PPRuNe Forums - View Single Post - Rejecting A Takeoff After V1…why Does It (still) Happen?
Old 7th Dec 2010, 23:20
  #69 (permalink)  
SNS3Guppy
 
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Put away the crash reports...more airliners FLY to the scene of the accident then roll to the incident on departure.
Precisely because we don't reject after V1.

Seems it's working, isn't it? Perhaps we, the professionals, know our jobs a little better than you. Could it be?

If they tell you that your brakes will work 100% of the time from a V1 RTO....I can guarantee that 5 knots faster is not some magic wall you have crossed where you go from 100% reliability to 100% failure. It doesn't work that way.
You really have no idea what you're talking about, do you?

There is nothing "magic" about being five knots faster than V1, but you do understand that V1 is not a fixed number, and has direct and critical application to a number of factors, most specifically the length of the runway in use, as well as the stopping distance available after reaching V1; you do understand this, right?

Often when we plan a takeoff, we have just enough runway to stop if we reject before V1. After V1, we do not have the runway to stop. This has nothing to do with magic. It has everything to do with the physical runway available, period, end of story.

V1 is a very, very important number, created, crafted, and calculated specifically for this takeoff, right here, right now, on this day, in this place, in this airplane, at this weight, at this temperature. It is not a magic number. It is a performance number that has very significant import with respect to our decision making process when we either reject the takeoff, or continue. Given the amount of data that goes into producing this number for this takeoff in this airplane under these conditions, what on earth makes you think you have the spice to come up with your own alternate reality on the fly? You don't; this is why we do our performance calculations before we take off. This is not mindless data; it's critical information.

So just for the record if you have the runway to stop, but are willing to fly a burning wreck through the air because you feel your brakes will fail, because your 5 kts over V1, I don't agree.
You're not a pilot, are you? If you are, you failed to grasp basic performance concepts. Unwrap your head from around the "brakes-will-fail" mentality and accept that it's far more than a braking issue.

SSG is back. Again. New name, same, stupid material.
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