Post central for information on CEV - iformation station for the spacecraft

SpaceNut · 2004-07-28 12:31:24

I do not know if others are interested but there are a series of articles being presented by guess writers on the Project Constellation site about the CEV.
http://www.projectconstellation.us/news/

clark · 2004-07-30 09:08:31

http://www.upi.com/view.cfm?StoryID=200 … 4356-2684r

Read for yourself...

WASHINGTON, July 29 (UPI) -- Inside NASA, planners have begun to assemble teams that are looking deep inside President George W. Bush's new vision of space exploration. Their goal: define the characteristics of the first new piloted spaceship since the space shuttle, and establish the initial steps and stages by which these new craft will attempt a series of moon landings.
Inside NASA's Exploration Mission Directorate, a requirements group is busily working to put substance into the new assault on the moon.
What are NASA's requirements for the new moonship? According to Mike Lembeck, who heads the requirements group, they compose a soup-to-nuts catalog of everything moonwalking astronauts will need on their initial forays: How big will the ships be? How many astronauts will they carry? How will their launching rockets get them there? When they get to the moon, what will be the profiles of their explorations, and what science will they seek?
Soon, the planners will call upon industry to start designing the ships.
"We hope to get an RFP (request for proposal) out by January on the CEV (crew exploration vehicle), and have a fly-off of two teams in 2008," Lembeck said.
The fly-off, a staple of contracting for military aircraft, will be new to NASA's manned space efforts.
Lembeck described a process by which the space agency will choose a pair of teams, each with a complete design for the CEV, its booster rocket, and the method by which it would achieve Earth orbit and become part of a manned moon flotilla.
Each contractor-led team would include subcontractors that would provide the moonbound astronauts with equipment, life support, rocket thrusters and onboard navigation systems. The Earth orbit fly-offs would pit one complete design against another, with NASA choosing the winner, who would build the final ships.
Reusability is likely to be a valuable component, but initially not essential, Lembeck said. Rather, it is what makes the most sense in designing the 21st century lunar craft.
Lembeck's group released an initial study request last month to begin gathering issues and potential needs for the spaceships, clearing the path so the actual contract request in January can be more focused. They want the moon version of the CEV to contain systems that can be evolved to sustain deeper trips into space, such as voyages to asteroids or manned flights to Mars.
Right now, however, the shape of the craft is not a main priority.
"We aren't focused on the mouldline," Lembeck said, only what needs to be inside. Current thinking, he said, is the lunar CEV might be sized for four astronauts -- the Mars ship for six.
"We are thinking in terms of two-person teams for EVAs," he explained. EVAs, or spacewalks, would be designed around a minimum of two astronauts outside at a time. Studies will also determine by the end of this year if the CEV and the lunar lander will be separate spacecraft, or if they can be combined into a single ship. The current thinking by mission planners is attempting a single lunar landing per year, starting no later than 2020, but perhaps as early as 2017.
Lembeck said NASA is planning to have the fly-off winner design the CEV ships in a series of "spirals," or complete packages of spacecraft systems and subsystems:
-- Spiral one would comprise the early CEV capable of carrying crews into orbit for testing flights.
-- Spiral two would consist of true moonships, able to stay on the moon from a few days to a week.
-- Spiral three would be the most capable ships, which could extend human presence on the moon up to three months, basically establishing an initial lunar base.
NASA planners currently are focusing on a three-part plan to return to the moon that they call trade studies.
During Project Apollo in the 1960s and '70s, astronauts flew into Earth orbit aboard a giant Saturn V rocket carrying an Apollo command ship and a separate landing craft. The top stage of the rocket blasted the lunar duo to the moon, where the lander detached from the capsule mothership and descended to the surface, remaining there for up to nearly three days.
The first return flights under the new plan would strongly resemble the most advanced Apollo missions.
"These first missions would follow a minimalist approach," Lembeck said. They might employ separate transfer and landing systems, carrying the spaceship elements together until moon orbit, as did Apollo, then detaching for landing at relatively safe locations along the moon's equator. Astronauts would then stay on the surface for up to a week's duration.
The second wave of flights would be more complex. The elements for the flight actually might be assembled at the L-1 point -- the Lagrange point, about 200,000 miles up, at which the gravitational influences of the Earth and the moon cancel each other out.
Following assembly at L-1, the craft then would embark toward the moon, following a flight path that would cover virtually all of the moon's regions and allowing landings in more scientifically interesting, but more potentially hazardous, locales. Stay times would also average as long as a week.
The third wave would consist of the most ambitious missions currently being considered. These would require the most capable CEVs and landers, with their components assembled either in low Earth orbit or at L-1. The ships would land at the moon's poles, establish base camps, and stay 45 days and longer. These outposts then would become the first U.S. lunar bases.
Lembeck noted that astronauts on these later missions would bring equipment and tools that would be needed on a Mars outpost, making the first moon bases the testing grounds for the Mars assault.
While planners already are addressing CEV and moon-mission designs, a team of researchers at NASA's Goddard Spaceflight Center in Greenbelt, Md., is completing an initial review of the scientific objectives of the landings. For the return to Earth, the directorate is studying various types of configurations, including a rocket-assisted setdown on land, like the Russians use on their Soyuz capsules. Another option involves descending directly to Earth from moon orbit, as did the Apollo astronauts. The teams are studying the moonship's launching rockets as well.
Lembeck said these reviews include the size of the boosters, the methods by which the astronauts could escape a launching accident, and whether an engine loss could be sustained and still allow the flight to continue.
The planners also are reviewing the entire suite of space equipment, including new designs for spacesuits, habitats that could be built on the surface, what crews would need to construct them and the kinds of robots they would need to accompany them on their traverses across the moon's rocky terrain.
For longer journeys into space, however, future astronauts will need a whole new kind of rocket power -- and the means to generate power as well.

