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-   -   The best video ever on unusal attitude recoveries in airline aircraft (https://www.pprune.org/tech-log/625485-best-video-ever-unusal-attitude-recoveries-airline-aircraft.html)

Judd 13th Sep 2019 15:26

The best video ever on unusal attitude recoveries in airline aircraft
 
I have just watched this absolutely first class video on unusual attitude recovery techniques for airline aircraft. The link was cut and pasted from a thread on the subject currently in Pprune Rumours and News Forum. Produced by American Airlines circa 1997, the presenter was Captain Warren Vandenburgh (sadly now deceased). The link being buried among the many posts on that forum subject, I thought it well worthwhile to mention its value in Tech Log.


While the video and its associated series called Children of the Magenta Line has been around for many years, it has been my experience that very few of todays generation of airline pilots have even heard of the video, let alone seen it. In this writer's view, the video should be part of the induction process of every airline pilot. In recent times, there has been a plethora of documentation issued by regulatory authorities requiring simulator training of pilots in unusual attitude recovery action. 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.

What is missing from much of the documentation on the subject is the vital importance of instrument flying skill in interpreting what the flight instruments are telling you; especially if in IMC. Already we know that automation addiction/dependence can lead to degradation of instrument flying skill where manual flying is concerned . There is no shortage of evidence from accident reports where Loss of Control occurred, that poor instrument flying ability was a contributory cause. Vandenburg makes the vital point that the first action by the pilot should an unusual attitude occur, is to disengage the autopilot and autothrottle and recover to level flight manually. This is precisely where manual instrument flying skills if in IMC or at night are so important. Not being familiar with fly-by-wire types such as the Airbus series, I leave that subject to others more qualified.

In April 1967, the first edition of Handling the Big Jets was published in UK. Its author, D.P Davies, was then Chief Test Pilot of the United Kingdom Airworthiness Authority. Reviews of the book included this from the International Federation of Airline Pilots Associations News bulletin:... "can truly be described as the 'best of its kind in the world' and not only for the fact that there is no other book on modern aircraft handling characteristics....we can recall no book which bears so directly on the pilot's problem.. .written by a test pilot for airline pilots, the book is likely to become a standard text book."

I believe those accolades could equally apply to the video presentation by Captain Vandenburgh on the subject of Unusual Attitude Recoveries. Titles for the subject vary but the latest is Upset Prevention and Recovery Training or UPRT. However, in his presentation, it is notable that Captain Vandenburgh concentrates solely on the recovery technique from unusual attitudes; or Upsets as it is sometimes called. He leaves the prevention of an unusual attitude in the first place, to a pilots professional competency. In other words that's another subject. His point is to teach airline pilots what to do step by step if for any reason an unusual attitude has already happened. That is the beauty of the video. His instructional technique is superb, with just the right touch of dry humour.

The presentation shows diagrams of extreme attitudes that have been known to occur - including inverted flight. A classic example of a picture is worth a thousand words. He gives examples of what he has seen of unusual attitudes in simulator training. At least one major airline I know restricts its simulator training to manoeuvres that meet only the text book definitions of an unusual attitude; including bank angles of 45 degrees, nose high of 25 degrees, nose low 10 degrees. There is no simulator training outside these definitions; purportedly because simulator fidelity is not guaranteed. In turn, this misses the whole point that loss of control accidents have occurred precisely after these so called limitations to simulator fidelity have been exceeded. Warren Vandenburgh makes effective use of a model aircraft to illustrate extreme nose high and low attitudes right up to inverted flight.
This video should be re-visited during scheduled simulator sessions. It's value is that immense.

Cornish Jack 13th Sep 2019 20:36

Judd - Absolutely correct in that assessment!
I first came across this series when I was Tech instructing at a UK major and the series were amalgamated with a volcanic ash avoidance video and used for recurrent training sessions. I must have sat through the that combination at least 30 - 40 times and STILL found snippets which were valid. One effect of multiple watchings left me somewhat leery of a commonly held theory that the videos lead to the F O's over controlling yaw input in the New York disaster. Warren's advice was much more measured than has been suggested in some comments. A further area of interest, which, I feel, has had insufficient follow up action was the point he made in the Delta Tristar crash in windshear. He argued strongly for the inclusion of AoA indicating instrumentation " ... it's there in the FDR for the accident investigators but not for the pilots dealing with the problem!" ...
If there is anything to be said against the presentation, it's that an up date would be invaluable - but where would you find another WV!!

