Quote from: Space Ghost 1962 on 03/29/2017 07:31 pmCould this be the simplest lander concept? Something that puts the entire burden of propulsion shortfall on a propulsive stage?Ahem.Quote from: GWH on 02/20/2017 03:14 pmWhy place all the dV requirements for ascent/descent on the lander, and in doing so drive up the requirements on the lander significantly when an upper stage can do the work here? A Xeus-Centaur is at least partly off the shelf, IVF is scheduled to be demo'd in 2018. Investment in that area would have a much greater return IMO then trying to make a capsule perform a 2-way trip. Xeus-ACES might be 5+ off, but Xeus-Centaur could be much sooner.
Could this be the simplest lander concept? Something that puts the entire burden of propulsion shortfall on a propulsive stage?
Why place all the dV requirements for ascent/descent on the lander, and in doing so drive up the requirements on the lander significantly when an upper stage can do the work here? A Xeus-Centaur is at least partly off the shelf, IVF is scheduled to be demo'd in 2018. Investment in that area would have a much greater return IMO then trying to make a capsule perform a 2-way trip.
Gets the Lunar Dragon concept at least to the point where with moderate increases in ISP (canted, partially expanded nozzles) and a large increase in prop meet the ascent requirements.
Quote from: Space Ghost 1962 on 03/29/2017 07:31 pm...., and SX/BO have nothing on the board for this "distraction". Blue does have something on the board, bould be a fit:http://spacenews.com/bezos-and-blue-origin-reportedly-pitch-amazon-like-delivery-for-the-moon/
...., and SX/BO have nothing on the board for this "distraction".
Nope. Masten is tied up with XS-1. ULA is at a point they can't afford any distractions.That's what I was getting at.And why I didn't remark about your earlier comment was that it was too desperate to be believed.It's not about being worthy, it's about having enough operational experience to bring this off. Masten doesn't.There are four US in active use on the globe that can be made to have on orbit lifetimes of weeks. Could be modified for the thermal environment. Can't take this further.
BO's plate is full for the next five years. Note also the game has gone up with the recycling of fairings. There's a few more things to come. And he doesn't have a orbital crew capsule yet. Or a orbital capsule recovery system with precision landing.
One of the simpler ways of dealing with this could be creative use of PAM's, but it is so ridiculous one hesitates to bring it up. No contingencies at all too. Hinted at it earlier because they are still flight qualified for F9/FH.
They all have full plates, so why draw the line at a crash program to modify an LEO capsule to a lunar lander vs a crash program to modify an US to a crasher stage?
Masten is probably too small I agree, however ULA is downsizing so one could argue that they have ALL the necessary resources other than funding.
Quote from: Space Ghost 1962 on 03/29/2017 07:31 pmBO's plate is full for the next five years. Note also the game has gone up with the recycling of fairings. There's a few more things to come. And he doesn't have a orbital crew capsule yet. Or a orbital capsule recovery system with precision landing.Blue Origin didn't have a lot visible for a suborbital rocket and capsule, then one day it was flying.Do you have any insider information on the progress of their biconic capsule?
I've tried researching that on the NASA CRS contracts and came up pretty empty, but that's typical for their level of secrecy. I know they want to use a composite PV that has had assistance but most other support went to New Shep.It isn't realistic to think that they have a complete crew vehicle all ready to go, however without knowing exact progress to date I don't think its fair for outright dismissal of something emerging in a 2-4 year time frame.
Quote from: Space Ghost 1962 on 03/29/2017 07:31 pmOne of the simpler ways of dealing with this could be creative use of PAM's, but it is so ridiculous one hesitates to bring it up. No contingencies at all too. Hinted at it earlier because they are still flight qualified for F9/FH.Please define PAM's? Payload Abort Motors?
Quote from: GWH on 04/01/2017 04:28 pmThey all have full plates, so why draw the line at a crash program to modify an LEO capsule to a lunar lander vs a crash program to modify an US to a crasher stage?Agreed.But the problem is ... what stages?...Payload Assist Module's. Things like Star-48B's. You can find them in the Orbital ATK Propulsion Products Catalog
Boeing released a nice picture at least of a lander
No windows! Bummer!
Quote from: TomH on 04/04/2017 10:29 pmNo windows! Bummer!The windows are on the other side.
Two more images of this lander can be viewed here: http://xp4d.com/gallery.htm#!prettyPhotoSelect the 'Cis-Lunar Missions' tab, 4th row down.
Great work! That 16.7 t to LEO is pretty useful. The Apollo LM was 15 t, so one FH could deploy an LM into LLO, followed by a propulsive Lunar Dragon (LD) into LLO from another FH. LD would then rendezvous with the LM. The mission profile would then follow Apollo. A 9 t lunar habitat would be pretty useful for a two week mission on the surface. SpaceX just needs to extend the kerolox second stage to 3 to 4 days. This was planned for the Soviet N-1/L-3 missions, but never implemented.
Of note...Having seen extended restart capability with FH, we can say an expendable Falcon Heavy should be able to deliver up to 15.2 tonnes direct to GEO.
Quote from: sevenperforce on 02/08/2018 12:53 pmOf note...Having seen extended restart capability with FH, we can say an expendable Falcon Heavy should be able to deliver up to 15.2 tonnes direct to GEO.I get more like 12-13 tons direct to GSO.
Quote from: Steven Pietrobon on 02/06/2018 06:08 amGreat work! That 16.7 t to LEO is pretty useful. The Apollo LM was 15 t, so one FH could deploy an LM into LLO, followed by a propulsive Lunar Dragon (LD) into LLO from another FH. LD would then rendezvous with the LM. The mission profile would then follow Apollo. A 9 t lunar habitat would be pretty useful for a two week mission on the surface. SpaceX just needs to extend the kerolox second stage to 3 to 4 days. This was planned for the Soviet N-1/L-3 missions, but never implemented.Another solution just include third stage using storable propellants which would remove the need for a lot of the design changes on the FH second stage.