Author Topic: A capability for crew to change ships in space.  (Read 11568 times)

Offline RDoc

  • Full Member
  • ****
  • Posts: 516
  • Liked: 123
  • Likes Given: 12
Re: A capability for crew to change ships in space.
« Reply #20 on: 10/13/2017 04:29 am »
The cruise ships I've watched dock used tug boats. Agree that a tug boat is not a tender, but it's a distinction without a difference.
Tugs and tenders are totally different. Tugs push ships around, tenders move people from ships to shore, and then then there are lighters which move cargo from ship to shore.

Offline intrepidpursuit

  • Full Member
  • ****
  • Posts: 721
  • Orlando, FL
  • Liked: 561
  • Likes Given: 400
Re: A capability for crew to change ships in space.
« Reply #21 on: 10/13/2017 11:26 pm »
If that port on the side is indeed for docking, which it appears to be in the ISS slide, then it would allow two ships to dock to each other. It would be built into the big cargo door and designed to extend slightly to doc to another vehicle. Ships not planning to dock may just use a simpler hatch if it has any downsides.

I don't see any reason to design and build a new vehicle and launch it on a different rocket beside the two vehicles already in space. It would have to dock with both vehicles anyway so it doesn't even help anything.

Offline speedevil

  • Senior Member
  • *****
  • Posts: 4406
  • Fife
  • Liked: 2762
  • Likes Given: 3369
Re: A capability for crew to change ships in space.
« Reply #22 on: 11/01/2017 07:39 pm »
I don't see any reason to design and build a new vehicle and launch it on a different rocket beside the two vehicles already in space. It would have to dock with both vehicles anyway so it doesn't even help anything.
The argument could be made that it relaxes stationkeeping requirements.
But, it's already required for fuel transfer to work to have stationkeeping to that level of performance.

Offline Oersted

  • Member
  • Senior Member
  • *****
  • Posts: 2892
  • Liked: 4097
  • Likes Given: 2770
Re: A capability for crew to change ships in space.
« Reply #23 on: 11/03/2017 07:59 pm »
If a company can build massive spaceships that fly to Mars in formation, I think we can safely assume it will also have solved the problem of station-keeping and docking between said ships.

Offline Oersted

  • Member
  • Senior Member
  • *****
  • Posts: 2892
  • Liked: 4097
  • Likes Given: 2770
Re: A capability for crew to change ships in space.
« Reply #24 on: 11/03/2017 08:11 pm »
I imagine the docking ports on the BFS will be slightly extensible beyond the outer mold line so two BFS's will be able to dock with each other. Otherwise docking adapters could perhaps be carried in the space between the engine bells and be retrieved in a spacewalk (That sounds complicated, though).

Since the docking ports are squarish, could an adapter perhaps be passed diagonally through the port before being fastened outside? (Referencing the manhole cover question here..)

Offline nacnud

  • Extreme Veteran
  • Senior Member
  • *****
  • Posts: 2691
  • Liked: 981
  • Likes Given: 347
Re: A capability for crew to change ships in space.
« Reply #25 on: 11/03/2017 08:42 pm »
Since the docking ports are squarish...

Looking at the image posted previously the hatch is squarish, the docking port in the hatch is circular. (it looks like a CBM to me, now we can get worked up about berthing vs docking too ;) )

Offline Oersted

  • Member
  • Senior Member
  • *****
  • Posts: 2892
  • Liked: 4097
  • Likes Given: 2770
Re: A capability for crew to change ships in space.
« Reply #26 on: 11/03/2017 11:46 pm »
Ah, no squeezing a docking adapter through the port then!

Berthing is a very sound method, but I think Musk finds it a bit inelegant. If they are going from berthing to docking with the Dragons, I don't see them going back to berthing for BFS's.

Offline Bob Shaw

  • Full Member
  • ****
  • Posts: 1427
  • Liked: 727
  • Likes Given: 676
Re: A capability for crew to change ships in space.
« Reply #27 on: 11/04/2017 12:19 am »
A space-only transfer vehicle could stationed at the ISS for such use. I've always thought it made sense to have such a vehicle as the "buffer" between stations and visiting spacecraft. That way you don't have to compromise on the design of either just to make them capable of docking - like the image of the ITSy docking with the ISS, which I think is unlikely.
Many people noticed the impossibility of certain scenes in "Gravity" where the heroine managed to get from the ISS to the Chinese space station. My thought was: wouldn't it be cool if these manned stations, and maybe more than two, were all in the same orbit, just a few hundred km in front or behind. Then you could shuttle back and forward between them in a Soyuz or similar. We could have exactly that situation with ISS and multiple BFS in orbit. Maybe they never come closer than several kilometers.

