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The SpaceX recoverable first stage - how much does the landing legs and guidance gear add to the weight and what percentage of empty weight.?
And having a link to a source would be nice
2 個解答
- PaulaLv 75 年前
Well it is a considerable weight.
Not to mention the fuel that is carried to slow it down for a soft landing.
That is weight that had to be lifted at lift-off -- and it could have been used to get the rocket to a higher orbit.
And it is not just the legs, and the mechanism to deploy them and lock them in place.
The savings in re-using the first stage also have to off-set against the cost of refurbishing after each flight. Which includes having a barge out in the Atlantic Ocean.
The lessons learned from the Space Shuttle is that --
a) the cost of refurbishment can exceed the cost of building a brand new rocket.
b) raises the risk of a catastrophic failure.
- spot aLv 75 年前
Landing upright is a stupid idea. A good parachute system and a carefully planned launch will allow it to touch down on land by parachute, saving leg weight, guidance system and landing fuel which allows more weight to be launched