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A comment on SpaceX Grasshopper Flies High. Parent comment

Re:SpaceX Grasshopper Flies High by Florin_Andrei on Tuesday April 23, 2013 @05:50PM (#5598223)
> I imagine there's a lot less fuel required to land than is required to take off.

Right.

At take off, the delta vee is the escape velocity PLUS all the losses due to friction, which are tremendous.

At landing, the delta vee is only equal to terminal velocity. EDIT: Okay, plus some flying time on top of the landing point.

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Re:SpaceX Grasshopper Flies High by Someone on Wednesday April 24, 2013 @04:28AM (#5600434)
Another way to state this: at launch, air resistance is your enemy. When landing, it's your friend.
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