Actually I don't think you can say that 410 km/h is almost twice as fast as usual however...
410 km/h = 220 kt
At Max Landing Weight (56 tons) FLAP 40 Vref = 138 kt
Approach speed would be 143 kt. Assuming the temperature was 30C the TAS would be 148 kt.
220/148 = 1.486. (You could hardly say that was almost twice as fast as usual.)
However 1.486^2 = 2.21 (You CAN say it had OVER TWICE the kinetic energy that it should have had.
Put another way, it had the combined energy of two B737's. One approaching at the correct speed of 148 kt TAS (143 kt IAS), and the other approaching at 162 kt TAS (157 kt IAS).
Or put even another way, it had the same enery as three B737's. Two at the correct speed of 148 kt TAS and the third at 66 kt TAS.
(148 kt = 272 km/h)
(66 kt = 122 km/h)
Don't underestimate the power of velocity squared!
Last edited by Blip; 7th Apr 2007 at 00:48.