I suspect that to move to a station ahead you would thrust down, dipping closer to the earth, rather than directly towards your destination.

It's been done: Mir and Salyut 7, where the Mir crew visited the old space station, picked up equipment, and returned to Mir!

Offline Bob Shaw

  • Full Member
  • ****
  • Posts: 1427
  • Liked: 727
  • Likes Given: 676
Re: A capability for crew to change ships in space.
« Reply #28 on: 11/04/2017 12:31 am »
The cruise ships I've watched dock used tug boats. Agree that a tug boat is not a tender, but it's a distinction without a difference.

A tug is a tug, and a tender is a tender. They are functionally different.

I stand corrected.

Having done night-time boat transfers from a small door in the side of a ship to a tiny tender, dressed up in overalls and life-jacket and hauling Peli cases - let's say that I vote for a nice docking procedure any day. And my experience is 1% of zero-G operations! In short, keep the civilians indoors.
« Last Edit: 11/04/2017 12:32 am by Bob Shaw »

Offline Oersted

  • Member
  • Senior Member
  • *****
  • Posts: 2892
  • Liked: 4097
  • Likes Given: 2770
Re: A capability for crew to change ships in space.
« Reply #29 on: 11/04/2017 04:45 pm »
It's been done: Mir and Salyut 7, where the Mir crew visited the old space station, picked up equipment, and returned to Mir!

Didn't know that story. What a mission!

https://www.airspacemag.com/daily-planet/moving-day-orbit-strange-trip-soyuz-t-15-180959014/

Offline biosehnsucht

  • Full Member
  • ***
  • Posts: 344
  • Liked: 124
  • Likes Given: 319
Re: A capability for crew to change ships in space.
« Reply #30 on: 11/09/2017 07:51 am »
Importantly, they Salyut-7 and Mir were in the same orbital plane, as opposed to all that nonsense in Gravity ...

Offline Darren_Hensley

  • System Software Engineer, MCTP, NGC, Ft Leavenworth Ks
  • Full Member
  • **
  • Posts: 206
  • Captian(ret) USS Pabilli, Timefleet, UFP-TIC
  • Alamogordo NM
    • H-10-K Enterprises
  • Liked: 12
  • Likes Given: 20
Re: A capability for crew to change ships in space.
« Reply #31 on: 11/10/2017 02:47 am »

A space-only transfer vehicle could stationed at the ISS for such use. I've always thought it made sense to have such a vehicle as the "buffer" between stations and visiting spacecraft. That way you don't have to compromise on the design of either just to make them capable of docking - like the image of the ITSy docking with the ISS, which I think is unlikely.


So where is the sense in that?  Now you require all transfers to be done by EVA?  Personnel have to be in suits and items to be transferred have to be able to handle vacuum. Also, have to have airlocks compatible with different EVA suits.  And more suits than are normally would be carried. And everybody trained for EVA.  Oh, and every vehicle would need an airlock.

Jim: I agree mostly with your assessment, However having everyone EVA trained, and having spare EVA suits on hand makes a great deal of sense to me. I agree Transferring vs Docking is senseless unless it's for personnel only and it's a recovery effort to save lives. The only reason to change ships on orbit is to abandon the broken one, and return home or move to a station that can support a rescue mission.

I'm interested in knowing why you would need different airlocks for different suits, just build the airlock to be more universal, and install adapters for the unique interfaces. Better yet develop a standards board like we did with the I-LIDS program, and let everyone use the "international standard" the IEEE works as a great example of cooperation as well...

As for airlocks in the capsules others use now, I say it's time to move towards the universal system, and the sooner the better, lets get it right before we all go beyond earth orbit where rescue missions become more difficult in the near future.

The reason (as I see it) we use airlocks now is because we need to EVA for construction or repair efforts, would a capsule really benefit by adding an airlock? No i think not, the Ingress/EVA hatch works fine while fully suited with PLSS, if needed, but not planned as part of the mission.

JMTC
BSNCM Devry, MAITM Webster, MSSS & MSAP SFA
H-10-K Enterprises Gateway Station

Tags:
 

Advertisement NovaTech
Advertisement Northrop Grumman
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
1