Post central for information on CEV III - Continued from previous

Martin_Tristar · 2005-02-21 01:30:44

The issue is FULL FUNDING OF SPACE EXPLORATION!!!!!

The US Political Structures have always limited the funding of NASA and other related space activities. We have many serious issues to overcome to launch / land and return a manned mission to the moon and mars, and continue manned missions until the permanent outpost or settlement structures are in place for long term placement of staff in orbit, on the moon and travelling exploring our solar system.

IT's a JOKE Funding from congress , it should be twice or three times the current budget. !!!!!!!!!!! Let us out to explore >>>>>

:bars2:

SpaceNut · 2005-02-21 06:55:04

TRIAL BY FIRE is an Aviation Week & Space Technology article about the Boeing Delta IV Heavy launcher as a possible options for NASA Crew Exploration Vehicle (CEV).

Boeing says even modest upgrades could double the Delta Heavy's Earth orbit capability to more than 50 metric tons, including being able to fire up to 20 metric tons on escape trajectories to Mars.
The IV Heavy is also competing against shuttle-derived or still proprietary commercial concepts, including options that might use the Delta IV's RS-68 engines

The formal CEV request for proposals NASA is to issue in early March will call for a four-person CEV launch mass no greater than 20 metric tons (44,000 lb.). In comparison, the earlier three-person Apollo Command/Service module needed for Earth orbit and lunar missions had a launch weight of about 67,000 lb. topped by an 8,000-lb. launch escape tower, 34 metric tons total.
Any medium launcher options for CEV would, however, have to be equipped with more solid rocket boosters than have been flight tested on either the new Atlas or Delta vehicles. For example, the Atlas V 551/552 medium vehicle with five solids and the Delta IV Medium with six would be needed to satisfy the minimum performance required to launch the 20-metric-ton CEV.

Let the battle comence as to who has the better rocket, actually if it comes down to it it may be who is cheaper that may win IMO.

The Atlas V Heavy would look similar to the Delta IV Heavy, but instead use Energomash/Pratt & Whitney RD-180 oxygen/kerosene engines. The Russian engines are now assembled near Moscow, but are slated for coproduction at Pratt's West Palm Beach, Fla., facility by about 2007. Like the RS-68s, the 860,000-lb.-thrust RD-180s have a 100% safety record.

clark · 2005-02-21 09:02:01

Bill, you need to do better than quotes from bleeting SpacePolitics!

To support the VSE, a reactor design compatible with lunar/martian surface operations is a different beast than a deep space NEP reactor due to material issues.

What was said here? That the requirements for lunar/martian surface operations are different that the requirements for propulsion. [smack forhead] Of course! We are suffering from the case of the obvious, aren't we?

So let me ask the practical and rationale among the group, what makes more sense: Developing nuclear propulsion cabaility to get to where we want to go, or developing nuclear power generation prior to being able to even get there? It's like complaining about a car being built not having the tires on before you even put the engine in.

Can we provide power on the Moon/Mars using augmented NEP designs? Isotope generation has been used on probes, and we always have the option of solar for minimial power generation. First step is to develop the means and experience in nuclear power generation in space. We can then take that research base and apply it to use as power generation on specific locales.

Both concepts are completely out of the realm of experience of DOE-NR which deals with water reactors. It will take them several years just to get comfortable with the materials issues let alone optimizing the design for space applications.

This is total hog-wash. DOE-NR was put in charge because they have years of process experience in maintaing nuclear systems. It's their damn saftey record that got them the gig. This statement also fails to realize that DOE-NR is teaming up with NASA counterpart. DOE-NR is part of a team that brings tools and skills and experience that are not fully realized inside NASA. No one has built space reactors, so no one is fully qualified to build the things alone. WHich is why NASA is brining it's own tools and skills and experience to the table for the project.

As for the time line... several years? So freaking what?! We won't need a space based nuclear reactor until 2020. 15 years dude. You know, when we are ready to move beyond the Moon!

Prometheus per se is being rolled into another project since we may not have the HLLV needed to fly JIMO and I do not believe there is any funding in the VSE - - whatsoever - - for reactors that can generate surface power (the MarsDirect reactor) or provide propulsion other than nuclear ion.