SpaceNut · 2004-07-30 09:51:04

Thanks Clark: on the UPI exclusives from spacedaily and UPI Press. Both articles quote in the form of questions the requirements for Moon and Mars with broad opening statements of the type of crafts to expect.

I find it odd that the spacedaily page shows the Kistler rocket, are they not aware of the contract being cancelled.

The fly off was discussed by many of us months ago. If in the process of the fly off if it should happen to be made a man rated event. I would not be against the 2008 as the target date.

The second wave of flights could be more complex with elements for the flight actually being assembled at the L-1 point. This only makes sense if there is a station there to construct the elements into something otherwise it is probably not worth doing.

By years end differing studies will also determine if the CEV and the lunar lander will be separate spacecraft, or if they can be combined into a single ship much like the apollo program.

clark · 2004-07-30 13:45:47

I am reposting this, as it follows along this thread a bit more. This is brought from the ISS cutbacks thread in Sciecne and Technology:

http://www.newmars.com/forums/viewtopic … ...ntry111

Robert Dyck wrote this:

Ah. According to Encyclopedia Astronautica the Shuttle can lift 27,500kg to 204km orbit @ 28.5° inclination, or 16,050km to ISS. Launch vehicles like Atlas V or Delta IV are usually quoted to 185km orbit since that's the lowest usable orbit, therefor greatest mass (looks good on a sales glossy). According to NASA the Shuttle can lift 28,803kg to LEO, which I assume is the same 185km orbit. So using that figure we get a ratio of 16050/28803 = 0.5572336 which means a pentalty of 100% - 55.72336% = 44.27664%. That sounds even worse than GCNRevenger suggested. However, Shuttle has to carry the mass of its orbiter as well as payload so add 104,326kg end-of-mission mass. The total orbiter + payload to 185km is 28803 + 104326 = 133129kg. The total to ISS = 16050 + 104326 = 120376. The ratio is then 120376/133129 = 0.9042057 or a pentalty of 100% - 90.42057% = 9.57943%. I think last time I estimated Atlas V 401 lift I had used Proton figures, but let's see what this one gives us:
vehicle - price - LEO - ISS
Atlas V 401 - $77M - 12,500kg - 11,302.57kg
Atlas V 501 - $110M - 10,300kg - 9,313.3kg
Atlas V 551 - $170M - 20,050kg - 18,129.3kg
Delta IV Medium - $90M - 8,600kg - 7,776kg
Delta IV Medium+ (4,2) - $95M - 11,700kg - 10,579kg
Delta IV Medium+ (5,4) - $110M - 13,600kg - 12,297kg
Delta IV Large - $170M - 25,800kg - 23,328.5kg

Which led me to this:

Robert, those numbers made me think...

