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rogerrapoport
21st Apr 2016, 05:43
When Gary Helmer was writing his dissertation on Deceit and Misrepresentation of the Qualifications of United States Army Flight and Combat Mission Simulator Instructors he was determined to find out if there was a correlation between simulator training and actual aircraft accidents.

"I was unable to make a direct connection between the hiring of unqualified applicants who have apparently aggrandized their previous experience and education and the substandard training of aircrew members."

Dr. Helmer, now chief of the National Transportation Safety's Board's safety division, was not the only person asking this question.

Shem Malmquist, a veteran accident investigator and international MD-11 Captain has pointed out, "the simulator can't replace actual flight. We can use simulators to validate ideas on new training. But a simulator can't replicate every in-flight situation.

"Without correct parameters there is no way to accurately program a simulator. A classic example was incorrect simulator training that misled the pilots of an American Airlines Airbus 300, which crashed shortly after takeoff from New York's JFK in November 2001. The accident investigation revealed that a procedure created in an airline simulator recommended a new approach to handling an unexpected roll. The standard technique, using the aircraft's ailerons, was replaced with rudder deflection. Here, best intentions worked great in theory and failed dramatically in the air.

"Pilots are only as good as the instruction they receive. If they are simply handed a training DVD where they grade themselves on a multiple-choice test, or rushed through a short class that skips over critical details, they may not have the critical skills needed for a once-in-a-lifetime challenge. Likewise, simulators only work when manufacturers have the fundamental data required to make these machines effective for training. Unfortunately they are still limited in their ability to replicate the motion of actual flight. An inadequately trained pilot or an incorrectly programmed simulator can lead to unexpected consequences."

Over the past seven years three high altitude airliner stalls over the South Atlantic (Air France, 2009), the Java Sea (Air Asia, 2014) and in Mali (Air Algerie, 2014) have led to crashes taking the lives of 506 people.

Approach to stall and stall recovery training for these aircraft at cruise altitude was based on designing test standards rather than actual real world flight procedures. In addition there was an assumption that an actual stall at cruise altitude in a transport airplane was extremely unlikely. Government regulators accepted theoretical engineering data in lieu of in-flight cruise high altitude stall data.

In all three cases high altitude convective storms disrupted normal flight and the Airbus and MD-80 aircraft entered aerodynamic stalls. Although all three aircraft were flown by highly experienced pilots, including several with aerobatic training, none of these pilots had been trained how to recognize high altitude stalls. None of them had received correct training on how to recover from aerodynamic stalls at cruise altitude. They were also unfamiliar with the special icing conditions creating problems like unreliable airspeed.

A review of accident data shows that only a few well-trained test pilots had the training necessary to recover from these stalls. Following several accidents and after considerable study, the FAA saw the need for more robust stall training. The agency began collecting the data necessary in flight on Boeing 737 and Airbus 330 aircraft. These in flight 2014 cruise altitude stall tests and related data supplied independently demonstrated that industry wide simulator training for flight at stall and beyond stall angle of attack and stall recovery at high altitude was modeled incorrectly.

"Although my PhD thesis was more concerned with the quality of teaching there was a bigger unrecognized problem: the doctrine was wrong," says Dr. Helmer who also teaches at Embry-Riddle. "Combine bad information with bad instruction and you have an even bigger problem."

The FAA, the European Air Safety Agency as well as regulatory agencies in other countries are correcting the problem by requiring that all air carriers reprogram their simulators to make sure pilots can be correctly trained on approach to stall and stall recovery.

The FAA announced the new flight simulator regulation March 30, effective May 31. The simulator training upgrades must be completed by 2019. It is anticipated that carriers worldwide will eventually implement similar programs. This is already happening in Canada, Australia and the Middle East. Some carriers such as Alaska and Southwest are already making these simulator modifications well in advance of the 2019 deadline.

Complete details on the FAA's new 14 CFR FAR 60 final ruling, implemented at an estimated cost of $80.8 million can be viewed at https://www.gpo.gov/fdsys/pkg/FR-2016-03-30/pdf/2016-05860.pdf. American carriers must comply no later than March 2019.

ZFT
21st Apr 2016, 21:03
I would suggest the estimated costs are somewhat understated. Certainly the initial indications for the brand A stall buffet aero data updates appear to be around USD 0.25M per FSTD and that is without TDM implementation and integration costs.

