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Old 1st Jul 2005, 07:29
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catch 22
 
Join Date: May 2000
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747 classic brakes

As posted earlier the brake setting of Min and Med are based on decelerations of 4 Ft/sec/sec and 6 ft/sec/sec. Due to form drag on landing and spoilers the airplane will usually decelerate at least 4ft/sec/sec until about 100 knots. Then, with Min brakes the brakes will start to retard the aircraft. With Med the brake will start applying almost immediately. If you recall that the energy absorbed is related to the SQUARE of the speed you can see that at 140 knots much more energy is produced than at 100 knots. I will wager that under ALL circumstances Min braking produces less heat than Med. In practice that is also my experience.
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