Anyone have any thoughts on this:

Updated Gemini as the basis for a CEV design.

http://www.astronautix.com/project/gemi … gemini.htm

http://www.astronautix.com/craft/gemini … gemini.htm

Crew Size: 2. Length: 3.35 m. Basic Diameter: 2.32 m. Maximum Diameter: 2.32 m. Habitable Volume: 2.55 m3. Mass: 1,983 kg. Structure Mass: 638 kg. Heat Shield Mass: 144 kg. Reaction Control System: 133 kg. Recovery Equipment: 98 kg. Navigation Equipment: 63 kg. Telemetry Equipment: 51 kg. Electrical Equipment: 126 kg. Communications Systems: 26 kg. Crew Seats and Provisions: 426 kg. Crew mass: 144 kg. Miscellaneous Contingency: 100 kg. RCS Fine No x Thrust: 16 x10kgf. RCS Propellants: N2O4/MMH. RCS Isp: 283 sec. RCS Impulse: 9,226.19 kgf-sec. Main Engine Propellants: N2O4/MMH. Main Engine Propellants: 33 kg. Main Engine Isp: 283 sec. L/D Hypersonic: .16. Electrical System: Batteries. Electric System: 4.0 kWh. Battery: 180.0 Ah.

Update it with new materials, perhaps reducing the weight somewhat, and make it a little lagrer to accomdate 4 people (assume 100% increase in mass size and it is well within EELV)

http://www.astronautix.com/craft/gemelt … melter.htm

Use the "modular" approach with this version of the gemini and we have a temporary lunar base...

I might add that Jeff Bezos Blue Origin group has been rumored to be developing a 7 person sub-orbital/low earth orbit space ship (named New Shepard) based on the Gemini.

clark · 2004-07-30 14:20:53

Take a look at this:

http://www.astronautix.com/articles/byg … gemoon.htm

A Personal Postscript
Not considered at the time, but truly having the potential for a reduced-cost, reduced-risk program would have been a purely Titan-based, USAF-managed project. By using earth-orbit rendezvous and Titan 2 and Titan 3C as the launch vehicles, a program can be constructed that would have landed an American on the moon much earlier than Apollo. With a 2,500 kg open-cockpit LM the moon landing could be accomplished using only two Titan 3 launches: one a Titan 3E, putting a Centaur upper stage into low earth orbit; the other a Titan 3D, putting a Lunar Gemini-LM combination into low earth orbit, which would dock with the Centaur and then proceed to the moon. Such a program, taking into account the actual Gemini and Titan 3C development schedules, would have looked something like this:

Apr 1964 Gemini 1 Titan 2 Unmanned booster orbital test; boilerplate spacecraft.
Jan 1965 Gemini 2 Titan 2 Unmanned suborbital test of spacecraft
Mar 1965 Gemini 3 Titan 2 Manned orbital
Jun 1965 Gemini 4 Titan 2 4-day manned orbital
Jun 1965 Gemini L-1 Titan 3C First test flight of Titan 3C; unmanned lunar flyby
Aug 1965 Gemini 5 Titan 2 8-day manned orbital
Oct 1965 Gemini L-2 Titan 3C Unmanned lunar flyby test; Transtage exploded
Dec 1965 Gemini 7 Titan 2 14-day manned orbital
Dec 1965 Gemini 6 Titan 2 Rendezvous with Gemini 7 (Agena target failed to orbit)
Dec 1965 Gemini L-3 Titan 3C Unmanned lunar flyby
Mar 1966 Gemini 8 Titan 2/Atlas-Agena Agena docking
Jun 1966 Gemini 9 Titan 2/Atlas-Agena Agena docking
Jun 1966 Gemini L-4 Titan 3C Manned lunar flyby
Aug 1966 Gemini 10 Titan 2/Atlas-Agena LM docking
Aug 1966 Gemini L-5 Titan 3E Titan 3E test; unmanned; failure
Oct 1966 Gemini 11 Titan 2/Atlas-Agena LM docking
Nov 1966 Gemini L-6 Titan 3E Unmanned lunar orbiter
Jan 1967 Gemini L-7 Titan 3E Manned lunar orbiter
Apr 1967 Gemini L-8 Titan 3E/Titan 3D Manned earth orbit rendezvous, lunar orbit, LM descent
Jul 1967 Gemini L-9 Titan 3E/Titan 3D First landing on moon
Such a program could have achieved a manned lunar landing two years earlier than Apollo at half the cost, a savings of $ 9 billion.

