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by lloyddobbler 4994 days ago
Now that's a freakin' cool article!

Freefall is generally defined in terms of vertical speed.

If you exit a DeHavilland Twin Otter that's doing 90 knots forward speed, yes, you get "forward throw" from the plane...but you still have to accelerate vertically before reaching terminal velocity. As a skydiver flying on your belly in an arched position, you usually fall at ~5 seconds per 1000 feet...excepting the first 1000 feet, which takes ~10 seconds to fall as you move from 0 vertical speed to 120mph.

(It's that age-old physics problem of whether the forward speed of a projectile has an effect on its downward velocity.)