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IX. TRAINING This section is intended to provide the reader with an understanding of the mechanics of an ice induced roll upset and provide the basics in terms of aircraft stall recognition and recovery. Conclusions: l Unusual attitude recovery procedures should include recognition and recovery from ice induced roll upsets or other aerodynamically degraded conditions. The FAA should require training in recognition and recovery from ice induced roll upsets or other aerodynamically degraded conditions. A. ICE INDUCED ROLL UPSET Questions of stall training are not new to accident investigation. Since 1986, research shows that multiple accidents and incidents have occurred as a result of a roll upset phenomenon which has, so far, been determined as NON aircraft specific. From this data, ALPA believes that the stall training mandated by the FAA does not adequately equip an airman to successfully recover from an event with an aerodynamically stalled or performance degraded wing. In Section 6 of the Plight Test Guide for Certification of Transport Category Airplanes (AC 25.7), the FAA acknowledges this fact when they state that “Since operational pilots may not be required, or trained, to fly to an angle of attack beyond that for stall warning, any exposure to the behavior of the airplane in an actual stall would be both unexpected and unfamiliar. The behavior of the airplane during the stall and recovery must be easily controllable using normally expected pilot reactions. ” B. STALL TRAINING AND FAA REOUIREMENTS A review of the Practical Test Standards for Private, Commercial and Airline Transport Certificates yields an interesting and significant dichotomy in stall training and testing philosophy. Both the Private and Commercial flight tests require full stall demonstrations. The applicant is required to L announce the first “aerodynamic indications of the oncoming stall, i.e., buffeting or decay of control effectiveness...” however the applicant must then continue the demonstration to the actual stall. Recovery must be accomplished “promptly after a stall occurs by simultaneously decreasing the pitch attitude, applying power, and leveling the wings to return to a straight-and-level flight attitude with a minimum loss of altitude appropriate for the airplane.” The applicant for the Airline Transport Pilot’s certificate is not required to demonstrate full stalls. In this test, the applicant is required to announce “the first indication of an impending stall (such as buffeting, stick shaker, decay of control effectiveness, and any other cues related to the specific airplane design characteristics) and initiates recovery...” The recovery requirements .make no mention of decreasing pitch attitude. Indeed, this section of the test requirement is titled “Approach to Stall”, and does not contemplate the airplane actually stalling. The FAA Safety Inspector’s 42 Handbook (8400.10) reads, “An applicant must recognize the first indication of the approaching stall and immediately initiate recovery with a minimal loss of altitude. An actual stall should not be allowed to develop.” There are two significant points to be made. 1. Stall Training and Testing First, it is important to recall the discussion put forth on stall certification in Section II B.l of this submission. The Flight Test Guide for Transport Category Airplanes (AC 25-7) specifically states I that the stall may be identified by a nose down pitch which “may be accompanied by a rolling motion that is not immediately controllable, provided that the rolling motion complies with FAR 25.203(b) or (c), as appropriate. “. FAR 23 tolerates only a 15 degree roll motion during recovery from wings level stalls in certification, while FAR 25 allows 20 degrees. However, in the case of turning stalls, both Parts tolerate up to 60 degrees of roll in the direction of the turn in the case of normal decelerations. Yet the Airline Transport Pilot applicant is not required to demonstrate proficiency or even familiarity with the fully stalled behavior of his type aircraft. Without such a requirement, he will not likely be afforded any training in these areas. He must only be trained to recognize “the first indication of an impending stall...and initiate recovery...” In the case of aircraft equipped with an artificial stall identification device, such as a stick pusher, there is no requirement that the ATP applicant demonstrate an approach to stall to the point of pusher activation. Thus, not only is the applicant unfamiliar with the aircraft’s actual stall characteristics, he is also perhaps unfamiliar with the aircraft’s behavior near and at the activation of the stall identification device. Certainly, in cases of airplanes prone to “deep stall” or other unpleasantly nasty stall characteristics’, training in such maneuvers in the airplane is inappropriate. However, it may be entirely appropriate in the simulator. Full stall training may be analogous to wind shear training as an ungraded maneuver. The irony of this is that in the case of small Part 23 airplanes, there is both a slightly more stringent stall recovery requirement in certification and almost no possibility of installing a stall identification device such as a stick pusher due to weight and costs. Thus the manufacturer must resort to changes in airfoil geometry, such as “washout” or the addition of stall strips, to produce an airplane with actual stall characteristics that are acceptably benign. Yet the private pilot applicant must demonstrate recovery from full stalls. On the other hand, Part 25 airplanes are allowed slightly less stringent stall recovery requirements, and they can tolerate the installation of artificial stall identification devices to provide protection against undesirable stall characteristics. But the ATP applicant must only demonstrate “approach to stall” maneuvers. 43 The stall/spin accident records of airline operations give good evidence that this system works well...until the pilot encounters a contaminated wing stall. 2. Impending Stall Identification In all of the FAA’s Practical Test Guides, there is one indication of an impending stall uniformly cited: “decay of control effectiveness”. In AC 61-67b, Stall and Spin Training, the FAA has pointed out that “One indication of a stall is a mushy feeling in the controls and less control effect”. It is presumed that all pilots are familiar with this characteristic. Apparently, autopilots are not aware of this characteristic. While aerodynamic warnings such as airframe buffeting are apparent with or without the autopilot engaged, a “decay in control effectiveness” is not apparent. This is the case for both pitch and roll controls. As was the case in this accident, the autopilot tolerates and attempts to compensate for the “decay in control effectiveness” until well past the point where a recovery from an impending stall should have been initiated. Thus, this single indication, uniformly cited in the Private, Commercial and Airline Transport Pilot Practical Test Guides as an acceptable means to make the required announcement to the examiner of an impending stall, is then denied to the pilot in the vast majority of actual line operations. In addition to the loss of the indication provided by “a decay in control effectiveness”, the pilot is also not afforded any artificial warning of an impending stall unless the manufacturer has opted to adjust the stall warning system threshold due to icing conditions. As stated in section II B. 1 of this document, ALPA firmly believes that systems designed to provide artificial stall warning and/or stall identification must automatically adjust their operating thresholds when icing conditions are detected. Aerodynamic buffeting may not be present in the case of an ice-contaminated stall, patticularly if the stall originates at the leading edge of the wing and/or at the tip instead of the root. Thus, the pilot of a transport category aircraft is examined for his license based on three typical Ic techniques for the identification of a stall: buffeting, stick shaker, and/or the decay of control effectiveness. Yet, in the case of a ice contaminated wing stall, the decay in control effectiveness is masked by the autoflight system, the buffeting may well not be present, and the stick shaker is looking for an angle of attack based on a dry wing. The airplane may provide the pilot with absolutely no indication that it is approaching a stall. 44 THIS PAGE INTENTIONALLY LEFT BLANK .

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