Here are the specs on the titan 3E:

http://www.astronautix.com/lvs/titan3e. … itan3e.htm

Titan 3D with Centaur D-1T upper stage. Used by NASA for deep space missions in 1970's. Launches: 7. Failures: 1. Success Rate: 85.71% pct. First Launch Date: 11 February 1974. Last Launch Date: 05 September 1977. Launch data is: complete. LEO Payload: 15,400 kg. to: 185 km Orbit. Payload: 3,700 kg. to a: TransMars trajectory. Apogee: 400,000 km. Liftoff Thrust: 1,079,550 kgf. Liftoff Thrust: 10,586.80 kN. Total Mass: 632,970 kg. Core Diameter: 3.05 m. Total Length: 48.00 m. Launch Price $: 29.30 million. in 1974 price dollars. Flyaway Unit Cost $: 72.50 million. in 1985 unit dollars.

These specs are well within an updated Gemini flying on EELV.

clark · 2004-07-30 14:36:15

How about the "Big G"?

http://www.astronautix.com/craft/bigemi … gemini.htm

Big G would consist of the following modules:

Launch escape tower - the LES developed for the Apollo program would be used for Big-G.
Big G re-entry module - This was based on the Gemini B re-entry module developed for the USAF MOL program. The Gemini B's fully integrated flight cockpit, environmental control system, and electronic system installations would be retained. However the Gemini B re-entry module conical structure would be extended to 154 inches (3.91 m) diameter (the same as the Apollo service module) to provide a large passenger compartment. This compartment could accommodate up to ten additional passengers or a mix of passengers and cargo - a capacity over twice as great as the Apollo command module at the same total re-entry vehicle mass. The standard configuration proposed for NASA had a crew of six plus substantial cargo return capability. The environmental control system for the passengers and the communication system were located under the floor of the passenger compartment. The existing hatch in the Gemini-B bulkhead would be retained to allow the pilot and co-pilot access to the passenger compartment.
Retrograde module - This module, tapering from 154 inches to 180 inches (4.57 m) diameter at its base, would house the solid fuel de-orbit rocket motors, separation rockets, and water and oxygen supplies.
Manoeuvring and cargo module - This module included propulsion for orbital manoeuvring, electrical power, pressurised and unpressurised volumes for cargo, a pressurised pass-through tunnel, an Apollo docking probe assembly, and a control station for controlling the docking manoeuvre. Unlike Gemini or Apollo, Big G would dock by its aft end with the space station (the same approach was used in the Soviet TKS resupply spacecraft). This module would vary greatly in size and mass according to the launch vehicle used. In the USAF configuration the manoeuvring and cargo module was cylindrical and 180 inches in diameter, for mating to the planned Titan 3G launch vehicle. A truncated version with less than a tenth of the payload could be used with the MOL Titan 3M booster. For NASA use the module was conical, flaring to 260 inch (6.61 m) diameter for mating to the S-IVB upper stage of a Saturn INT-20 or Solid motor/S-IVB launch vehicle.
It was possible to transfer crew and cargo from Big-G to the space station without extra-vehicular activity. A pressurised tunnel led from the passenger compartment to the cargo area, and another tunnel to the docking probe.
Big G used the "packaged return capability" of the Gemini-B. This included "sealed-until-needed" oxygen supply, RCS system, and retrograde and separation motors. These features, compared to Apollo, improved crew safety by assuring the spacecraft could endure extended in-orbit quiescent storage while docked to the space station.
As another alternative (obviously not favoured by McDonnell Douglas) the Big G re-entry capsule could be used with an Apollo Service Module and the Apollo Applications Program Multi-Mission Module (a palletised cargo carrier mounted, like the Lunar Module, behind the SM, with which Big G would have to dock and extract from the spent booster).

Total mass of the Big G would depend on the launch vehicle. The Titan 3M version would total 15,600 kg, delivering 9 crew and 2,500 kg of supplies to MOL in a 480 km, 50 degree inclination orbit. The NASA INT-20 version weighed 47,300 kg and could deliver 9 crew and 27,300 kg of payload to the same orbit. The Titan 3G configuration would have an orbital insertion mass of 59,000 kg in a 28.5 degree, 150 x 220 km orbit.

Crew Size: 9. Length: 11.50 m. Maximum Diameter: 4.27 m. Habitable Volume: 18.70 m3. Mass: 15,590 kg. Payload: 2,500 kg.

