SpaceX long-term stage processing goal = 48 hour turnaround

[Jim]

We are not talking about the airframe or the rest of the vehicle.

I am.

http://forum.nasaspaceflight.com/index.php?topic=39195.msg1470263#msg1470263

[sublimemarsupial]

1. It was still the same tank structure as V1.0 which you claimed up thread had to be upgraded with V1.1 for reuse. Grasshopper flew 8 times using the same body as any of the other 5 V1.0 cores that flew.

2. some can some can't, but the point is that even if the restart 'kit' wasn't added to the 1st stage, the engines were demonstrating the capability in the 1C version and at McGregor they were tested for much longer to test for eventual reuse even though the first recovered engine was in fact two generations later (1D FT, after 1D)

3. Again you assert stuff and it is inaccurate, the 1st COTS flight did a restart of the 2nd stage and I assert this was for testing purposes to prove engine restart capability for both recovery AND for GSO which would only take place with V1.1

1.  Again, not unique to falcon. any launch vehicle could have flown on the landing legs frame.
2. Wrong all can because they are test fired before delivery.
3.  Look no further than your post for wrong assertions.   There was no restart on COTS 1 because the stage was spinning. All upper stages have restart.  It is a necessary capability.

Sounds like you were thinking of F9 flight 1, but even then they did attempt a restart. It failed because the stage was spinning and the prop inlets were uncovered but they did attempt it.

As I recall in 2013 and 2014 you were claiming v1.1 had nothing to do with reuse, and it was purely because 1.0 didn't have enough performance. Funny how stories change.

[nadreck]

1. It was still the same tank structure as V1.0 which you claimed up thread had to be upgraded with V1.1 for reuse. Grasshopper flew 8 times using the same body as any of the other 5 V1.0 cores that flew.

2. some can some can't, but the point is that even if the restart 'kit' wasn't added to the 1st stage, the engines were demonstrating the capability in the 1C version and at McGregor they were tested for much longer to test for eventual reuse even though the first recovered engine was in fact two generations later (1D FT, after 1D)

3. Again you assert stuff and it is inaccurate, the 1st COTS flight did a restart of the 2nd stage and I assert this was for testing purposes to prove engine restart capability for both recovery AND for GSO which would only take place with V1.1

1.  Again, not unique to falcon. any launch vehicle could have flown on the landing legs frame.
2. Wrong all can because they are test fired before delivery.
3.  Look no further than your post for wrong assertions.   There was no restart on COTS 1 because the stage was spinning. All upper stages have restart.  It is a necessary capability.

1. Upthread you asserted that the V1.0 body structure could not support recovery/reuse - the grasshopper did

2. Not all can run for 30 minutes or longer, and the testing that was being done at McGregor was meant to qualify the engine from early on (at least as early as the 1C if not the original Merlin) for repeated use.  I can't quickly find a reference to a liquid engine that can only be run once, but I remember reading of them somewhere here.

3. "all upper stages have restart" ROFL how about trying to restart a CASTOR or STAR!!! and here is one quick reference to the restart of the COTS1:  https://en.wikipedia.org/wiki/SpaceX_COTS_Demo_Flight_1#Second_stage

[Jim]

1. Upthread you asserted that the V1.0 body structure could not support recovery/reuse - the grasshopper did

2. Not all can run for 30 minutes or longer, and the testing that was being done at McGregor was meant to qualify the engine from early on (at least as early as the 1C if not the original Merlin) for repeated use.  I can't quickly find a reference to a liquid engine that can only be run once, but I remember reading of them somewhere here.

3. "all upper stages have restart" ROFL how about trying to restart a CASTOR or STAR!!! and here is one quick reference to the restart of the COTS1:  https://en.wikipedia.org/wiki/SpaceX_COTS_Demo_Flight_1#Second_stage

1.  it can't.  It is supported by a frame that takes the landing loads.

2.  Those with ablative thrust chambers but those are pressure fed and not really "engines"

3.  Not relative to this discussion. Those are SRM's and not upper stages  (second stages) and still require another stage or the spacecraft to finalized the orbit.  They also don't do GTO missions.   Antares is designed around the ISS delivery mission and would need a 3 stage for other missions.

[nadreck]

1. Upthread you asserted that the V1.0 body structure could not support recovery/reuse - the grasshopper did

2. Not all can run for 30 minutes or longer, and the testing that was being done at McGregor was meant to qualify the engine from early on (at least as early as the 1C if not the original Merlin) for repeated use.  I can't quickly find a reference to a liquid engine that can only be run once, but I remember reading of them somewhere here.

