Stall Training Issue Addressed by FAA, Aviation Industry

Aviation International News » December 2012
Firefighters extinguish flames at the crash site of Continental Connection Flight 3407 operated by Colgan Air, near Buffalo, N.Y., on Feb. 13, 2009. Forty-nine people were killed when the Bombardier Q400 crashed into a house and burned. (Photo: REUTERS/Gary Wiepert)
December 4, 2012, 2:45 AM

At a time when aviation has achieved an extraordinarily high level of safety, regulators and safety organizations are pushing for more improvements in pilot training to preempt future accidents and ensure that new pilots entering the ranks start off with the right approach. One of the key areas receiving extensive examination is stall training, both in the early stages of ab initio training and how it is taught later to pilots who are flying sophisticated high-performance jets.

While accidents such as Air France 447 and Colgan Air 3407 drew attention to this subject, there are many examples of stall-related accidents in which two well trained professional pilots failed to recover from low- and high-altitude stalls.

In the U.S., politicians reacted to the Colgan accident by mandating that all new-hire airline pilots have logged a minimum of 1,500 hours, as if that would magically help prevent stall-related accidents. The FAA, while forced to accommodate the politicians’ legislation by enacting new regulations, also made a major change to its advisory material to reflect changing attitudes about stall training.

That change is embodied in Advisory Circular 120-109, which was released in August this year. The changes are also reflected in the Ifalpa Pilot Training Standards, Guide for Best Practices, published by the International Federation of Airline Pilots Associations in September.

In the Ifalpa guide, the key factor related to stalls is figuring out how to incorporate the startle factor into training. It says, “Startle helps explain why a pilot can demonstrate proficiency in a maneuver during simulator training yet fail to do the maneuver correctly when a similar situation is encountered during flight.” As the guide notes, pilots brief the maneuver before training flights, but still may be surprised when the same maneuver is encountered during normal flight. “The response of a startled pilot might include confusion, wrong identification of the situation or possible over-aggressive flight control inputs that could further complicate the situation (such as a stall) or result in an unrecoverable aircraft state.”

Ifalpa’s recommendation is that more effective training and not just rote checklist procedure accomplishment is better preparation for the startle effect: “The crew must be trained to suppress the startle response, confirm the situation then apply measured and proportional corrective inputs during realistic training scenarios to help create an appropriate response to unexpected aircraft states encountered during flight.”

This version of AC 120-109 is just the first part of an FAA effort to address full aerodynamic stall training, according to the FAA, and once developed, that information will be added to 120-109. The agency says that the purpose of the AC, for now, is to “provide best practices and guidance for training, testing, and checking for pilots, within existing regulations, to ensure correct and consistent responses to unexpected stall warnings and stick pusher activations.”

The AC clearly and unequivocally summarizes what every pilot should know from the earliest training, knowledge that has been subsumed in procedures that have emphasized minimal loss of altitude rather than reducing angle of attack: “This AC emphasizes reducing the angle of attack (AOA) at the first indication of a stall as the primary means of approach-to-stall or stall recovery [AIN emphasis]. Additionally, this AC provides guidance for operators and training centers in the development of stall and stick-pusher event training.”

According to the FAA, the way some pilots were being trained–minimal altitude loss during a stall–is no longer correct. The AC explains, “recovery profiles that emphasize zero or minimal altitude loss and the immediate advancement of maximum thrust have been eliminated. Emphasis is now placed on recognition and avoidance of those conditions that may lead to a stall event. Recovery procedures now emphasize:

• the immediate reduction of the airplane’s angle of attack,

• management of thrust and

• returning the airplane to a safe flying condition.

The FAA is not only emphasizing this tried-and-true yet neglected method by disseminating it widely but is also requiring that training organizations adopt this technique immediately. “The primary goal of testing/checking should be to evaluate a pilot’s immediate recognition and response to a stall warning and [his] timely, correct accomplishment of the stall recovery procedure,” says the FAA. The evaluation criteria should be changed, too. According to the FAA, “Evaluation of the recovery from an approach-to-stall should no longer be based on altitude loss. Pilots should be evaluated on their timely response and effective use of available energy (that is, altitude and speed) during stall recovery.”

The AC goes into much more detail on how training providers should update their stall training procedures, but two emphasized items are worth examining further. In one, the FAA discusses “abrupt pitch up and trim change commonly associated when the autopilot unexpectedly disconnects during a stall event. This dramatic pitch and trim change typically represents an unexpected physical challenge to the pilot when trying to reduce AOA. In some airplanes, this may be exacerbated by an additional pitch up when the pilot increases thrust during stall recovery.” This is the conspiracy of factors for not only the Colgan accident but also the February 2005 Circuit City Cessna Citation 560 crash, in which pilots failed to add power after leveling off during an approach. (The NTSB seemed more concerned with icing in the Citation accident, but the level-off without power and the autopilot disconnect during the stall were factors in both accidents.)