This is well within the specs of the larger EELV, and would deliver 9 people to ISS. Think about that. Wouldn't this be great to deliver people to a Bigelow hotel?

RobertDyck · 2004-07-31 21:02:16

A few points to consider for a lunar mission:
- heat shield, parachute, and either a floatation system or rocket assist landing are only required for return to Earth. Why bring them to the Moon?
- landing legs are only required for lunar landing, why bring them from Earth to the Moon?
- lunar ISPP: make fuel for return to Earth from lunar resources. Make metal/LOX fuel from regolith, either aluminium or magnesium.

Michael Duke suggested a reusable lunar system would leave the landing legs in lunar orbit. An Earth orbit to lunar orbit transfer vehicle would rendezvous with the legs and attach them for descent. Refuel with native made propellant then lift off to lunar orbit. Leave the legs in lunar orbit for the next mission before returning to Earth orbit. I would add a modest heat shield for Earth aerocapture left in lunar orbit. When the vehicle ascends to lunar orbit to store the legs, it would pick up the heat shield for return to Earth. I think his plan had a fuel depot at L1, filled with lunar extracted fuel. I would bypass L1 and transfer directly from lunar orbit to Earth orbit. A reusable OSP could transfer them from Earth orbit to the surface.

This plan emphasizes reusable equipment and space resources. Once the vehicles are in space, the only expendable is the EELV to lift the OSP to Earth orbit. If you don't have a reusable OSP, then it would be useless to make the lunar orbit to Earth orbit transfer vehicle reusable. Without OSP, the most reusable scenario is a reusable lunar module to ferry crew between lunar orbit and the surface. CEV would be like the Apollo command and service module (CSM), but hopefully smaller and modular. You could use a Soyuz-like ship with a separate Trans-Lunar Injection stage. The GE proposal for Apollo was the http://www.astronautix.com/craft/apollod2.htm]Apollo D-2, also a modular rather than integrated design.

There are a couple problems with Gemini for a lunar mission: you can't transfer between spacecraft without a space walk, and astronauts can't get out of their seat. It's compact design is very light, and driving a 2-seat sports car is fine for a few hours, but a bit cramped for a 3 day trip to the Moon. Big Gemini has room for 6 crew, but no transfer tunnel between crew and passenger compartment, and no docking port.

SpaceNut · 2004-08-02 11:24:42

RobertDyck:
I like the thought process for why bring things not needed for a lunar landing.
Also to develop ships that use lunar fuel resources rather than Fuels that are only available from Earth is I feel down the right path as well.
I also think we should explore the use of the Space elevator and the magnetic rail guns launch systems for Lunar use as well.

BWhite · 2004-08-02 12:30:34

Russia has a spare ISS-Zarya. Add a Bigelow Transhab or 2 and more docking ports and deploy in lunar orbit.

A week at ISS then a week in lunar orbit. How about that for a vacation?

SpaceNut · 2004-08-02 13:36:24

I like how all of you are thinking out of the Box but how can we get Nasa to implement such ideas.

The nations space programs right now can not purchase anything of the kind from Russia regardless of the price.

How can we get the private industry to go for such concepts?

Could we buy from our European friends the Automated Transfer Vehicle or do we have that same issue as before?

RobertDyck · 2004-08-02 17:24:21

Mike Duke talked about lunar ice for LH2/LOX propellant. However, space telescopes would have to be located at the equator. Descending from lunar orbit is easier to the lunar equator than the pole. We've had discussions before about quantity of lunar ice.

An alternative is aluminum/LOX. John Wickman has demonstrated http://www.space-rockets.com/lsp.html]Lunar Soil Propellant. Magnesium/LOX could also be used. He developed a magnesium/CO2 jet engine for Mars, but used nitrogen gas to blow magnesium powder in to the combustion chamber. The Moon has no nitrogen. Aluminum/LOX monopropellant was developed that was a gell of aluminum powder in LOX. You can't do that with magnesium since magnesium/LOX is shock sensitive; it will explode. For safety I'ld prefer a bipropellant for a manned craft. We need to develop a means to feed metal powder into a combustion chamber without use of nitrogen gas.

Silane was mentioned elsewhere on this board, however that's SiH4. If you have enough hydrogen for a silicon-hydrogen compound, then just use LH2/LOX. The purpose for alternative fuels is to avoid something that isn't available at the lunar equator.

