Moon Shot - Next Steps

First private sector mission concepts, potential revenue streams, what various companies and organizations are doing along these lines, <b>closely</b> related topics

Moderator: smccann

User avatar
joertexas
Posts: 1021
Joined: Sat Jul 18, 2009 4:44 am
Location: San Antonio Texas

Moon Shot - Next Steps

Post by joertexas » Sun Jan 02, 2011 3:14 am

I've posted some 3D pics of the Orbital Transfer Vehicle here. It will take nine F9/F9 Heavy flights to carry the OTV and its cargo to orbit. Weight isn't the issue, but the components are bulky.

JR

John Hunt
Posts: 568
Joined: Wed Jul 22, 2009 1:17 am

Post by John Hunt » Sun Jan 02, 2011 5:01 am

Why so many Falcon flights? You mix F9s and F9Hs? Can you clarify? Are the yellow components reentry shields. I don't see the blue component in the completed model, What all would the OTV do?

User avatar
joertexas
Posts: 1021
Joined: Sat Jul 18, 2009 4:44 am
Location: San Antonio Texas

Post by joertexas » Sun Jan 02, 2011 5:59 am

[quote=""JohnHunt""]Why so many Falcon flights? You mix F9s and F9Hs? Can you clarify? Are the yellow components reentry shields. I don't see the blue component in the completed model, What all would the OTV do?[/quote]

Well, the parts breakdown shows why so many flights are needed - the components are too bulky to take in fewer flights. Now, if the F9 can handle wider and longer payloads, then the number of flights can be reduced. The F9H will be needed to lift those green O2 tanks for the first OTV, because they will be full (and too heavy for the F9). After the first OTV is up and running, we won't need the F9H to send up the other OTVs, since the fuel will be available on-orbit.

The transparent blue is the interior volume of the F9 and F9H, since the cargo volume is identical for both vehicles. I left it in to represent space for the processing equipment, which will actually be farmed out between all nine flights as room permits. Also, keep in mind that some space and weight will be taken up by braces and such to hold all of this stuff together during launch. I'm also not illustrating things like thermal panels, thrusters, wiring harnesses, and the like. They should fit in the spaces left between the major parts, and I was just trying to get a general idea of the lift needed, anyway.

The yellow is the aerobraking shield, broken into parts to fit in the cargo area. Given the amount of assembly that's needed, we may end up with a small Bigelo module and a crewed Dragon launch to put it all together. At the very least, we will have to have some sort of assembly fixture, whether manned or remotely controlled.

The OTVs will handle all of the equipment and fuel transfers between LEO, E-M L1, LLO, and the lunar surface. I'd like to have four of them up and running, which will cost about $3.5B, but it will also bring in about $2.7B in the first year or so, and net about $1B per year afterwards. These craft would also be capable of handling manned missions in both directions.

JR

User avatar
RaresH
Posts: 227
Joined: Tue Sep 22, 2009 11:40 pm
Location: Dallas, Texas
Contact:

Post by RaresH » Sun Jan 02, 2011 8:32 pm

Very interesting setup Joe.

This is all for the manned mission following the robotic precursor I take it? Yet we only see the OTV equipment here. I hadn't imagined the OTV being so large. What is the cost savings of having the shield sent up as opposed to having longer transfer flights when assuming fuel demands may not be as high to begin with?

Maybe we can reduce the flights for the heat shield by considering an inflatable shield option?; http://www.nasa.gov/topics/aeronautics/ ... /irve.html

Maybe we can manufacture the heat shield on Luna using the silicon extracted from the soil.

Nice Work.

User avatar
Rhyshaelkan
Posts: 615
Joined: Sat Jul 18, 2009 11:16 pm
Location: Michigan, USA

Post by Rhyshaelkan » Mon Jan 03, 2011 6:02 am

Having run a bit of the numbers myself. The delta-v coming back from Luna to LEO can be partially erased by aero-breaking using Earth's atmosphere. Resulting in big fuel savings. Indeed once you get over the hump of EML1 you do not need more thrust to get to Earth. You start falling towards Earth's gravity. To such a degree, that you need to retro burn to be captured correctly. Using a heat shield and aero-breaking results in savings. That leg of the trip is 4400 m/s burn, which can be reduced to 700 m/s burn if Joe is correct. Quite the savings. And every kilo of fuel saved is fuel delivered to LEO. Or fuel used to bring supplies(even human crew eventually) back to Luna's surface.