Tomaski 13th Sep 2019 22:01


Originally Posted by Cornish Jack (Post 10569405)
One effect of multiple watchings left me somewhat leery of a commonly held theory that the videos lead to the F O's over controlling yaw input in the New York disaster. Warren's advice was much more measured than has been suggested in some comments.

The presentations were only one, though an important, piece of American's Advanced Aircraft Maneuvering Program (AAMP). The lectures were followed up by sim sessions in which unusual attitude and stall recoveries were practiced. Unfortunately, as we all know now, the simulators were not programmed to accurately replicate the aircraft performance in these corners of the envelope. Thus one could employ aggressive maneuvers, including rudder use, in the sim and come away with the impression that nothing bad would happen in the aircraft. That combined with some little known aspects of the A-300's rudder response contributed to the FO's control inputs that led to the failure of the vertical stabilizer.

Fly Aiprt 13th Sep 2019 22:03

Great video indeed !
Thanks for retrieving the link.
Noticed the mention of puny elevator, incapable of ensuring -1g, contrary to fighters and aerobatic airplanes.

Le Flaneur 14th Sep 2019 01:31

The Danger of Generalization
 
I contend that AAMP video and the resulting simulator training were a contributing factor in AA 587 - reference 28:00 into the video where he talks about using top rudder. The AAMP and AA 587 were brilliantly summarized by UAL: "Aerodynamic principles do not change, but airplane design changes creates different flight characteristics. Therefore, training and experience gained in one model or type of airplane may or may not be transferable to another. For example, the handling qualities of a fighter-type airplane cannot be assumed to be similar to those of a large commercial swept-wing aircraft." - UAL B747-400 Flight Crew Operations Manual


Saint Jack 14th Sep 2019 04:17

A friend of mine is a retired B747 captain and had a unique(?) way of recovering from unusual attitudes in the simulator. He would simply put the aircraft into a spin and, as he often said, "when it's spinning I know what to do." In his younger days he had aerobatic training and did aerobatics in small single-engine aircraft. He retired from a premium Asian airline where he always did well in his simulator checks.

Cornish Jack 14th Sep 2019 08:37

Saint Jack - your friend possibly influenced by the late, great, Ernest Gann, whose 'Fate is the Hunter' autobiography described early aviation mail pilots' method of dealing with being above cloud at destination (no instruments for a let-down) They apparently induced a FLAT spin (minimum descent rate) and held it until either breaking cloud or hitting terra firma! ... in the latter case, the low descent rate made survival chances more possible. As your friend pointed out they all knew how to recover from a spin!. :ok:

Judd 14th Sep 2019 14:14


Ernest Gann, whose 'Fate is the Hunter' autobiography described early aviation mail pilots' method of dealing with being above cloud at destination (no instruments for a let-down) They apparently induced a FLAT spin (minimum descent rate) and held it until either breaking cloud or hitting terra firma! ... in the latter case, the low descent rate made survival chances more possible. As your friend pointed out they all knew how to recover from a spin!.
Deliberately inducing a flat spin is one thing but inadvertently finding yourself in one is something else. Slight thread drift coming up.
The following is a slightly edited report from a flying instructor who ejected from a Macchi jet trainer. It will make your hair stand on end.
Quote:
I was flying a Macchi equipped 70 gallon tip tanks. The spin was unintentional and unexpected as the student was attempting a stall turn after an inverted entry from 10,000 feet and a pull through to the near vertical, when the aircraft quite smoothly entered a spin.
I started counting the turns and after three turns I took over control of the aircraft and went to put on full opposite rudder and full nose down elevator input. To my surprise, this is exactly what the "pilot flying" was doing. I did identify and confirm with the student that the aircraft was inverted after which I eased the stick full aft.

