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.
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.
Since the docking ports are squarish...
Quote from: Coastal Ron on 10/10/2017 09:13 pmA 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.
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.
Quote from: Coastal Ron on 10/12/2017 04:55 amQuote from: aero on 10/12/2017 02:13 amThe 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.
Quote from: aero on 10/12/2017 02:13 amThe 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.
It's been done: Mir and Salyut 7, where the Mir crew visited the old space station, picked up equipment, and returned to Mir!
Quote from: Coastal Ron on 10/10/2017 09:13 pmA 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.