Originally Posted by
dogcharlietree
I can appreciate what the airlines/manufacturers sprout. They have to to protect their butts.
Please remember that the main problem in a ditching is impact forces.
So doesn't the old equation E=mv2 come into play.
KE = 1/2 mv^2
Originally Posted by
dogcharlietree
If you double the speed at impact then you have four time the impact forces.
Double velocity, energy to be dissipated goes up by a factor of four. Without knowing a lot more, this only tells you the impact forces will be higher, not how much higher.
Originally Posted by
dogcharlietree
The airlines say approach at Vref (1.3 Vs), so as my mathematics is not that good, hypothetically if you came back to Vs (which you wouldn't) aren't you nearly halving the impact forces. (Donning flame jacket now).
1.3^2 = 1.69 which is close enough to double for the back of a napkin.