Calling V1 early

[john_tullamarine]

Gents,

A bit of heated discussion here .. a chap goes off for the weekend and these things generally happen ... Perhaps we ought all to take ten deep breaths and start again.

For one, I see the basis of a very useful and rational discussion in this thread and the ideas being canvassed are important for folk to contemplate.

Just to throw a few more comments into the pot ..

(a) Sorry J_T, although the takeoff can be continued at a Flex/Derated thrust

Mutt,

Granted, but IF the hapless pilot pushes the levers up too far (or, in some cases, too quickly), the situation can be very different ... as we suspect was the situation in the accident vaguely alluded to ... crash, burn, die for crew and numerous folk behind them ... It is noted that my comments depend on the engine control systems.

(b) I don't believe it 'better training' would have changed it

Wileydog3,

Probably the discussion was getting a little bogged down in semantics along the way.

The general thrust of pilot training programs needs to be (and is) driven by pragmatic (and defensible) risk assessment, control, and management considerations. That is, the training has, as its aim, to condition pilots to respond to situations in a manner which, on the great majority of occasions, will have a high probability of a successful outcome. It is for this reason (why confuse the issue ?) that many training programs shy away from training exposure to low probability emergency scenarios .. while I don't agree with that, personally, it is a very logical and defensible argument.

Training then, and now, still emphasises the very sensible option of flying it in a manner which is consistent with the certification. I suggest that Alex and I have no criticism of the crew in the O'Hare accident .. they did the best they could in the circumstances of the day (and, indeed, no doubt as they had been trained)... it is a matter for extreme regret that things didn't quite work out for them as they would have hoped. As to what the outcome might have been had they hung onto the speed delta at the time is a moot point .. but it may have been better than that which ended up in the historical record ..

And we probably ought not discount the part played by Lady Luck (call it what you will) in all of this .. in the other example raised, the Sioux City outcome could conceivably have been far better had the crew not been caught out by the phugoid on late final .. it all comes back to the numbers game.

However, the point still remains that normal training programs do not offer an iron-clad guarantee of a happy outcome .. only that the odds are very heavily weighed in that direction. In fact it is not unreasonable to suggest that there are no hard guarantees in life ... only probabilities.

It is interesting to note that the test flying fraternity ... the training these folk get is a tad different to the airline line pilot's .. probably would side with the suggestion that when something goes bang generally it is preferable to leave other parameters as they are rather than potentially increase the problems associated with whatever it was went bang ... and I note that you side with this argument yourself in a later post. I suggest that Alex's comment about better training probably should be read in terms of better understanding ?

Should crews pitch up to the V2/V2+whatever target in the event of a perceived engine failure ? ... of course ... in general .. as that action will give a high probability of a desirable outcome .. but not a guarantee.

At the end of the day, one of the big problems we face in the training arena is how much information to give and how best to control outcomes .. there is no simple or easy answer.

(c) thread creep

Not at all an undesirable thing, in my view. A significant value of tech log is the potential for education in that we have some highly qualified, experienced and knowledgeable folk in this sandpit. Often a turn in discussion can entice some of these folk out from the sidelines to offer valuable comment.

(d) OK. Suit yourself

Are we all going to agree all of the time ? Of course not. Main thing is to keep the discussions alive and the civility high so that people are encouraged to participate and, hopefully, learn a bit here and there along the way.