Spooky 2
24th Apr 2016, 13:37
This is the number one highest priority item at Boeing sim engineering at this hour. Simulator data modules are being readied and there is no reason to believe they will not make the deadline. As to whether the actual simulators will ready is another issue and somewhat out of Boeing's control. To be continued.

Zaphod Beblebrox
28th Apr 2016, 01:08
I did our Airlines high altitude stall routine on both the B737-400, and the 320 series. . As a former light aircraft pilot I would say that one of the most significant issues, at least to me, is pilot stall perception. Civilian pilots who did their primary training in general aviation aircraft, Piper or Cessna or similar, are used to a definite stall break that signifies the full stall. It is easily observable and definite. I found this to be even more pronounced with aerobatic aircraft.

The B-737 simulator would stay in a stalled state with almost no break with an aft C.G. It required a forceful push and re-trim to get the nose down below the horizon and recover from the stall. The stick shaker and stall warning were going the whole time. It is easy to lose 3000 feet or more starting from 37,000. There is very little excess thrust available.

This situation is not recognizable as a stall with the prior training civilian pilots have had. Yes the stall warning devices are active and working but unless the pilot forcefully puts the nose down and lowers the angle of attack the stalled condition continues. Most light aircraft don't behave this way, not the trainers at least.

This is simply my own perception but I have a lot of time in the B73 and A320 and they both have a very wide cg envelope. The auto-pilot will also mask the problem as it re-trims to maintain altitude. You end up with the trim on the aft stop and an airplane that doesn't break the way a light airplane does in a stall.

FAR part 25.201(3) (d) says the following about transport category stalls.

3) As soon as the airplane is stalled, recover by normal recovery techniques.

(d) The airplane is considered stalled when the behavior of the airplane gives the pilot a clear and distinctive indication of an acceptable nature that the airplane is stalled. Acceptable indications of a stall, occurring either individually or in combination, are—


(1) A nose-down pitch that cannot be readily arrested;


(2) Buffeting, of a magnitude and severity that is a strong and effective deterrent to further speed reduction; or


(3) The pitch control reaches the aft stop and no further increase in pitch attitude occurs when the control is held full aft for a short time before recovery is initiated.


[Doc. No. 5066, 29 FR 18291, Dec. 24, 1964, as amended by Amdt. 25-84, 60 FR 30750, June 9, 1995; Amdt. 25-108, 67 FR 70827, Nov. 26, 2002]


While a nose down pitch that cannot readily be arrested, is one indication; but it is not a requirement. Buffeting and pitch control at the aft stop with no further increase in pitch attitude are also acceptable indications.

This is not something most former light aircraft pilots experience and we do not teach full stalls in the sim until the new regulations. The current sims may not produce the desired modeling anyway.

Here endith my limited knowledge of the issue.

westhawk
28th Apr 2016, 05:45
Capturing actual full stall flight test data for every single type of transport category airplane seems like a rather formidable task! Isn't that what has to be done in order to achieve the necessary level of fidelity?

ZFT
28th Apr 2016, 09:13
I would suggest (most, if not all of) the data has already been captured during the normal flight testing process on suitable instrumented aircraft.

misd-agin
28th Apr 2016, 15:57
Zaphod Beblebrox - I did our Airlines high altitude stall routine on both the B737-400, and the 320 series. . As a former light aircraft pilot I would say that one of the most significant issues, at least to me, is pilot stall perception. Civilian pilots who did their primary training in general aviation aircraft, Piper or Cessna or similar, are used to a definite stall break that signifies the full stall. It is easily observable and definite. I found this to be even more pronounced with aerobatic aircraft.

The B-737 simulator would stay in a stalled state with almost no break with an aft C.G. It required a forceful push and re-trim to get the nose down below the horizon and recover from the stall. The stick shaker and stall warning were going the whole time. It is easy to lose 3000 feet or more starting from 37,000. There is very little excess thrust available.


****************************************


The industry experts have said, repeatedly, that current simulator modeling does not replicate the aircraft in the real world. So believing the simulator is anything like the real world is not a realistic observation. It might be close, it might be significantly different. We just don't know.

mustangsally
30th Apr 2016, 01:35
High altitude stalls, the simulator just does not work. Years ago, I enjoyed hand flying to flight level. one climb required a slight turn just prior to reaching cruise level. As I rolled to the new heading we felt a very slight burble. I had maybe 15 degrees of bank. took out a couple of degree and the burble vanished. After leveling off and getting the books out, our cruse level was about 350 and the burble was about 340. At our flight weight we had something just short of 1.25 load limit. Well as I made the correct to the new vector, I exceed the 1.25 and got the burgle.
Was the wing stalled? One wing was and the other was almost. Was I in danger, no. It should be noted that the fight director, course was indicating this direction change. No harm, lesson learned!

