d105

Exactly what is that well known problem with "Flemish" speaking pilots? Flemish isn't a language by the way.

Admiral346

100%:
We use a similar tool on our laptop, and going out of my homebase with 4000m RWYs there`s always a lot of margin shown, even in winter.

But this does not mean I can safely abort above V1. At 140kts your aircraft runs some 75m per second. If it is not an A343 it will gain around 5 to 10 kts per second. So the next second it might be running 85 meters. So with an average time of becoming aware of a problem, assesing it, and taking action of some 5 seconds how far have you travelled down the RWY? How much is left? Consider that you are now at much higher energy than the calculated V1 abort.
Don't tell me you can calculate that, not even give a good guess, especially not while in the cockpit and not at a desk with a calculator and all the time you need.

I am sorry, but V1 tells me that if an abort is executed at precisely that speed and I have good brakes and tires I will get the machine stopped on the pavement.

The closer I get to V1 the less likely I will abort for some tire problem as my braking might not be what went into calculation. I am already guessing here as the factors involved are not known.



I recommend reading this report:

http://www.nlr-atsi.nl/eCache/ATS/15/694.pdf
Title "REJECTING A TAKEOFF AFTER V1…WHY DOES IT (STILL)
HAPPEN?"

It really changed my view on takeoff aborts, and on how little margin I am willing to accept, and when do I call "GO".

Nic

The Ancient Geek

Interesting.
Firstly the report only considers 'accidents' and 'serious incidents' which means that it does not include cases where the aircraft stopped safely on the runway with no damage or injuries. It is probably safe to assume that this implies that the decision to reject was incorrect but safe in such cases.

In the cases considered between 1994 and 2008 31.9% of the aborts were justified, 44.4% not, and 23.6% unknown. This does not seem unreasonable given natural human survival instinct and the need for a very rapid decision.

The critical problem here is the available decision time. Slow decisions are very dangerous due to rising speed and rapidly reducing space. Given that almost a third of the aborts were justified we must assume that a high proportion of these would have been fatal or highly dangerous if not aborted.

The important question that the report does not address is simple :-
We know that any delay in deciding to abort is dangerous.
Is it safer to make a snap decision to abort or to go, given the strong possibility that in almost a third of cases the aircraft may be unflyable.

How many fatalities have resulted from avoidable 'go' decisions compared to those from abort overruns and how many of the overrun fatalities are attributable to slow decisions and action.

Postman-LEJ

Oh Tosh, Locked Door!
without talent, you should not have wasted your money for ATPL training.

BTW, what talent do you need if you want to prevent loss of crew communication, misinterpretation and misjudgement of priorities combined with a "bare-ar+ed" breach of safe practices and law



It was either that or a simple brainfart.

It is also not the employers fault if trained standards are not executed properly by individuals. It's your personal responsibility to do so! Captain, FO, FA or Mech....no matter.

Removing the mistake maker may be cheaper, but not fairer. With good training this sort of incident need not happen so in this case I would hope a few sim details were the solution, not termination.

Sorry brother, but when's the last time you have experienced genuine fairness in aviation for the last time? You try to obey all the rules and not step on anyones toes. I was grateful for the time when the overall resposibility was not mine. The sim training he received seems sufficient for most others. The captain had the wits not to fight this wrong decision with the remaining runway being long enough. He was not trained for naughty things like that, either. And he "only" had 1000 h or so more experience.

In all "fairness" I can at least understand the removal.

cavortingcheetah

Not a very experienced crew then but not that inexperienced on the B737.

The captain, at the time of the event, had 3628 hours total flying experience with 2061 flying hours on type (B737).
The first officer, at the time of the event, had 2300 hours total flying experience and 1170 hours on type (B737).
The nine recommendations that might have been mentioned before can be found in here.

http://www.onderzoeksraad.nl/docs/ra...EI-DPX_ENG.pdf

bubbers44

Even though after V1 aborts are not recomended because of no data to support stopping distance it is still allowed if in the pilots opinion the aircraft may not be flyable. We don't know what would have happened if the Concorde had aborted after hitting debris on the runway. We saw what happened by continuing the takeoff. Who knows what those pilots knew about what was happening. Sometimes you know why things are going wrong, sometimes you don't.

It is hard to fault a pilot who in a split second has to decide which way to go. Blindly following the after V1 go vs I still have over a mile of runway left and do I really want to be in the air with this fire burning my right wing off decision.

Sometimes V1, if used, blindly as a go, no go speed can hurt you.

Once in a B727 I was over 10 knots below V1 when I lost a generator on #1 engine on a wet rainy morning out of Barbados with about 1,000 overcast at max TO wt. I told the engineer to take care of it hoping he would download a pack. He selected essential to #1 and of course we lost all essential power. I told the FO flying to keep going, he would fix it. Now we were at V1 and rotating at Vr. I'm sure our story would have been a lot more interesting if we had aborted at the time we lost #1 generator. I'm sure somewhere in that abort on a wet runway with no essential power we would have lost our antiskid.

As it was he switched essential back to #3, shut a pack off until we got our flaps up and put it back on, just as we could have dispatched with two generators.

GlueBall

It's unsettling and outright scary to learn of so many new-school pilots who find it acceptable to abort after V1 ....based on "runway remaining."