Re:SpaceX Grasshopper Flies High
by Florin_Andrei on Tuesday April 23, 2013 @05:48PM
(#5598217)
> All that hassle to reduce the terminal velocity by a couple hundred miles an hour.
That's the TLDR. The delta-vee from the parachute is not worth the trouble.
Or put it another way, parachutes are generally less effective than using a system you already have for other purposes. A parachute probably beats a rocket engine if your only task is landing, but when you already have the rocket engine, you're better off using it for landing than building a completely separate landing system.
In short, same basic reason why we use wings and wheels to land airplanes rather than dropping them from a parachute when they reach their destination.
Parachutes (and associated equipment) are heavy, so you'll burn fuel lifting that extra weight.
Parachutes are complicated, and would be an extra system to develop, test, and validate.
Parachutes are annoying to repack/replace (increasing turnaround time).
Parachutes put odd stresses on large objects when they deploy (increasing the amount of inspection you would have to do after each flight).
All that hassle to reduce the terminal velocity by a couple hundred miles an hour. That's not that big a win for a pretty high cost.