The rate of rotation increased significantly and I initiated the ejection sequence. I understand that the subsequent report following inverted spin trials by a test pilot, found that on occasions the aircraft would 'tumble" and he recommended that deliberate inverted spinning should be prohibited. The incident aircraft did not tumble. I estimate that we were only airborne for ten minutes

misd-agin 14th Sep 2019 15:44

Exactly how many times were modern airliners spun in testing? Pretending that the simulator is realistic after stall AOA is a fantasy exercise. It wasn't until recently that Boeing and Airbus agreed to a generic narrow body stall characteristics. As one test pilot commented 'wide body characteristics are (can be?) different.' How did a common w/b stall in the sim? Very docile, just like the plane flies when it's not stalled. What did it actually do in testing? Rolled greater than 90 degrees. Did the manufacturer fix that post stall roll issue? IDK. We need to get aware from believing that old simulators accurately depicted post stall AOA characteristics just like we need to not believe that the current generic n/b stall characteristics and exactly how our non-generic airplane will behave in real life. It might be slightly different but the generic model is much closer to reality vs the old fantasy simulator flight characteristics after stall AOA model.

ehwatezedoing 14th Sep 2019 17:13


Originally Posted by misd-agin (Post 10569926)
How did a common w/b stall in the sim? Very docile, just like the plane flies when it's not stalled.

Your bad exemple would be Air France 447.
Went down in a very docile stall apparently... So docile they couldn't figure it out.

Fly Aiprt 14th Sep 2019 17:27


Originally Posted by Cornish Jack (Post 10569674)
early aviation mail pilots' method of dealing with being above cloud at destination (no instruments for a let-down) They apparently induced a FLAT spin (minimum descent rate) and held it until either breaking cloud or hitting terra firma! ... in the latter case, the low descent rate made survival chances more possible. As your friend pointed out they all knew how to recover from a spin!. :ok:

That's what I have been taught (but never had to experience ;-) provided we were sure of the ceiling below (no GPS then, but VHF).
The idea was that the spinning aircraft is in a known and airframe-kind configuration, contrary to an attempted blind let-down with the risk of overstress in case of loss of control.
Normal spin, though...


misd-agin 14th Sep 2019 20:08


Originally Posted by ehwatezedoing (Post 10569956)
Your bad exemple would be Air France 447.
Went down in a very docile stall apparently... So docile they couldn't figure it out.

Actually they were banking between 20 degrees to the right and 40 degrees to the left, with limited control of their bank angle. The simulators are more docile than that leaving guys with a false impression of how docile/stable their jets actually are.


Cornish Jack 14th Sep 2019 20:32

Simulators are ... simulators!
There was a fairly lengthy thread here on Pprune some years ago following the response of (IIRC) a United Co-pilot who had to deal with a destructive engine failure shortly after Take-Off. He had considerable problems adapting to the noise and, particularly, the vibration and consequent difficulty in instrument scan. He made the point, quite forcefully, that nothing in the sim had provided adequate preparation for the 'real thing'!

Airmann 15th Sep 2019 13:23

So I watched that video and then moved on to watch the video on Microbursts. A few takeaways .

1. His procedure to get out of nose high would probably get me a fail in the sim. He talks about turning the aircraft to up to 70 degrees and to not just lower the nose. Why, because the passengers would be uncomfortable with the negative Gs! Does anyone here fly for an airline that adopts such a procedure other than the situation that elevator control is not available?

2. In the microburst video

​​​​

he advocates the procedure of setting max thrust and the nose to 15 degrees (presumably standard TO/GA initial attitude) and leaving it there, basically ignoring the FD and the speed. Says that one would be far more likely to survive through the changes in wind in such a situation. 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?

A37575 15th Sep 2019 16:05


1. His procedure to get out of nose high would probably get me a fail in the sim. He talks about turning the aircraft to up to 70 degrees and to not just lower the nose. Why, because the passengers would be uncomfortable with the negative Gs! Does anyone here fly for an airline that adopts such a procedure other than the situation that elevator control is not available?
His quip about passengers and negative 'G' was just that - a witty remark.
Warren Vandenburgh's advice to get the nose to drop if faced with an extreme nose high situation by initiating a bank angle up to 70 degrees (depending on how high the nose was to start with) to the nearest horizon, concurs with the current advice in the Boeing 737 series FCTM except Boeing limit the bank angle to 60 degrees.


Edited for brevity: Quote: "If normal pitch control inputs do not stop an increasing pitch rate, rolling the airplane to a bank angle that starts the nose down should work. Bank angles of about 45 degrees up to a maximum of 60 degrees could be needed. Unloading the wing by maintaining continuous nose-down elevator pressure keeps the wing angle of attack as low as possible, making the normal roll controls as effective as possible....the rolling maneuver changes the pitch rate into a turning maneuver, allowing the pitch to decrease...