3. "all upper stages have restart" ROFL how about trying to restart a CASTOR or STAR!!! and here is one quick reference to the restart of the COTS1:  https://en.wikipedia.org/wiki/SpaceX_COTS_Demo_Flight_1#Second_stage

1.  it can't.  It is supported by a frame that takes the landing loads.

2.  Those with ablative thrust chambers but those are pressure fed and not really "engines"

3.  Not relative to this discussion. Those are SRM's and not upper stages  (second stages) and still require another stage or the spacecraft to finalized the orbit.  They also don't do GTO missions.   Antares is designed around the ISS delivery mission and would need a 3 stage for other missions.

1. the frame does not extend beyond the base and that frame was attached to a V1.0 body

2. sure just like the Castor and Star series upper stages I mentioned aren't really upper stages 'cause they don't fit what you said previously about upper stages

3. see number 2, see https://en.wikipedia.org/wiki/Star_48 it is an upper stage for geosynch missions,  note THAT THE COTS-1 upper stage did restart!!!

[Chris Bergin]

No, no, no - this is not a Jim Q&A thread. Jim, I'm sure you've made the point you're trying to make. Everyone else, move along and get back to making your own points, which are as valid on a discussion forum as any one elses.

Anyone not happy about that, consider going to the next Jim seminar, but book soon - tickets are going fast!

[llanitedave]

I would definitely like to see more discussion about the ground equipment needed for fast turnaround.

[rcoppola]

Indeed. I'm very intrigued by how you could automate leg, 2nd stage and fairing (payload) attachment all the way through to an automated pully-type system that then takes the complete rocket/TE up the ramp, link to hydraulic pistons, rotate vertical, lock, auto attach/lock fuel/electrical, initiate fueling, Handoffs, TE retraction and off it goes.

Off course there's much more involved and there'd have to be some personal touches but that would be an epic Rube-Goldberg-Machine...sort of..

Has anything like that entire sequence ever been automated before to such a degree in this industry? What can they take from the car industry and what Tesla and/or BMW is doing with automation?

[Jim]

Car industry is not really applicable.  Cars are build on the order of 48 per hour vs 1 per 48 hours.  Don't need that complexity.  The stages are brought in by trailer into the hangar.  Slings are attached and the stages are lifted off the trailer onto support stands.  it just "takes" a little push of the stands moving them closer to mate the stages.  Manlifts and access stands are used to get to the mating areas to make mechanical, electrical and fluid connections.  Testing commences.   Once complete, the whole vehicle is lifted by crane, the support stands are moved out of the way and the launcher is rolled in.  The vehicle is lower onto the launcher and again connections are made and tested.

[guckyfan]

The legs are the single largest pieces of equipment to be attached. An industrial robot can handle them. Maybe humans still make the connections. One step on preparing preflown stages could be handling them with the legs on. Getting the legs off for transport and remounting them got to be one of the more complex, manual labor processes in the flow.

Otherwise it would mostly be automated testing sequences, I imagine.

As 48 hours turnaround won't be needed for a long time I imagine it would mostly be reduction of labour cost as a goal.

[JamesH]

The legs are the single largest pieces of equipment to be attached. An industrial robot can handle them. Maybe humans still make the connections. One step on preparing preflown stages could be handling them with the legs on. Getting the legs off for transport and remounting them got to be one of the more complex, manual labor processes in the flow.

Otherwise it would mostly be automated testing sequences, I imagine.

As 48 hours turnaround won't be needed for a long time I imagine it would mostly be reduction of labour cost as a goal.

Is it worth it? There are only four legs to remove, optimising something that is relatively fast to do anyway might not be cost effective.

Better to leave them on? Why do they take them off anyway?

[JBF]

The legs are the single largest pieces of equipment to be attached. An industrial robot can handle them. Maybe humans still make the connections. One step on preparing preflown stages could be handling them with the legs on. Getting the legs off for transport and remounting them got to be one of the more complex, manual labor processes in the flow.

Otherwise it would mostly be automated testing sequences, I imagine.

As 48 hours turnaround won't be needed for a long time I imagine it would mostly be reduction of labour cost as a goal.

Is it worth it? There are only four legs to remove, optimising something that is relatively fast to do anyway might not be cost effective.

Better to leave them on? Why do they take them off anyway?

Our current guess is that the deployment cylinders are one shots and mechanically lock after deployment.

[JamesH]

The legs are the single largest pieces of equipment to be attached. An industrial robot can handle them. Maybe humans still make the connections. One step on preparing preflown stages could be handling them with the legs on. Getting the legs off for transport and remounting them got to be one of the more complex, manual labor processes in the flow.

