Jammed stab - You are either an amateur, a troll or just having a laugh. You are also changing the OPs initial question because contaminated runways did not come into their question. Furthermore, my understanding is that you have slippery runways, you will always be using full thrust, no matter what the length of the runway. The important thing is that it is safe enough and whilst the margins might not be as fat (we were not provided with obstacle data nor we we told how close we were to that perf. limit of the derate), they are adequate. So unless I'm given values to these margins, I'll take whichever runway fits in with my company's operation requirements. And are you also saying that if faced only being able to use the shorter runway, you wouldn't go even if the performance figures say you can?
We are paid to do what is possible. We are selected, trained and checked and then as crew trusted to operate aircraft with known performance charactics in a regulated environment adminstered by a similar teams of professionals. In addition to all of this, margins for equipment failure, measurement inaccuracies and poor handling etc. are added. So you can do us a now do us favour by telling us how much safer you would be by using the longer runway. Is it 20% safer or 32%? Lets have some numbers please. Or are you saying you are not prepared to fly to the legal limits?
I'll say it again. I the numbers say you are good to go, then you can go.
Derfred - My tongue was in my cheek. I was just trying to guess the direction of the thread.
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