PPRuNe Forums - View Single Post - Would you abort after V1?
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Old 21st May 2008, 00:18
  #197 (permalink)  
Diesel8
 
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"Un-commanded slat retraction - 1979, AA191

Obvious control jam, hard-over - 2001, LH A320 Cross-wired Sidestick

Double engine failure - 2001, S360 departure from EDI"

And in which ones of those were the a/c still on the ground past V1 with the ability to safely stop?

Cannot speculate on 191, although the uncommanded slat retraction was a we all know, due to the fact that the engine seperated from the a/c. Had it just been an engine failure, little doubt they would have survived. Had they stopped, for a "mere" engine failure past V1, it is not known, that the a/c would have stopped on the remaining rwy, it may well have plowed into houses, broken up and burst into flames. The report would have certainly faulted the crew for that, afte all, that would not be SOP nor the manufacturers recommendation.

In this article, you will notice, that the engine loss/slat retraction was deemed surviveable, after having re run the scenario in the sim, however, certainly we cannot blame the pilots on AA191, rest their souls, for the outcome. http://en.wikipedia.org/wiki/America...nes_Flight_191

LH was not a control jam, the controls moved freely, the CA sidestick was miswired, the F/O stick was working properly. They found out when the a/c was airborne, that is when the CA used roll input. He would not have been aware prior to V1, that is unless they had noticed the anomaly during the control check at taxi. Of course, in that case they never would have taken off. Certainly you are not advocating the LH pilots should have tried to land on the same rwy after having been airborne, with a stick malfunction to boot. That surely would have led to an overrun or worse, a crash. Interestingly enough, Airbus FBW do have a procedure for frozen or malfunctioning sidestick and no one was harmed in the incident.

The SD360 was at 1200 feet when they experienced trouble, a couple of minutes removed from V1, is that example even pertinent? Why not mention the SAS MD-80 out of Stockholm, they had dual engine failure a minute or two removed from V1. Maybe they Gimli glider should have aborted at V1 plus 20, then they never would have suffered dual engine failure in cruise.

None of your examples appear to offer much that is relevant, nor anything that supports the argument of stopping past V1. In two of the cases, the a/c was already airborne, with no indications of malfunctions prior to and in the case of AA, the crew had no indications of anything other than an engine failure. The AA crew at the time, made the right choice based upon what hey knew, since they couldn't possible have known the engine was torn off and that the slats would retract.

Statistic show, that the safest course of action, past V1, is to continue the takeoff. It has been proven time and time again. It is the recommendation of all FAR 25 manufacturers, all airlines, all training academies etc, etc.

Is it possible to come up with situations where it would not be the prudent course of action, yes it is. Dual engine failure on the ground, an aircraft that will not rotate, loss of an entire wing, etc. However, do any of those happen on such a recurrent basis, that it should be considered normal, besides, under such scenarios, is there even a choice?

Last edited by Diesel8; 21st May 2008 at 00:35.
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