Otherwise it would mostly be automated testing sequences, I imagine.

As 48 hours turnaround won't be needed for a long time I imagine it would mostly be reduction of labour cost as a goal.

Is it worth it? There are only four legs to remove, optimising something that is relatively fast to do anyway might not be cost effective.

Better to leave them on? Why do they take them off anyway?

Our current guess is that the deployment cylinders are one shots and mechanically lock after deployment.

Not beyond the capabilities of SpaceX to improve on that then.

[meekGee]

The legs are the single largest pieces of equipment to be attached. An industrial robot can handle them. Maybe humans still make the connections. One step on preparing preflown stages could be handling them with the legs on. Getting the legs off for transport and remounting them got to be one of the more complex, manual labor processes in the flow.

Otherwise it would mostly be automated testing sequences, I imagine.

As 48 hours turnaround won't be needed for a long time I imagine it would mostly be reduction of labour cost as a goal.

Is it worth it? There are only four legs to remove, optimising something that is relatively fast to do anyway might not be cost effective.

Better to leave them on? Why do they take them off anyway?

Our current guess is that the deployment cylinders are one shots and mechanically lock after deployment.

I agree with the guess, but that doesn't mean they can't be folded in place.

Each leg has three structural attach point (all ball joints), and maybe gas lines or electric connections. (I hope each leg has its own internal bottle).

Saving 12 demate/mate operations like that is a major time saver IMO.  The legs are heavy and awkward to handle.

I hope to see them folded on the spot.

[guckyfan]

Each leg has three structural attach point (all ball joints), and maybe gas lines or electric connections. (I hope each leg has its own internal bottle).

Saving 12 demate/mate operations like that is a major time saver IMO.  The legs are heavy and awkward to handle.

I hope to see them folded on the spot.

I hope that too.

However presently the means of transporting the stage requires the legs gone. That's necessary for size restrictions when transported on public highways. It would not be required for moving in the cape area, even from the present mooring location of the ASDS. But new methods of transporting the stage would be needed. I don't know if an ASDS could land the stage at Vandenberg? Probably not because the west coast ASDS is not homed there. So at the west coast the legs would need to be removed for transport on barge landing.

[D_Dom]

Delta Mariner is not home ported at Vandenberg either. Stage deliveries are standard practice. Could be nominal processing.

[meekGee]

Each leg has three structural attach point (all ball joints), and maybe gas lines or electric connections. (I hope each leg has its own internal bottle).

Saving 12 demate/mate operations like that is a major time saver IMO.  The legs are heavy and awkward to handle.

I hope to see them folded on the spot.

I hope that too.

However presently the means of transporting the stage requires the legs gone. That's necessary for size restrictions when transported on public highways. It would not be required for moving in the cape area, even from the present mooring location of the ASDS. But new methods of transporting the stage would be needed. I don't know if an ASDS could land the stage at Vandenberg? Probably not because the west coast ASDS is not homed there. So at the west coast the legs would need to be removed for transport on barge landing.

Yes - in-place leg folding goes hand I  hand with never leaving the cape.

[RoboGoofers]

Would it be impractical to put dollys under the ends of the legs and roll it around? Not back to a building, but to a strongback at the edge of the landing pad, where they could detank and drop to horizontal.

[Dave G]

OK, I'm not sure I remembered this correctly, but I thought I heard something about the possibility of SpaceX using chilled RP-1 in the future, something about increasing both RP-1 and LOX density through chilling.

If I have this right, could chilled RP-1 also make it easier to refurbish the stage? Would chilled RP-1 make the bottom part of the stage look like the middle - all white after landing?

Also, for future SpaceX launchers, would methane make refurbishing easier due to chilled fuel?

Just a thought.

[RoboGoofers]

OK, I'm not sure I remembered this correctly, but I thought I heard something about the possibility of SpaceX using chilled RP-1 in the future, something about increasing both RP-1 and LOX density through chilling.

If I have this right, could chilled RP-1 also make it easier to refurbish the stage? Would chilled RP-1 make the bottom part of the stage look like the middle - all white after landing?

Also, for future SpaceX launchers, would methane make refurbishing easier due to chilled fuel?

Just a thought.

the RP1 was chilled in the last flight, to around ~20 degrees (though i can't remember if it's C or F). it can't go much lower since it would make the RP1 too viscous, and i assume that you need to maintain a proper ratio with the chilled LOx, which can't get any cooler.

methane would make refurb easier, if only because burning it doesn't produce soot.