where one wing is stalled and the other is not (or both stalled but different high AoA)

Practically, it means you have to bring them to the same level of stall (using rudder yaw) and then un-stall both wings by pushing, you can't use ailerons to stop a spin in the same way as you can't stop a stall by pulling back on the stick (if wing drops use your feet), most certified types will stop a spin to normal stall with rudder action only other (uncertified types -with small rudder- need a prompt wide PUSH while you kick opposite rudder before it is too late) 

AF447, lot of the blamed on what happened bellow 2000ft can go to independent controls above that is blamed on complexity from automation/crew coordination and how all of that is robust pilot heat glitch, while not many of that applies to but let's imagine yourself at night/imc and feeling that you are losing it with no clue on attitude and contradictory instrument readings, which ones you trust? what if you can't regain control? and what you will do?

I have my personal answer which start by quickly cut power (works for stall/spin/dive ), trim slightly forward (Va = 1.3*VS0 = 80-90kts), do nothing with yoke and minimal use of (right?) rudder but I am too biased by gliders flying: 3/4 of my aerobatics flying were engine off including few unusual attitudes (once with dead battery and once ice clogged ASI in clouds)

 

PS: great videos and comment, also nice camera position at eyes level to see nose/horizon 

 

Edited February 6, 2020 by Ibra

[Volare]

I don't get any sound. Is there supposed to be any?

[jlunseth]

No sound, sorry.  I contacted APS to ask permission to post the. videos and they said go ahead, but please cut the audio so as not to give away their instruction strategy.  Its how they make their living, I respect that.  Too bad though, you would hear me say some choice words on a couple of occasions.

 

[jlunseth]

1 hour ago, Ibra said:

I have my personal answer which start by quickly cut power (works for stall/spin/dive ), trim slightly forward (Va = 1.3*VS0 = 80-90kts), do nothing with yoke and minimal use of (right?) rudder but I am too biased by gliders flying: 3/4 of my aerobatics flying were engine off including few unusual attitudes (once with dead battery and once ice clogged ASI in clouds)

 

PS: great videos and comment, also nice camera position at eyes level to see nose/horizon 

 

PUSH works in any attitude, provided you are not in a spin.  You will know if you are in a spin.  Then it is P.A.R.E., then rudder to neutral and elevator back to pull out of the dive.

I did a number of upset recoveries on instruments only.  As long as you are not in a spin, the AI will indicate correctly and the PUSH ROLL POWER STABILIZE strategy will work.  If you are in a spin your AI probably will not work, you will need to use P.A.R.E. (or whatever your POH says).

The folks at APS set up the camera, they do it for all their students.  I have five hours of being in some weird attitude, well, ok, three hours if you subtract the time to fly to the practice area and back.

Edited February 6, 2020 by jlunseth

[carusoam]

Way to go JL!

I think I supplied my own sound track for first couple of videos...

Everything is so nice and calm... until it isn’t!

We do get a nice view of the ground Through the top of the canopy   
 

+1 very woolly! 

Thanks again, and best regards,

-a-

[jlunseth]

18 minutes ago, carusoam said:

Way to go JL!

I think I supplied my own sound track for first couple of videos...

Everything is so nice and calm... until it isn’t!

We do get a nice view of the ground Through the top of the canopy   
 

+1 very woolly! 

Thanks again, and best regards,

-a-

You too.  Did you catch sight of any jackrabbits skittering through the brush trying to get out of the way?

I have one that is “wooliest,” I will put it up just for you tomorrow.

[Hank]

Great videos! Work just fine on my old Galaxy Tab A. I honestly (and most earnestly!) hope to never see that myself looking out the windshield of my Mooney.

Any idea how steep your recovery dives were? Judging from the little bit of horizon I think I saw flickering in and out of view, I'd guess more than 70°, but probably not as steep as the Mooney dive we all want to avoid.

[jlunseth]

No, I only had an AI, altitude and airspeed, and the AI was covered for the first day and a half. The instructor had all the good stuff, and it would depend on the maneuver anyway.  We did a few hammerheads, that is pure vertical, 0 Gs.

[Ibra]

7 hours ago, carusoam said:

Everything is so nice and calm... until it isn’t!

I was told Mooney drivers would never fly anywhere near stall or unusual attitudes, but now carefully watch autopilot: when he does not like it, he throws the yoke fully stalled or out of trim 

 

[jlunseth]

That is a very good point about the AP.  Know where the disconnect is and how to use it.  There are certain circumstances during an approach, just as an example, where my AP (KFC200) will pitch up strongly to get to the glide slope. You are low and slow. Leaving the AP connected and pushing on the yoke without disconnecting will cause the electric trim to run nose up to counteract your push.  

It would be very good if we never flew near stall or unusual attitudes, but anyone with any hours has done it at least once.  But over the years I have been taught two ways to get out of an incipient stall, (1) PUSH the nose over and worry about loss of altitude later, or (2) power up and fly out.  PUSH is the right answer.

[jlunseth]

Wooliest.  I count 11 or 12 turns and we lost over 3,000 feet (from 10,000 MSL) in less than a minute. There was a point to this.  The instructor put in several things to show that they had no positive effect on breaking the spin, they were, in order, power, elevator back, ailerons one way, then ailerons the other.  Power just brings the nose up and flattens the spin.  Back on the elevator, or ailerons the wrong way, accelerates the turn.  The spin was stopped quickly with P.A.R.E. then rudder elevator. We flew level for a minute or so afterwards so our internal gyros would stop spinning.

Edited February 6, 2020 by jlunseth

[carusoam]

JL,

What kind of speeds did you see when things stop flying and during the nose down recovery?

 

I imagine the desire to put the nose on the horizon must be controlled..?

Best regards,

-a-