Quote from: Paul451 on 03/30/2016 04:36 am{snip}As I said, I like the imagery of a space garage. I just don't see the point of it in a "minimalist" or near-term architecture. Sure, once you have ten landers operating around the clock (or which two or three are in service/repair/upgrade at any given time) then it might make sense to have a central facility in lunar orbit (or at a Lagrangian staging point), and if you are pretty much constantly repairing some of the landers, it makes sense (IMO) to have an unpressurised enclosure to simplify EVAs. But when you only have one or two landers and, say, four flights a year, or similar realistic near-term flight rates, it just doesn't make sense.{snip}This is asking a major high level question - are the landers expendable (single use) or reusable and serviced/replaced in space?
{snip}As I said, I like the imagery of a space garage. I just don't see the point of it in a "minimalist" or near-term architecture. Sure, once you have ten landers operating around the clock (or which two or three are in service/repair/upgrade at any given time) then it might make sense to have a central facility in lunar orbit (or at a Lagrangian staging point), and if you are pretty much constantly repairing some of the landers, it makes sense (IMO) to have an unpressurised enclosure to simplify EVAs. But when you only have one or two landers and, say, four flights a year, or similar realistic near-term flight rates, it just doesn't make sense.{snip}
A lunar orbiting spacestation is likely to have [...] an escape pod of some sort
{snip}Escape pods aren't a thing in space; only in SF.
Quote from: A_M_Swallow on 03/31/2016 03:49 amQuote from: Paul451 on 03/30/2016 04:36 am{snip}As I said, I like the imagery of a space garage. I just don't see the point of it in a "minimalist" or near-term architecture. Sure, once you have ten landers operating around the clock (or which two or three are in service/repair/upgrade at any given time) then it might make sense to have a central facility in lunar orbit (or at a Lagrangian staging point), and if you are pretty much constantly repairing some of the landers, it makes sense (IMO) to have an unpressurised enclosure to simplify EVAs. But when you only have one or two landers and, say, four flights a year, or similar realistic near-term flight rates, it just doesn't make sense.{snip}This is asking a major high level question - are the landers expendable (single use) or reusable and serviced/replaced in space? It's not. Nothing I said assumed expendable landers.There is no reason for a orbital "garage" when talking about an architecture with only one or two -- reusable! -- landers and a small handful of missions per year.There's no stockpile of fuel requiring a depot, you refuel the landers directly. The incoming fuel supply is the "depot".There's no stockpile of parts. The parts travel with the crew doing the repair mission.And the mission hardware, such as the crew capsule, simply docks directly with the lander for crew transfers.QuoteA lunar orbiting spacestation is likely to have [...] an escape pod of some sortEscape pods aren't a thing in space; only in SF.
Quote from: Paul451 on 04/03/2016 10:09 amEscape pods aren't a thing in space; only in SF.The ISS could be SF.Dragon and CST-100 will be able to act as escape pods.
Escape pods aren't a thing in space; only in SF.
A lunar orbiting spacestation is likely to have a couple of landers, one or two manned spacecraft from Earth, an escape pod of some sort [...]
To perform major repairs the crew capsules would need to have robotic arms.
Any EML1 based reusable lander can act as an escape pod. Having a 2nd lander at EML1 would allow rescue of crew from anywhere between LEO and lunar surface. With 6-7km/s DV it can easily reach ISS from EML1 if return capsule is faulty.
Quote from: A_M_Swallow on 04/03/2016 02:22 pmQuote from: Paul451 on 04/03/2016 10:09 amEscape pods aren't a thing in space; only in SF.The ISS could be SF.Dragon and CST-100 will be able to act as escape pods.Your original list of ingredients had:QuoteA lunar orbiting spacestation is likely to have a couple of landers, one or two manned spacecraft from Earth, an escape pod of some sort [...]You were clearly talking about an escape pod that is distinct from the normal manned capsules.And that is not a thing. Won't be until we have true space-ships.
Quote from: A_M_Swallow on 04/03/2016 02:25 pmTo perform major repairs the crew capsules would need to have robotic arms.Not really. A lander is not a space-station.
I created the thread to discuss a minimalist lunar architecture based on FH with Raptor US. You guys are getting way beyond minimalistic. The whole idea was to create an affordable architecture, not to see if we could give it NASAesque complexity. Please bring the discussion back within the parameters.
Quote from: TrevorMonty on 04/03/2016 05:07 pmAny EML1 based reusable lander can act as an escape pod. Having a 2nd lander at EML1 would allow rescue of crew from anywhere between LEO and lunar surface. With 6-7km/s DV it can easily reach ISS from EML1 if return capsule is faulty.Did you take into account what ISS inclination does to the delta-v requirement of reaching it?
You need to define minimalistic.
If we do not have a spacestation than the repair arms for the landers have to go on the transfer vehicles (crew capsules). The Space Shuttle used its arm to repair the Hubble Telescope.
using Trunk-based crasher stages
Anyone know the current delta-vee for a Dragon Version 2?
Agreed about the Kestrel. I only mentioned a Trunk based Crasher stage because someone more qualified and connected than me has mentioned it elsewhere before.
Quote from: TomH on 04/05/2016 01:22 amI'd suggest a more generally paraphrasing, you're asking "what's a lowest cost manned landing on the moon"?Quote from: A_M_Swallow on 04/04/2016 10:30 amIf we do not have a spacestation than the repair arms for the landers have to go on the transfer vehicles (crew capsules). The Space Shuttle used its arm to repair the Hubble Telescope.The primary purpose of the arms is to move large payloads, or to relocate large modules around the ISS. A secondary function was as a handy base for astronauts to work from.However, for a lander and capsule docked together, the primary function of the robot arm is not necessary. By including a large space-station, you merely increase the costs and the number of systems that need repair.Repairs to a lander would be carried out internally, passing through the docking adaptor, and externally via EVAs conducted using various handle and attachment points build into the lander, using the capsule as an airlock.You're confusing how things can be done with how they must be done.