Well, I guess the legs would have to fold back up.
grasshopper didn't need to fold legs for re-fly. However, keeping pretty big volume of LOX and RP-1 where hot rocket is coming in is a pretty dangerous proposition. Ensured loss of barge in cases, similar to SES9...Also, safing/checkouts and refueling would probably take a day to perform. so, for typical ship lending, how much time you would actually save?same saving would be achieved if you make ship go 10 knots instead of current 5...
grasshopper didn't need to fold legs for re-fly.
Also, safing/checkouts and refueling would probably take a day to perform. so, for typical ship lending, how much time you would actually save?same saving would be achieved if you make ship go 10 knots instead of current 5...
What also might matter if launch cadence gets high is the availability of the drone ship itself. They need a lot more drone ships if each of them needs to travel back to port and back out after each recovery. (Then again having a few spare drone ships wouldn't hurt too much in case one sprouts a hole again or becomes otherwise unavailable for maintenance, overhaul or repair)
...Yup. And that's true for the other alternative, which is shipping the stage back by fast-boat after horizontalizing it...
Quote from: meekGee on 04/09/2016 09:46 pm...Yup. And that's true for the other alternative, which is shipping the stage back by fast-boat after horizontalizing it...Yes, that would be my solution to increasing the flight rate. Also I think it would be easier (and cheaper) to increase the stage inventory than get involved with complex processing ops off shore.
I really like the idea of fly-back, since it's a potentially same-day solution, compared to basically a two-week cycle for a barge that is 1000 km downrange.
Of course they might build a bigger one that has an inbuilt flame trench and launch clamps, cranes, etc...
Quote from: meekGee on 04/09/2016 10:19 pmI really like the idea of fly-back, since it's a potentially same-day solution, compared to basically a two-week cycle for a barge that is 1000 km downrange. Where is such a difference in estimated time is coming from? 1000km/5kt is basically 5 days.Remember, after fly-back, stage still need to be transported horizontally to the same hangar. So, difference in ground post fly/ship delivery is, literally, between tracking from port vs. tracking from landing zone; which, in the case of Port Canaveral, is negligible.From what I see, the difference is really only between time it take for ship to get to the port vs pre-re-flight checks and fuel load. And it actually not only fuel load, you need helium, nitrogen and whatever liquid used for fins. And I'm not sure if everything could be loaded from the stage bottom in current modification.
One potential issue with "gas and go" from the drone ship is that you don't have hold down clamps. You also have no payload, so the stage is relatively light - even when fuelled - that means even partial engine thrust will possibly give you >1.0 thrust2weight (depending on how many engines are used)The last (and for a quick refuel and go maybe only) possible point in time to see a major engine problem is when they ignite and ramp up thrust. During a regular launch, the computer aborts and the clamps don't release if there's something wrong.Sitting "loose" on its legs, the rocket has no such option. It also can't ramp up thrust too "slowly" (as to stay below 1:1 thrust2lift for the self check), as that would put a helluva thermal load on the deck. You want to get clear asap once that million-pounds-of-thrust-plasma-torch is lit.At least with the current drone ship. Of course they might build a bigger one that has an inbuilt flame trench and launch clamps, cranes, etc... Maybe SpaceX could buy or lease a decommissioned aircraft carrier - or an oil rig - from someone Does the old sea-launch rig still exist?