cortilla, thanks for engaging. Yes I realise those things but will admit to being terribly rusty on the finer points
. I have looked at some PPRuNe archive where balanced field length/flex/de-rated comparisons are discussed, and even downloaded some 737 Perfomance charts. The reason I have not engaged much with the Performance arguments here (my mistake - laying myself wide open I guess) is because I think what I experienced was simply not normal for the operation. The performance numbers become a bit academic if airline ops have already indicated that full length take-offs are to be the norm at a particular airfield. Might that be possible or are commanders given full discretion without even occasional line recommendation on such things?
Remember that thus IS an airfield/airline combo where, once armed with the weather, the aircraft commander can usually choose (negotiate? but I really mean choose) a straight in approach even when earlier traffic may have been using the reciprocal only minutes before, and where he will 'choose' a straight-out departure on the reciprocal as often as he sees fit.
I sincerely hope it was possible on the day to rationalise our take-off using the numbers, but I do of course have a nasty feeling (which basically others have taken exception to) that SOPs or not, our 30 minutes late status may have (re-?) influenced our entry point at a late stage.
As I have laboured previously, we have never before in my memory taken off from that point, but I could be wrong
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