copernicus - 7/5/2006 12:14 AM
Also, should NASA be working more urgently in the next year on the specifics
of the LSAM in order to start requesting some RFI's (Requests for Information)
from industry?
Bill White - 8/5/2006 2:19 PMQuotecopernicus - 7/5/2006 12:14 AMAlso, should NASA be working more urgently in the next year on the specifics of the LSAM in order to start requesting some RFI's (Requests for Information) from industry?This weekend's official announcement of funding for the X Prize lunar hopper challenge suggests to me that NASA may desire to learn whether truly re-useable rocket engine technology can be developed by some of these little guys (and then bought up by a big guy?) before LSAM design gets too far down the road.A totally re-useable LSAM (lunar LOX together with well just about anything) will be critical to sustained lunar exploration.Those XCOR rocket racers may seem like a toy until you realize those engines will start and stop very very frequently.
copernicus - 7/5/2006 1:14 AMHas anyone heard any updates on the configuration of the LSAM? Will it need to be modified from the ESAS design as a result of CaLV payload restrictions, or does the recent re-work of the CaLV (10-m diameter first and second stages) allow it to maintain its original weight and specifications? Also, should NASA be working more urgently in the next year on the specifics of the LSAM in order to start requesting some RFI's (Requests for Information) from industry?
Under terms of the contract, ATK will design, develop, fabricate, test, and evaluate a 7500-lbf constant-thrust, pressure-fed bipropellant rocket engine assembly using Liquid Oxygen and Liquid Methane. The first phase of the development is to design and test a heavy-weight, prototype rocket motor. Upon completion, the contract allows for options to design and fabricate a more flight-weight prototype engine. Production variants of this main engine will have multiple restart capabilities to support lunar exploration as well as additional exploration to Mars. This contract is designed to develop new technologies that raise the Technology Readiness Level (TRL) and determine the feasibility of producing a main engine.
XCOR, a Mojave California-based rocket engine development firm, will provide engineering design and testing support to NASA and ATK throughout the development process.
Bill White - 8/5/2006 2:39 PMAn announcement concerning LOX/methane engine development. XCOR is involved.Under terms of the contract, ATK will design, develop, fabricate, test, and evaluate a 7500-lbf constant-thrust, pressure-fed bipropellant rocket engine assembly using Liquid Oxygen and Liquid Methane. The first phase of the development is to design and test a heavy-weight, prototype rocket motor. Upon completion, the contract allows for options to design and fabricate a more flight-weight prototype engine. Production variants of this main engine will have multiple restart capabilities to support lunar exploration as well as additional exploration to Mars. This contract is designed to develop new technologies that raise the Technology Readiness Level (TRL) and determine the feasibility of producing a main engine.XCOR, a Mojave California-based rocket engine development firm, will provide engineering design and testing support to NASA and ATK throughout the development process.Hypergolic fuels are a dead end both for ISRU and re-useability and ten years seems a fairly good lead time to develop LO2 extraction techniques from lunar regolith. As for a parking place, a re-useable LSAM could perhaps station keep at EML-1, no space station needed, although Boeing has issued some lovely L1 architectures based on building stations.
Jim - 8/5/2006 3:08 PM
Just a point, the architecture in ESAS will be used a while until 202X or so before any changes for exploitation are done
Great (and early) ideas are coming forth about the LM for CEV. The development of the CEV
LM would start about 2009-2010. One concept (that will be published next year) is for a LCCL
(Lunar Crew/Cargo Lander). The LCCL is about 2.5 times the length of an Apollo LM and ruffly
the same hight. It has an external airlock/crewlock not part of but soft mounted to the aft of the
Assent stage. Access to the Lunar surface is via the crewlock at the aft end of the Assent
stage. The crewlock will stay on the surface fixed to the decent stage when the crew departs.
Along with crew equipment, surface operations support hardware, Lunar EVA spacesuits and
other high value items could be left behind in the crewlock for reuse or to serve as a source of
spares parts for future expeditions (several US spacesuits on ISS failed when a build of
biomass clogged fans and pumps).
The cargo version would have a crew habitat in place of the assent stage and the same
crewlock. Tanks for holding fuel what instead hold water. Solar power and battery systems
would initially provide power to the LCCL habitat. Future power could be provided by a Lunar
Surface Reactor (based on research done at MSFC). The cargo variant could have 6 legs.
