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Is it SpaceX's intention at some point to forgo the launch tower and launch directly off of the landing legs grasshopper style? I realize it's not really neces

Is it SpaceX's intention at some point to forgo the launch tower and launch directly off of the landing legs grasshopper style? I realize it's not really necessary, but it might make it easier to get a rocket off of Mars instead of having to build a tower. Although, presumably if you can refine rocket fuel on Mars, maybe building a launch tower is no big deal. Anyways, kudos again to Musk and SpaceX.

aschampion 12y ago
The strongback does a lot more than legs ever would: resistance to winds when awaiting the launch window, fueling, data connections, etc. Not to mention you need some sort of tower to lift the rocket upright after payload integration and servicing -- unless you do vertical integration, which they will need to do to win USAF contracts. But then you need a crane, anyway.
- ceejayoz 12y ago
  And eventually, you'll need a way to get the people in it.
- amatix 12y ago
  Genuinely curious, why would USAF (or anyone) need vertical integration?
  - rst 12y ago
    These requirements seem to apply mostly to "national security" payloads (e.g., spysats), so the exact nature of the requirements is classified. It's easy to come up with a plausible guess about what the requirements might be (optics going out of alignment if you tip the spysat on its side?), but those who know don't say --- and those willing to venture a guess, like me, are showing they don't actually know.
hga 12y ago
I don't know about the need for a "tower", but the Falcon 9 launch sequence includes firing up all the engines and making sure they're running fine. Same too for the SSMEs as I recall. That's one of the great advantages of liquid fuel rockets, you can turn them off. Ditto the mighty Saturn V, they started "8.9 seconds" before launch, 300 milliseconds apart. So you need some serious hardware to hold it down till release, and to deal with all that exhaust.
- gsnedders 12y ago
  SSMEs ignited 6.67s before launch. From memory, a lot of aborted launches were due to some sensor reading an error with one of the SSMEs.
toomuchtodo 12y ago
I don't believe the landing legs are rated to support a fully fueled vehicle; when the vehicle returns to land, it'll be bone dry after its final burn to stop it above the ground.
jccooper 12y ago
Probably not. The tower is used for horizontal transport and erection to vertical, for loading power and propellant to all stages of the rocket up until a few minutes before ignition, and for protection against strong winds. And, perhaps, loading last minute cargo (like people). So you kind of have to have it in the current configuration. And since you have to use a prepared range and pad, it's not that much additional infrastructure. One could perhaps design such a rocket, with storable propellants (liquid oxygen boils off, which is why they keep supplying it for as long as possible) and ground-level power connections. And on Mars the wind isn't really a problem. But that's a different rocket.

aschampion 12y ago

The strongback does a lot more than legs ever would: resistance to winds when awaiting the launch window, fueling, data connections, etc. Not to mention you need some sort of tower to lift the rocket upright after payload integration and servicing -- unless you do vertical integration, which they will need to do to win USAF contracts. But then you need a crane, anyway.

ceejayoz 12y ago
And eventually, you'll need a way to get the people in it.
amatix 12y ago
Genuinely curious, why would USAF (or anyone) need vertical integration?
- rst 12y ago
  These requirements seem to apply mostly to "national security" payloads (e.g., spysats), so the exact nature of the requirements is classified. It's easy to come up with a plausible guess about what the requirements might be (optics going out of alignment if you tip the spysat on its side?), but those who know don't say --- and those willing to venture a guess, like me, are showing they don't actually know.

hga 12y ago

I don't know about the need for a "tower", but the Falcon 9 launch sequence includes firing up all the engines and making sure they're running fine. Same too for the SSMEs as I recall. That's one of the great advantages of liquid fuel rockets, you can turn them off. Ditto the mighty Saturn V, they started "8.9 seconds" before launch, 300 milliseconds apart. So you need some serious hardware to hold it down till release, and to deal with all that exhaust.

gsnedders 12y ago
SSMEs ignited 6.67s before launch. From memory, a lot of aborted launches were due to some sensor reading an error with one of the SSMEs.

toomuchtodo 12y ago

I don't believe the landing legs are rated to support a fully fueled vehicle; when the vehicle returns to land, it'll be bone dry after its final burn to stop it above the ground.

jccooper 12y ago

Probably not. The tower is used for horizontal transport and erection to vertical, for loading power and propellant to all stages of the rocket up until a few minutes before ignition, and for protection against strong winds. And, perhaps, loading last minute cargo (like people). So you kind of have to have it in the current configuration. And since you have to use a prepared range and pad, it's not that much additional infrastructure. One could perhaps design such a rocket, with storable propellants (liquid oxygen boils off, which is why they keep supplying it for as long as possible) and ground-level power connections. And on Mars the wind isn't really a problem. But that's a different rocket.