I don't think we need any sort of station in lunar orbit. Just leave the legs floating free in lunar orbit until the spacecraft arrives, then drop off the heat shield for aerocapture when picking up the legs. After return orbit from lunar surface, drop off the legs and pick up the heat shield.

The heat shield doesn't have to be enough for atmospheric entry, just enough for aerocapture. To be reusable and storable for years in orbit it would have to be very durable. That means black tiles used on the Shuttle, High-temperature Reusable Surface Insulation (HRSI), are not applicable. The white tiles (LSRI) are just as fragile but have been replaced with Advanced Flexible Reusable Surface Insulation (AFRSI). AFRSI is a quilt of fibreglass fabric filled with silica fibre batting. The outer fabric is woven silica fibre but the inner fabric is woven glass fibre. An outer coating of ceramic collodial silica with silica fibres provides endurance. It's lighter and less expensive than white tiles while handling the same temperature. For a lunar mission, the reusable heat shield used for aerocapture can be woven silica held in a frame. Since a frame would hold the fabric away from the spacecraft, it wouldn't need any batting.

Ok, start argument here regarding size of the station-keeping satellite needed to maintain attitude of the landing legs or heat shield while one or the other is in lunar orbit. Attitude must be maintained during docking, and a beacon to find it. On-orbit refuellable with lunar produced fuel.

Life support: Bottled oxygen with consumable LiOH canisters to remove CO2 are all you need for the lunar transfer vehicle. A lunar base will need a recycling life support system. The lunar habitat can demonstrate the LSS for a Mars mission. I would recommend the reverse fuel cell oxygen generator, Sabatier reactor, and incinerating toilet. By the way, MDRS currently uses an incinerating toilet although there is no attempt to recycle moisture. Something you can pull the handle and forget is a lot easier than trying to maintain a grey water biological sewage processing system that feeds a greenhouse. Simnauts at MDRS kept "flushing" foreign matter that clogged the grey water system. Then you have to carefully balance the ecology of the CELSS. I would recommend forgetting about a greenhouse on the Moon, at least until a colony is established. For one thing, gardening in the greenhouse takes too much time. For another thing, a greenhouse on Mars is far more practical because you have ice, CO2, nitrogen, and soil nutrients like potassium. A closed LSS developed for ISS would be applicable for a lunar habitat.

comstar03 · 2004-08-02 18:03:58

I am disappointed in many of the comments on this topic, have any of you, sci-fi fans, If so, then you should look at the sixties - to - nineties of sci-fi, there are many good quality examples of the process we should employ for the earth and moon transfer and moonbase.

Third different issues occur in the earth - moon system they are 1. launch from earth and re-entry 2. earth transfer to moon and return and 3. moon orbit to base and return to orbit.

The main transfer and return that people are talking about is the earth orbit - moon orbit - moonbase and return. All this can be achieved by one vehicle. but remember that the vehicle must be modular and can help on the moon for construction of large components of the base.

Also you the modular design for earth orbit transfer vehicles and other vehicles including space station or planetary crafts. Limit cost use the same templates to manufacture, The Russians built and launched more vehicles into orbit on the space hardware at a lower cost base and budget.

This not a race as such but an expansion of humanity into space permanently.

:bars2:

RobertDyck · 2004-08-02 18:31:53

Hi comstar03. I'm not sure what you're complaining about. I suggested a single reusable vehicle for Earth orbit - Lunar orbit - Lunar base and return. I also suggested a reusable space taxi to carry astronauts to Earth orbit. What I didn't say is that if Earth orbit is your rendezvous location, you might as well do it at ISS. Then Earth surface to Earth orbit and return vehicle is the same one used for the space station. This sounds like the same thing you are saying.

I could emphasize that the space taxi could be a 4-crew lifting body based on X-38 or HL-20 and launched from Altas V 401. Development budget should be 1.2 - 2.0 billion. Considering both X-38 and HL-20 had been developed to the full-size mock-up stage, it should be possible to complete development including man-rating the launch vehicle for $2.0 billion. However, I've said that so many times that I expect people are tired of hearing it. Contractors asked $11-$13 billion for OSP and they usually overrun their budget; Robert Zubrin expected it would end costing $17 billion. The trick to developing a reusable space taxi is controlling contractor costs.

As Robert Zubrin said, the lunar base could be a Mars Hab with landing rockets instead of Mars heat shield and parachute.

