Rainboe
I am by no means an expert, but I believe you'll find that V1 calculations involve no additional increments. They are de facto performance calculations, under standard WAT conditions. Your statement, "I always understood a couple of seconds thinking time were already built into V1 calculations" refers, in fact, to the 'after V1' reaction buffers to bring the aeroplane to a stop.
It is my understanding that there was a one second, plus buffer, plus another second, plus buffer to get it stopped. This accounted for recognition AT V1, closing the thrust levers, apply max. braking and allow for spoilers up, plus an additional factor to stop. Under FAR 25 Amendment 42 an additional 2 seconds was added to the calculation of the Balanced Field calculation, which I suppose affects the initial V1 calculation.
Boeing has an excellent download called Takeoff Safety Traing Aid which explains everything in clear and uncertain terms.
Great discussion.
Empty Cruise
Thanks for the reference. I appreciate your trouble and truly must remember our friends who operate under the JARs. I stand better informed thanks to you.
cheers,
Willie