The other interesting emphasized item is this one, and it is fundamental, critically important and should be underlined and printed in bold type: “Reducing AOA is the proper way to recover from a stall event. Pilots must accept that reducing the airplane’s AOA may often result in altitude loss. The amount of altitude loss will be affected by the airplane’s operational environment (entry altitude, airplane weight, density altitude, bank angle, airplane configuration and so on). At high altitudes, stall recovery may require thousands of feet.”

The AC contains a lot of excellent advice, including training with stick pushers, startle factors, stall prevention and so on. But the essence, as emphasized above, is clearly and unambiguously stated, an example of FAA material that is on target, important and clearly aligned with the FAA’s goal of improving safety.

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Just an FAA guy
on December 4, 2012 - 10:50am

Interesting. Why don't you ask the FAA where's a new and seperate PTS for exclusive use at Part 142 training centers? Kind a like AQP?

Why are we still having air carrier folks doing no flap landings without the use of vertical guidance? PTS speaks to ADM and CRM. Why would anyone fly with secondary flight control failure to a runway without a glideslope, PAPI/VASI, or FMC built descent path? "You'd never do this in the real world, but for this check, I gotta see it". Should be a failure for not using it. Oh yeah, train the way you fly, and fly the way you train!

But its always been that way...

No Avatar
Just an FAA guy
on December 4, 2012 - 10:53am

<<<<<<<<<<<<<<<<<

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starviego
on December 4, 2012 - 12:36pm

Colgan3407 didn't stall, it suffered a malfunction in the prop pitch control, which caused the prop to 'disc,' among other problems.

Every witness on the ground said there were problems witn the engine, and a bunch of them said the plane was on fire as it came down.

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Matt
on December 5, 2012 - 5:02pm

While the NTSB final report notes that pilots increase the propeller RPM to slow the airplane down, there was no mention in the accident report about prop "disc" nor any witness statements about the airplane being on fire before impact. The evidence in the report seems pretty clear that the airplane stalled and that adding power would have prevented the stall.

http://www.ntsb.gov/doclib/reports/2010/AAR1001.pdf

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madt12
on December 5, 2012 - 6:13am

hello have you heard about the crash of the c295 EADS casa at lozer in france on the 9th november 2012 . it was an algerian military cargo . they were talking about stall after an investigation , i'am asking if you have some comments about it

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Matt
on December 5, 2012 - 4:47pm

Very little information is available about this accident, and I haven't seen anything about a possible stall situation.

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Natalie F
on December 6, 2012 - 9:16pm

I recently got into the "simulator training world" and was very happy when this AC came out. Finally, the basics we all learned in a c172 of puttin the nose down is finally ok for the big guys too. I was so surprised by the "only add power, and power out of a stall without losing altitude" attitude. Well, that might work with very well powered airplanes, assuming no problems (what if you had any kind of engine problem?). But try that AT altitude, say 30,000' or near the planes service ceiling. Good luck. Most modern jets are turbofan engines and simply don't produce enough power at high altitudes to "power out" of it. Even in small jets, stalling at those altitudes will require close to 1000' to recover properly, large jets, thousands. So reducing the AOA is most important. The AC really ought to require high altitude stall training as well, as I can tell you, the sim (or plane) is a whole different animal at 35,000' doing an approach to stall then it is at 7,000'. Students should see and train both. Secondary stall is very common when people use a 7000' recovery at 30,000'.

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Dave S.
on December 10, 2012 - 10:09am

This is a great article adout changes in pilot training. The funny thing is, I have been teaching this way for years as an instructor. This was always my argument and point. I wonder how many airline pilots are out there that don't have significant time as a flight instructor properly teaching stalls or upset rocovery training prior to joining the airlines. You will see a reference to "startle affect" as a flight instructor, you will get your daily dose of it. Obviously high performance jets are quite different than the prop planes used in flight instruction, but the fundementals are the same and proper stall recovery needs to be emphesised from the very beginning...angle of attack, not power, is the saving factor and is far more important. Integrating stalls into other maneuvers will teach a pilot to "recognize and recover" at any time and phase of flight. It will help a pilot to always be aware and ready for them. Rather than in training say "ok, were going to do stalls now". This is a great A.C.

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