I had this thought while reading the various escape system threads and proposals to use Dragon.I expect most of us here read or have read science fiction. In those novels the large ships always have a hanger bay of various sizes...
The BFS doesn't need an attack shuttle but sleds capable of transporting a single suited astronaut from the BFS to the ISS might be useful. The BFS station keeps near the ISS then NASA astronaut rides the sled over, secures it temporarily outside the ISS and enters the ISS via the same air lock used for space walks. Small items may be attached to the sled for return to the BFS and Earth before the sled is released to automatically home on the BFS and re-enter the hanger bay.
The same sleds might be useful during transit to Mars, especially in a medical emergency where the proper specialist is on the wrong ship. Of course the range of the sled would be limited so its usefulness in transit depends on how closely the transiting fleet can fly in formation.Other common uses for such sleds include search and recovery of crew forced to abandon a ship of the fleet, redistribute the recovered crew throughout the fleet, and to visit artifacts drifting in a reachable trajectory. Of course the capabilities of the science fiction sleds increases with the author's imagination but we're pretty imaginative here on NSF, and some even with the appropriate experience to flesh out this idea, if it is found worthy.
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.
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.
How about a cylindrical pod that fits entirely inside the airlock space shown on the BFS? With an IDA at each end of the cylinder, some open cycle life support, GNC, and minimal propulsion, it could eject from the BFS and dock with another BFS, Dragon 2, or ISS.It wouldn't be very large, perhaps ~1.2m in diameter and ~3m long, big enough for 2 or 3 people for a few hours.It could also function as both an airlock and a docking port while normally mated inside BFS. I think BFS will need both an airlock and a docking port anyway, so this fills three needs with one item.
Quote from: envy887 on 10/11/2017 06:21 pmHow about a cylindrical pod that fits entirely inside the airlock space shown on the BFS? With an IDA at each end of the cylinder, some open cycle life support, GNC, and minimal propulsion, it could eject from the BFS and dock with another BFS, Dragon 2, or ISS.It wouldn't be very large, perhaps ~1.2m in diameter and ~3m long, big enough for 2 or 3 people for a few hours.It could also function as both an airlock and a docking port while normally mated inside BFS. I think BFS will need both an airlock and a docking port anyway, so this fills three needs with one item.My assumption is that the docking port collar would be extendable somewhat, to allow two BFS' to dock together. Either aligned, or rotated 90 degrees.
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.
Quote from: Jim on 10/11/2017 01:52 pmQuote 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.I never mentioned EVA's, I said "a space-only transfer vehicle".Think of something like a human-rated Cygnus that is designed to just shuttle between the ISS and a visiting BFR or other large spacecraft - actually any two vehicles or stations that are in close vicinity. An Earth analogy would be a tender, which is used to transport people and/or supplies to and from shore or another ship.It simplifies the situation of having to design vehicles that can mate by eliminating the need to mate, all they need are common docking ports - NO EVA's REQUIRED. Plus it reduces the chances of docking collisions between large vehicles and stations.
not really
a. if they have common docking ports for the space-only transfer vehicle, then they can dock
b. Designing for docking doesn't really comprise the design. docking isn't really much more than rendezvous
c. Cruise ships prefer docking at a pier vs using tenders
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.
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.