The heat shield on SpaceX' Dragon, for example, is said to be much more than necessary. So we could reuse the heat shield a few to several times before needing to be replaced. They are not extremely heavy, just bulky, made from aero-gels(if I am not mistaken).
I am not a professional. I am a rational amateur who dreams about humans going into space.
Image

User avatar
joertexas
Posts: 1021
Joined: Sat Jul 18, 2009 4:44 am
Location: San Antonio Texas

Post by joertexas » Mon Jan 03, 2011 6:54 am

[quote=""RaresH""]Very interesting setup Joe.

This is all for the manned mission following the robotic precursor I take it? Yet we only see the OTV equipment here. I hadn't imagined the OTV being so large. What is the cost savings of having the shield sent up as opposed to having longer transfer flights when assuming fuel demands may not be as high to begin with?

Maybe we can reduce the flights for the heat shield by considering an inflatable shield option?; http://www.nasa.gov/topics/aeronautics/ ... /irve.html

Maybe we can manufacture the heat shield on Luna using the silicon extracted from the soil.

Nice Work.[/quote]

After the first Moon Shot mission, we would probably want to send a second survey mission with specialized equipment optimized to assay what we find. Then, the first set of extraction equipment can be built and sent up with the first OTV.

Without the heat shield, the cargo capacity to LEO from L1 is severely reduced, from 83,700kg to 21,000kg. The heat shield should weigh about 3,000kg, so it isn't really worth leaving it off, or making it removable. The problem is that it's really bulky.

I sized the OTV by considering the use of four RL-10 (or CECE) engines. That makes the OTVs powerful enough to carry sizeable loads; 20,500kg to, and 53,000kg from, the lunar surface - such as the processing equipment we'll need.

The inflatable heat shield is a good idea, but the OTVs will have to make up to six trips per year to LEO, with long wait times in between. I'm not certain an inflatible device is that durable. Manufacturing shields is something that I'd like to do, but anything that we make will have to be tested first - and we have to have the manufacturing facilities to make it.

JR

User avatar
joertexas
Posts: 1021
Joined: Sat Jul 18, 2009 4:44 am
Location: San Antonio Texas

Post by joertexas » Mon Jan 03, 2011 7:02 am

[quote=""Rhyshaelkan""]Having run a bit of the numbers myself. The delta-v coming back from Luna to LEO can be partially erased by aero-breaking using Earth's atmosphere. Resulting in big fuel savings. Indeed once you get over the hump of EML1 you do not need more thrust to get to Earth. You start falling towards Earth's gravity. To such a degree, that you need to retro burn to be captured correctly. Using a heat shield and aero-breaking results in savings. That leg of the trip is 4400 m/s burn, which can be reduced to 700 m/s burn if Joe is correct. Quite the savings. And every kilo of fuel saved is fuel delivered to LEO. Or fuel used to bring supplies(even human crew eventually) back to Luna's surface.

The heat shield on SpaceX' Dragon, for example, is said to be much more than necessary. So we could reuse the heat shield a few to several times before needing to be replaced. They are not extremely heavy, just bulky, made from aero-gels(if I am not mistaken).[/quote]

The Delta Vee from E-M L1 to LEO is 3.77 km/s. Aerobraking can reduce that by 3.0 to 3.2 km/s, depending on whose numbers you believe.

The reason this is so important is the amount of fuel and other materials we can deliver to LEO - and get the OTV back to L1 or the lunar surface again. Even if the heat shield weighs twice as much as I'm predicting, it will still be worthwhile to haul it around. It would help a little to have it be removable, but not enough to be worth the extra complexity, IMO.

Of course, everything about all of the designs I've proposed is subject to revision once the real engineers start working on it ;)

JR

User avatar
joertexas
Posts: 1021
Joined: Sat Jul 18, 2009 4:44 am
Location: San Antonio Texas

OTV Engine Report

Post by joertexas » Tue Jan 04, 2011 6:32 am

It's amazing what you can find on the Internet :D

This one will take a while to digest.

JR

John Hunt
Posts: 568
Joined: Wed Jul 22, 2009 1:17 am

Post by John Hunt » Sun Jan 22, 2012 3:28 am

Forgive me for asking this question this far down the line...but is the Moon Shot just the prospecting aspect or the whole lunar ice mining operation including the prospecting part? If it is the latter, then can you direct me to a good summary write-up of the whole concept or can you now write up that summary now if fine for public discussion?

Post Reply