The lander has a 3 engines with a single engine out capability. Heavy cargo would be flown in
place of the habitat. Cargo variants LCCL would not need a CEV for leaving Earth orbit or
landing on the moon. The real thing may never look like this, but it's fun read about new
designs.
Jim - 8/5/2006 1:21 PMQuotecopernicus - 7/5/2006 1:14 AMHas anyone heard any updates on the configuration of the LSAM? Will it need to be modified from the ESAS design as a result of CaLV payload restrictions, or does the recent re-work of the CaLV (10-m diameter first and second stages) allow it to maintain its original weight and specifications? Also, should NASA be working more urgently in the next year on the specifics of the LSAM in order to start requesting some RFI's (Requests for Information) from industry?
LSAM is on the back burner. Order of work prority:
1. CEV
2. CLV
3. CaLV
4. LSAM
Sure, some LSAM requirements work has to be done up front, but the CEV must get selected and have its requirements settle out.
Kayla - 21/5/2006 4:22 PM
I understand that this is NASA's priority, but does it make sense. CEV must be the number 1 priority, or we don’t have an American human space program. But from a risk perspective, the LSAM is right at the top. This is the machine that if it doesn’t work, astronauts die! At least with launch vehicles (other than shuttle) the CEV can abort with a strong likelihood of the astronauts surviving. Also, no one has developed a lunar lander since the 1960’s. This presents us with a huge experience gap.
nacnud - 29/5/2006 7:20 PM The big step you are missing is, what transfer vehicle?
I know, it was just a hypothetical question.
lmike - 21/5/2006 6:33 PM
"CEV must be the number 1 priority, or we don’t have an American human space program." I think there is a weakness even in this proposition. The way it is right now, the CEV/CLV is a dependent pair. Both must have equal priority, or we'll have nothing to launch that CEV on. Or, alternately, we'll have nothing to launch on the CLV. As it is the CEV is tied onto the specific CLV. Architecturally(sp?). A smaller CEV with a 'universal' interstage adapter would fit better into this sequence.
lmike - 16/6/2006 7:45 AM
I understand. My point was that the CEV as planned "needs" the CLV (as planned) in terms of mass, interfaces, diameter and abort profiles. It's a pair made for each other (from the same exploration office). If one doesn't "like" the CLV (as planned), then one doesn't like the CEV (as planned) for important parameters like mass and interfaces. (Sure, the EELVs with enough $$$ could be made to mimic the CLV as substitutes, but why settle for a half solution?! we need to make the whole approach better.) The Big Gemini was a lot lighter than the CEV did the same thing, and could fit on a variety of rockets with thrust (throttle) control.
Jim - 16/6/2006 5:15 AM
Big Gemini is not lighter. Most of the weight in the CEV is fuel for the TEI. Just as the BG could fly on many LV's so can the CEV, both would have to be optimized for the specific mission. There is nothing special or magically about the BG that gives it any advantage over the CEV. Anyways the BG was a paper study and systems that only exist on paper can do "anything". It just takes a pencil and eraser.
lmike - 16/6/2006 8:43 AM
I believe you misunderstood. The BG (as planned) was to be a lighter *Earth descent vehicle* Irregardless of the Moon missions. The CEV (as planned) has a heavier *Earth descent vehicle* for little (explained) reason.
I don't have a problem with the CEV's configuraion, just the mass of the CM.
lmike - 16/6/2006 8:34 AMQuoteJim - 16/6/2006 5:15 AM
Big Gemini is not lighter. Most of the weight in the CEV is fuel for the TEI. Just as the BG could fly on many LV's so can the CEV, both would have to be optimized for the specific mission. There is nothing special or magically about the BG that gives it any advantage over the CEV. Anyways the BG was a paper study and systems that only exist on paper can do "anything". It just takes a pencil and eraser.
The CEV as it stands in its PowerPoint slides and cardboard mock-ups, cannot fly on "many LVs" (without modification, but isn't that the point?) Just the CLV. It's way to heavy (to fit the CLV's launch profile). Btw, it’s also in the pencil and eraser stage. At least the BG had an operational predecessor.
lmike - 16/6/2006 9:06 AM
Ok, fine. ;) I just think that the CEV was tailor made for the pre-selected CLV. That was A Bad Thing. We should have made a CEV that fits on a variety of the existing (with no modifications) CLV's. That would be Good. 'Kay?