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On Thu, 24 Aug 2000 11:48:18 -0600, Razor wrote: >Regarding the Habsheim incident: > >While it was called pilot error, one could argue that the pilot was led into a trap by the A320 designers. Wrong. See below. >He was an Airbus test pilot, not a commercial pilot. Wrong. See below. >He pushed the throttles forward while doing a low approach to go around. The computer was in land mode, and did not respond to the throttle input. Wrong. See below. >Because the throttles are not back driven by the autothrottle on the A320, the throttles stayed where he put them, but did NOTHING to the engine power setting. Since the throttles did not move to the position the computer was commanding (like they do on the Boeing models), the pilot took a while to realize that the engines were not spooling up. Once he realized the problem, he pushed the TOGA button to command the computer to do a go-around. By this time, it was too late. The engines could not spool up fast enough, and he sank into the trees at the end of the runway. Wrong. See below. >The A320 flight deck does not have the best man-machine interface in the aviation world IMHO. IYHO. Wrong about the rest. Probably wrong about this too. >Regardless, I do agree that there is no data yet on what caused the crash in Bahrain, and speculation at this point is worthless. Well. One correct comment. Not a total waste of bandwidth after all. I posted this to the group on 12/12/1999 ---------------------------------------------------------------------- This crash is covered in Macarthur Jobs book "Air Disaster Volume 3", chapter 1. Some of the findings of the investigation listed in the book are: "...Throughout the descent, the engines were throttled back to flight idle with the speed reducing." "At 100ft AGL, the descent rate was still about 600fpm." "The captain levelled off at a height of about 30ft, engines at flight idle, attitude increasing." "Full power was rapidly applied when the angle of attack was 15deg and the speed 122 knots." "The response of the engines was normal and in compliance with their certification." "The accident resulted from a combination of the following: - flyover height lower than surrounding obstacles; - slow speed, reducing to reach maximum angle of attack; - engines at flight idle; - late application of go around power." Descending at 600fpm at 100ft. Levelling off at 30ft, with the engines at flight idle. Would anything bigger than an Auster climb over the trees? These books are an excellent read. ------------------------------------------------------------------------- And in response to another poster..... ------------------------------------------------------------------------- Not so much forgot as never knew. In my last post I tried not to quote too much from Macarthur Jobs book, but below is a bit more. I suggested reading the book. There are 13 pages on this accident, including maps and partial CVR transcripts. From "Air Disaster Volume 3" by Macarthur Job "...Because of the extensive and diverse experience of the two pilots, the Flight Division [of Air France] did not consider making any reconnaissance of the Habsheim aerodrome in preparation for the display flight. "...Captain Asseline was away from Paris taking delivery of the aircraft on the Friday, and was engaged in A320 crew training on the Saturday, while Captain Mazieres was off duty until Sunday. The two pilots thus obtained details of the operation only when they were handed the company file on the airshow request after reporting for duty at Charles de Gaulle Airport on the morning of the flight. Even then they were given no verbal briefing on the flyover, or on the details of the aerodrome at which it was being held. "...As set out in the crew instructions............make a low pass at low speed over Habsheims runway 02..... "...Neither pilot was familiar with Habsheim aerodrome or even its precise position, except what they had gleaned from their charts. "...at a height of only 450ft, the captain saw from the alignment of the airshow crowd that the axis of the flying display was not along Runway 02 as he had expected, but along a grass airstrip aligned northeast [34]. As the aircraft neared the airfield therefore, he gently banked to the right to re-align its ground track accordingly. "...At this stage the crew deactivated the Alpha Floor function, to prevent the computerised control system from automatically applying power as the angle of attack increased. "...A forest of young oak and birch trees... begins only 60m from the northwest end of Habsheims grass strip 34R. "The airshows invitation to conduct the low level flyovers at Habsheim aerodrome in the A320 had been studied by the relevant departments within Air France... These studies in the main consisted of checking obstacle clearances in the case of an engine failure, and were carried out with reference to Habsheims Runway 02/20, over which it was understood that the flyover would be made. "Although French air safety regulations officially required aircraft making such flyovers to maintain a minimum height of 170ft AGL in VFR conditions, it had long been the practice within Air France to conduct tourist and demonstration flights at airshows down to minimum altitudes of 100ft. "...In this case it is evident that the aircrafts descent towards Habsheim aerodrome and its positioning for the flyover was conducted with haste and without time to properly stabilise the descent, or to position the aircraft at the correct height, airspeed and power setting. It was also evident that task-sharing by the crew during this time was not as planned. "The aircrafts takeoff and climb to 2000 feet on QNH lasted two minutes during which both pilots were occupied with management of the flight. Only at this stage were they able to begin locating and identifying Habsheim aerodrome, which was unfamiliar to them both. As a result, the descent towards the aerodrome only began when the aircraft was less than six nautical miles from the field. This distance was insufficient to both lose height and decelerate in time to stabilise the aircraft at the planned flyover speed and height before reaching the airfield. [The total flight time was 4 minutes and 34 seconds] ------- Phil _--_|\ philmil@bigpond.com / \ New South Wales \_.--._* Australia |
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