I don't think the lunar transfer vehicle can be at all like the Earth Return Vehicle used for a Mars mission. Return from the Moon will use lunar fuel and take 3 days, while return from Mars will use Mars fuel (probably methane/LOX) and take 6 months. Life support for 3 days is quite different than 6 months. Astronaut health will require either artifical gravity (rotation) or zero-G excercise equipment for a 6 month return. The Mars Hab that Robert Zubrin designed is as big as an RV, Apollo was as big as a mini-van, Gemini was as big as a 2-seat sports car. Different requirements for different mission durations. Soyuz or Apollo D-2 could make it back from the Moon, but not Mars.

But again, other than the Mars mission ERV, I don't see the difference between what you or I are saying.

SpaceNut · 2004-08-03 05:59:21

I agree with both RobertDyck in that the use of insitu fuels is a must to lower the exploration costs.

comstar03 also makes a lot of sense in that we can learn alot from those old shows such like space 1999 and others.

Nitrogen is an inert gas, are there any other inert gases that could be found in the Lunar soil? Could nitrogen or some other inert gas also be cheaper to transport from earth to any lunar operations for use.

If it did not take so long for a journey to Jupiter or Saturn, you might be able to siphon off some of there atmosphere for use else where.
How about catching comets or searching for other forms of icy bodies?

I know, I'm a little out there.... open thinking some times can go a long way to solving problems...

GCNRevenger · 2004-08-03 08:45:01

The idea of an orbital transfer vehicle is a pretty good one in the long run, when/if regular flights to the Moon become the norm, but that is a ways down the road... The trouble of making seperable/dockable/etc "landing module," which somehow needs to be refueled, and the additional risk of unmating any Earth return hardware makes this scheme for early/near-term Lunar missions less practical than simply building a bigger rocket or assembling on orbit with entirely expendable hardware and fuel soley from Earth. Its going to be a while before a Lunar fuel factory able to convert, seperate, and store aluminum oxide or electrolyzed water fuel.

And by this time, the CEV will have matured and become routinely available, so there would be no need to make a redundant HL-20 style vehicle... The OSP concept is a dead duck entirely, CEV will take us to the Moon and be used for ISS duty (perhaps) and will cost less to use it than to develop and use a baby HL-20, which may very well cost a great deal more than the 1990's figure of $2Bn (closer to $3Bn in todays money).

clark · 2004-08-03 08:50:04

CEV will probably do 1-2 flights a year to the moon.

RobertDyck · 2004-08-03 09:27:43

there would be no need to make a redundant HL-20 style vehicle... a baby HL-20...may very well cost a great deal more than the 1990's figure of $2Bn (closer to $3Bn in todays money).

I would call a baby HL-20 redundant. In the lunar mission plan I described; the transfer vehicle is the Lunar Module. If you build an Apollo or Apollo D-2 style CSM, you'll still need a lunar module. The baby HL-20 would replace an expendable CEV, the transfer vehicle would replace the LM. Same number of vehicles but its reusable and as a side benefit gives you a reusable space taxi to ISS.

If baby HL-20 costs $3 billion, that's still a lot better than the $11-$17 billion price that Boeing and Lockheed Martin were asking for OSP.

If we never get a heavy lift launch vehicle such as Shuttle-C, then we'll need to assemble the Mars vehicle in orbit. If we have to send small pieces on Delta IV Large or Atlas V 551, we'll need an on-orbit construction shack like ISS. We already have ISS so let's use it. A reusable space taxi would make construction trips to ISS affordable. I’m thinking head here: to get to Mars we either need an HLLV or inexpensive frequent access to LEO. I’m trying to leverage the Moon thing to get us to Mars.

SpaceNut · 2004-08-03 09:39:29

With only one or two flights a year there will be very little infrastucture building no automation of build or supply and very little will change with regards to space flight being of less cost than it is at this time. Space will still remain out of reach for the average space explorer.
There must be more flights to drive pricing down....

RobertDyck · 2004-08-03 12:01:46

http://www.projectconstellation.us/arti … b=sec]This is Boeing's idea of a manned Mars vehicle. I uses modular components assembled in Earth orbit and launched with Delta IV Large. Do you know how many launches this would take? The Crew Control Module (capsule equivalent to Apollo Command Module) and Resource Module (equivalent to Apollo Service Module) would take one launch. The robotic cargo vehicle (docked to the capsule) would take another. The inflatable habitat would take another. Main engines would take another, and the fuel tank immediatly above the engines yet another. Each of the 12 fuel tanks attached to the truss would take another. I think the truss iteself would require a separate launch. That adds up to 18 launches of the largest EELV available. At $170 million in 1999 dollars that adds up to $3.06 billion plus inflation, plus man-rating, plus mission operations. That doesn't include cost of the Mars vehicle components.