ZFT
30th Apr 2016, 04:14
One should be somewhat careful with generic and sweeping statements such as "High altitude stalls, the simulator just does not work" as some OEMs have supplied the required data. Certainly brands A & B haven't yet and their current datapacks are (probably) more than lacking.

The TDMs can only simulate what they are supplied with and no one within the TDM world would ever suggest that they attempt to make a simulator anything like the real world (because that is neither feasible nor remotely possible without sustained G cues), only that is matches the approved (and typically OEM) supplied data

Willie Everlearn
2nd May 2016, 00:30
Today's full flight simulators are in the high 90s percentile of actual aircraft replication and performance.

The simple truth of the matter is this. We don't need to enter a fully developed stall at either low altitude or high altitude. Except it is soon to be a regulation. A small margin beyond the 'g' break is more than sufficient. In some aircraft, fully developed stalls are unrecoverable. The CRJ for example. Most T-tails.

The FAA, courtesy of the PTS and hundreds of over zealous POIs and Check Airmen, created this stall, loss of control mess in total violation of numerous manufacturers AFM recommended stall recovery procedures, particularly with regard to loss of altitude. Specifically, when talking about 3407, flight crew PTS stall recovery standard, and Q400 AFM recovery procedure. The Captain reacted as he was trained and according to the test standard he was held to, plus or minus 100 feet. Didn't work. Did it? But let's blame him for the prang. Everyone else, run for cover.

Regulated UPRT is unnecessary. Many claim LOC control is the number one cause of general aviation accidents today. Not airline accidents, general aviation accidents. But the proof is elusive. It is becoming an increasing contributing factor in accidents, but nowhere does it appear as a single cause or even one of two causes.

We can't allow any single link in the chain to be the single most concentrated effort on a solution to improving accident probabilities. For each accident has its own distinct series of errors in the chain. Instead, we need to focus on THE single link, if one exists, that needs remedy. Meaning, the single link causing an accident varies from accident to accident.

I'm surprised professional pilots aren't voicing their collective objection over much of what is being imposed by regulators and "safety experts" these days.
Aren't we suppose to be able to vet much of this before its imposed on us or at least question the validity?

Willie :ok:

Spooky 2
7th May 2016, 19:22
MustangSally I have no idea what your background is, but Boeing at least has accurately demonstrated high altitude full stalls in the B737NG simulator (CAE), as part of there EET envelope training program that is currently under development. Other models are to follow.
BTW, altitude loss was approx. 6000'

ZFT
7th May 2016, 21:43
MustangSally I have no idea what your background is, but Boeing at least has accurately demonstrated high altitude full stalls in the B737NG simulator (CAE), as part of there EET envelope training program that is currently under development. Other models are to follow.
BTW, altitude loss was approx. 6000'

Is this data freely available or in house Boeing use only?

Spooky 2
8th May 2016, 18:37
Well at this point and time, I'm sure it's proprietary while the Flight Services group along with other in house organizations develop the Extended Envelope Training simulator data packages. After that they will sell these sim data packages to the various sim manufactures and airlines that are qualified to purchase them. Sim data packages can cost millions so while they may be "available" they are not likely to be handed out like business cards.


I have heard that most of the data is available for the existing Boeing fleets as it was captured during certification. Also have heard that the same cannot be said for the Airbus fleets?

ZFT
8th May 2016, 22:26
Of course they will be sold as FSTD datapacks are a license to print money for the OEMs. I meant is it available now as you seemed to indicate the NG is ready?

Airbus have also indicated they have the data and have already given timescales for narrow and widebody datapack update releases.

Spooky 2
9th May 2016, 09:21
I said the EET program for the 737NG is under development and is awaiting FAA approvals. I have no control over what things like this cost so you're beating a dead horse when you complain about the costs. If Boeing is going to sell new 737NG's for 25 million a piece then the have to make it up somewhere:)

ZFT
9th May 2016, 10:12
I said the EET program for the 737NG is under development and is awaiting FAA approvals. I have no control over what things like this cost so you're beating a dead horse when you complain about the costs. If Boeing is going to sell new 737NG's for 25 million a piece then the have to make it up somewhere:)

I suspect we both have a good idea what "things like this cost" but a refreshing honest response nevertheless.