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The best video ever on unusal attitude recoveries in airline aircraft

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The best video ever on unusal attitude recoveries in airline aircraft

Old 16th Sep 2019, 19:04
  #21 (permalink)  
 
Join Date: Feb 2000
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Sims and real life ... again!
WV's suggestion to roll the aircraft to stop a nose-high overpitch stemmed from the ACTUAL incident (which he referenced in the video) of a Tristar out of LAX or SFO (?) which entered uncontrollable nose-up pitch. The Capt used roll-off turns and differential thrust, 1&3 v 2. to get enough control to SAFELY get on the ground. As he pointed out, it isn't taught in the text books but it works!
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Old 17th Sep 2019, 03:26
  #22 (permalink)  
 
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Originally Posted by Cornish Jack View Post
Sims and real life ... again!
WV's suggestion to roll the aircraft to stop a nose-high overpitch stemmed from the ACTUAL incident (which he referenced in the video) of a Tristar out of LAX or SFO (?) which entered uncontrollable nose-up pitch. The Capt used roll-off turns and differential thrust, 1&3 v 2. to get enough control to SAFELY get on the ground. As he pointed out, it isn't taught in the text books but it works!
The incident you are referencing was Delta Air Lines Flight 1080: https://en.wikipedia.org/wiki/Delta_...es_Flight_1080:

"During the takeoff, the L-1011's left elevator became stuck in a fully upwards position, leading to the aircraft pitching up aggressively and causing the aircraft to lose speed and nearly stall. The pitching force, unable to be overcome by fully pushing the control column down, was counteracted by reducing the thrust on the L-1011's wing engines but not the tail engine. The differential thrust pitched down the nose of the airliner and allowed the pilots to land the aircraft."

As you see from the report, the aircraft was recovered mainly using differential thrust and not by rolling the aircraft to reduce the pitch attitude. I think WV overemphasized the use of rolling the aircraft to control the pitch up...you can read the pilot's summary here and roll is not mentioned: https://www.tristar500.net/library/flight1080.pdf
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Old 17th Sep 2019, 13:59
  #23 (permalink)  
 
Join Date: Jun 2019
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A very good read and another reminder that on occasion there will be malfunctions that are not covered in the published procedures, and that a healthy understanding of aircraft systems and aerodynamics can be critical to a safe recovery.
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Old 17th Sep 2019, 14:48
  #24 (permalink)  

Only half a speed-brake
 
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Originally Posted by Airmann View Post
Now in the Airbus there is no specific Microbursts technique, just Windshear which orders to follow the FDs. Wonder what Airbus would think of such a procedure, and what effect would Alpha protection on being able to carry it out?
The FD SRS mode commands in between 120 fpm and 22.5 N.U. A little cheating trick is that as you exit the worst, and can lower the nose down a bit to regain some sensible speed, not to dip below 15 - flight directors go there only temporarily due to the human pilot not following them perfectly.

Without the FD, the target is 17.5 as per the book.
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Old 26th Nov 2019, 05:34
  #25 (permalink)  
 
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Originally Posted by Judd View Post
Some flying schools have jumped on the band-wagon by advertising for pilots to pay to undergo training on light aerobatic aircraft to experience the "G" forces that occur and which may cause disorientation. All this in visual conditions of course. Personally I doubt the value of this type of training since unusual attitude recovery training in jet transport aircraft has little in common with an inverted spin in a Pitts Special.
If you literally mean "inverted spin" then yeah, not much value in that for what one will encounter in an airliner. But in general? Then I disagree, as I think there is huge value in doing unusual attitudes in real life, starting with basic acro "on purpose" maneuvers leading up into surprise upset recoveries. From my years of teaching this stuff, one of my lasting impressions is that most people's logic and flying reactions are overwhelmed on their first exposure to extreme attitudes, and the correct reactions will not happen. Any notion of a memorized mental list of steps given in ground school "training," by itself, is about as worthless as expecting someone to takeoff and land an airplane from only a classroom description.

There is no substitute for putting someone in the actual airplane in the actual environment, working past the "awe" and the sensory overload, and learning how to do the maneuvers and procedures. And, in line with the building-block approach, basic aerobatic maneuvers should be introduced first so as to teach people how to think and act in the new environment with a lower-workload set of tasks. Once that is comfortable, only then can those skills be meaningfully taken to the task of maneuvering out of a surprise unusual attitude. It would be a ludicrous expectation that someone interpret their suddenly-established/revealed roll attitude, find the nearest horizon, resist the temptation to pull through the bottom, and roll toward that nearest horizon, without first being able to do a simple aileron roll that is known about ahead of time.

You also mention the need for an IMC approach to this, and I agree; but only in the sense that it's a further building block, and not that that's a replacement for what I said earlier. What the instrument show you is a much narrower picture (literally) than what you see outside, but once you have interpreted what they're telling you, your next course of action is the same as what you (should have) learned to do in visual conditions. Of course, an EFIS screen gives you something closer to an outside picture than an old gyro.

You might also object that the much lighter control forces and greater reactions rates of an acro trainer are not representative of an airliner, but the advantages far outweigh these disadvantages. (I've always thought the best unusual attitude trainer is a Cessna 150 Aerobat... It's got a yoke instead of a stick like commercial airplane, and it's sluggish on the controls. If it could only have about 2 or 3 times the engine so it could climb!)
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