Finally, if normal pitch control then roll control is ineffective, careful rudder input in the direction of the desired roll may be required to induce a rolling maneuver for recovery... only a small amount of rudder is needed...too much rudder applied too quickly or held too long may result in loss of lateral and directional control.

Because of the low energy condition, pilots should exercise caution when applying rudder. The reduced pitch attitude allows airspeed to increase, thereby improving elevator and aileron effectiveness. After the pitch attitude and airspeed return to a desired range the pilot can reduce angle of bank with normal lateral flight controls and return the air[plane to normal flight." Unquote.

Seems to me that Vandenburgh's and Boeing's recommendations re recovery technique from a nose high unusual attitude, are indeed in broad agreement.

If as you say, that his (Vandenburgh) procedure to get out of nose high would probably get you a fail in the sim, I would suggest that your instructor is in need for some dual instruction on unusual attitude recoveries himself, before being let loose on future students..

misd-agin 15th Sep 2019 16:19

A37575 - is your quote from the Boeing FCTM? Or is that from W.V.'s presentation? If it's from Boeing it's interesting that Boeing has included the use of rudder. That's exactly what W.V. said in his video. But, like Boeing, he cautioned about the amount of input and using it when other roll control wasn't effective.

172_driver 15th Sep 2019 16:29

From the 737 FCTM:

If normal pitch control​ inputs do not stop​ an​ increasing pitch​ rate, rolling​ the ​
airplane to​ a bank​ angle that​ starts the nose down should work. Bank​ angles of ​
about 45°, up​ to a maximum​ of 60°, could​ be needed. Unloading the wing by​ ​
maintaining​ continuous nose-down elevator​ pressure keeps the wing angle of ​
attack as low as possible, making the normal roll controls as effective as possible. ​
With airspeed as​ low as​ stick shaker onset, normal​ roll​ controls - up to​ full ​
deflection of ailerons and spoilers - may be used. The rolling maneuver changes ​
the pitch rate into a turning maneuver, allowing the pitch to decrease. Finally, if ​
normal​ pitch​ control then​ roll​ control is ineffective, careful​ rudder input in the ​
direction of the desired roll may be required to​ induce a rolling maneuver for ​
recovery.​
Only a small amount of rudder is needed. Too much rudder applied too quickly or ​
held too long may result in loss of lateral and directional control. Because of the ​
low​ energy​ condition, pilots should exercise caution​ when applying​ rudder.​
The reduced pitch attitude allows airspeed​ to increase, thereby​ improving elevator ​
and aileron control effectiveness. After the pitch attitude and airspeed return​ to​ a ​
desired range the pilot can reduce angle of bank with normal​ lateral flight​ controls ​
and return​ the airplane to normal flight.

Airmann 15th Sep 2019 18:42

Ok thanks for the clarification, and I’m glad I watched the video. I assumed his recommendation was for all nose up situations.

misd-agin 15th Sep 2019 19:03

Thanks. The difference between 60 and 70 degrees is for lawyers. The concept is the same. In single seat jets we'd go to 90 degrees (yes, I'm aware airliners are different). The concept is the same, the nose will drop allowing the aircraft to accelerate. Delta 1080 departing SAN back in 1977 could have used this technique while they were trying to figure out how to establish a stable pitch attitude if they needed to lower the nose faster than they were able to with thrust alone.

Cropduster 16th Sep 2019 15:57


Originally Posted by Airmann (Post 10570481)
So I watched that video and then moved on to watch the video on Microbursts. A few takeaways .

1. His procedure to get out of nose high would probably get me a fail in the sim. He talks about turning the aircraft to up to 70 degrees and to not just lower the nose. Why, because the passengers would be uncomfortable with the negative Gs! Does anyone here fly for an airline that adopts such a procedure other than the situation that elevator control is not available?

2. In the microburst video

​​​​
Microburst Video

he advocates the procedure of setting max thrust and the nose to 15 degrees (presumably standard TO/GA initial attitude) and leaving it there, basically ignoring the FD and the speed. Says that one would be far more likely to survive through the changes in wind in such a situation. 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?

Airmann...the difference is that the Airbus in normal law has the very sophisticated SRS system at work, backed up by Alpha Prot/Apha Floor. For Boeings and other aircraft with less sophisticated flight directors, this is good advice. It will stop you from chasing the flight directors.


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