Originally Posted by
scifi
There is a formula which relates height loss to speed gained (due to gravity.). At these speeds for every 45ft lost you gain 10 knots, so if he dived 3x45 = 135 ft he would have gained 30 knots. The camera lens is most likely wide angle so the height loss is deceptive.
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I'm guessing that rule of thumb applies to a glide. The speed gained would also be dependent on the thrust being produced or more correctly the amount of excess thrust over the thrust needed to overcome drag.
As an aside, why do people persist in holding their phone in portrait instead of landscape when taking photos or videos that should be taken in landscape?