Note this doesn't include any sort of lander.

So, we have 2 choices: develop a HLLV or dramatically increase launch rate for on-orbit assembly. Critics of ISS on-orbit assembly can start here. However, if congress does go with on-orbit assembly of a Mars craft, it will dramatically increase launch rate of CEV to LEO.

clark · 2004-08-03 12:10:58

Design the L1 station for eventual conversion to a manned Mars-bound ship.

Take the ISS. It's stuck there because it was never intended to be anything other than what it is- a LEO station.

Now, why do we have to hang onto that mindset?

We are going to the Moon to prepare for Mars, right?

Why not build up the infrastructure in L1 with the idea that it will eventually be used to go to Mars. Start with that intent.

If we go to the Moon slowly, we can send up elements of what we will need for Mars over the course of the entire program (think of it as a two for one deal).

by the time we finish building something that will take us to Mars, we will have learned what we needed on the Moon- convergence.

GCNRevenger · 2004-08-03 12:12:34

Who says the CEV cannot be partialy reuseable? There is the simple fact that with a limited flight rate for missions to the ISS, that the reuseability of an HL-20 derivitive will not save much if any money compared to its development cost versus simply flying additional CEV-lite to the station. Two or three flights every year for about a decade, a nice round figure for a sane remaining ISS life estimate after core complete, with a savings of $100M a flight over the cost of CEV will not even break even for the development costs... and not even that if the optimistic $3Bn pricetag can't be achieved.

Using the ISS in any shape form or fasion as an orbital launch pad is a bad idea. Lunar ships won't be assembled in orbit, they will simply be docked Russian style. No space station, no spacewalks, no nothing... docking clamps, wiring, maybe a fuel line. It really is easier and cheaper, especially given the payload penalty and lack of assembly structure on ISS.

Using the Moon as a take-off point for Mars sounds good on paper, but really, it will be simpler and easier to just bring the fuel up from Earth than it would be to manufacture it on the Moon with a Lunar fuel factory.. Especially with a heavy ion tug.. A billion dollars will buy you hundred(s) tonne masses to LEO, it just doesn't make a whole lot of sense unless numerous flights are required, particularly if the EELV line could be extended or SDV created that could reduce that 18+ launch figure down pretty fast.

The current NASA plan shaping up looks to launch an Apollo CSM style vehicle and the Lunar lander on two shots of EELV/EELV+, launch their cryogenic TLI stages one each, and send both to Lunar orbit where they dock. The CEV stays in orbit while the crew (or payload) go down in the lander, "do the Moon," and come back up to the CEV with its TEI stage.

RobertDyck · 2004-08-03 13:25:04

The concept gallary says the TLI stage consists of 2 Delta IV upper stages. Assuming it's the Delta 4-2 used for Delta IV Medium and not Delta 4H-2 of Delta IV Large, each stage with full fuel tanks will mass 24,170kg. Delta IV Large can only lift one of those into orbit at a time. Delta 4H-2 masses 30,710kg with a full tank so Delta IV Large couldn't even lift one of them. That would require 3 launches for the CSM and 3 launches for the lunar module; total 6 launches of Delta IV Large for a single Moon mission. That includes an inflatable habitat for an initial lunar surface base. What do they intend for the lunar ascent vehicle?

SpaceNut · 2004-08-03 13:33:55

Here is concept art for the lander from Boeing

http://www.projectconstellation.us/article....alb=sec

Inflatable habitat for an initial lunar surface base, using a derivative Resource Module to land on the lunar surface and providing power and cooling to the Crew.

GCNRevenger · 2004-08-03 13:41:33

Six launches isn't that bad, and it could be whittled down to four with an EELV+ arrangement. Launch the TLI engine with LOX only, then send up the CEV or Lunar lander with the LH2... as for the acent system, the little drawings i've seen don't have much, and would probobly be a tiny little capsule or even an unpressurized "rocket sled."

RobertDyck · 2004-08-03 14:47:19

I for one would want lunar ascent worked out BEFORE going to the Moon.

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