Prometheus is pursuing two different track for nuclear propulsion and power generation. JIMO was supposed to be the testing system for the propulsion system. Even if JIMO is cancelled, something else will be used for a demonstration.

I do not know, but it would seem easy enough to poll grad students at MIT or CalTech. If Prometheus is to be the tip of a very big push in the space-rated reactor field, then graduate advisors should know that already. If not, then who will build those reactors?

Graduate advisors "know" by their ability to secure government grants by which to pay graduate students. Those grants have been increasing as a result of VSE. No one get's told what the future holds unless they have a one eyed hobo and ride a box train.

According to a Congressional source, NASA is planning to transfer $150 million in FY05 funding out of Project Prometheus to other, unidentified programs.

Followed by:

NASA hasn't yet determined what the pilot mission of its nuclear power and propulsion initiative will be, as agency officials testified before the House Science Committee last week, taking some of the pressure (and, hence, need for funding) off of the program. However, some in Congress reportedly plan to press NASA to maintain its commitment to Prometheus, including perhaps restoring JIMO in the FY06 budget proposal

What are you complaining about Bill?

GCNRevenger · 2005-02-21 12:49:49

Two things SpaceNut:

1: The old Apollo service module had to lug along all the fuel needed to brake into Lunar orbit with the Lunar module, and to push the CSM stack back to Earth from Lunar orbit. The basic CEV vehicle doesn't need to do this, as the lander can be sent to Lunar orbit seperatly. Also, if the TLI & TEI stages can be sent up seperatly, the basic orbital CEV doesn't need much fuel at all. Solar power versus fuel cell power too.

2: The basic Delta-IV Medium can probobly be upgraded to launch the orbital CEV with no solid rocket boosters at all. An improved version of the RS-68 with regenerative cooling, Lithium/Aluminum alloy fuel tanks, and perhaps slushed hydrogen would make the basic Delta-IV Medium just as powerful as if it had a full set of SRMs.

What Lockheed SHOULD be doing is abandon the Atlas-V design, and start work on a heavy-lift rocket. With the higher fuel density, an Atlas-style core with the same diameter and a little longer then a Delta-IV core equipped with a trio of RD-180 engines could launch ~40MT to orbit, no solid rockets at all. Equip the thing with a pair of (hopefully retired) Shuttle SRBs, and you have an HLLV in the 80MT range, perfect for lauching Lunar payloads directly... or a Mars ship in 2-3 pieces.
---
Bill:

Actually the difference in reactors between a small surface reactor and a JIMO 100/300kw class reactor are not that great in concept... All you really need to do differently is to reduce the radiator area and repackage the thing. Perhaps add a coolant loop for heating HABs/greenhouses or melting Lunar/Martian ice.

Initially I failed to see the advantage of a small gas-cooled reactor versus a liquid-metal only reactor with direct thermal conversion, but actually it makes sense if you want to build a much bigger power plant later on, since it would vastly reduce the reactor's requirements and radiation release.

Everything else, I agree with Clark's last post... you are making a mountain out of a molhill.

BWhite · 2005-02-21 14:27:12

Everything else, I agree with Clark's last post... you are making a mountain out of a molhill.

Well all-righty, then.

"Uncle"

clark · 2005-02-21 14:37:55

Well all-righty, then.
"Uncle"

I'm just glad I'm right. I can tell Bill is just waiting with a big, "I told ya so," if it goes otherwise.

I'll admit there isn't as much detail as one would like, but a lack of hard details dosen't mean there is some make-work conspiracy going on.

What is going on, if you look around, is some massive fundamental shifts in the make-up of NASA and how it does business. People have been saying NASA has grown fat over the years- well, it's getting lean in a hurry. Shuttle is being retired (albeit not as quickly as one may like, but it is being retired). The focus is shifting from aeronautical research to greater space exploration related research.

Yes, nothing gets built until later, but the programs get started, which allows entrenchment of vested interests to protect their "babies" before a new administration can undo anything. Clinton couldn't kill ISS (well, in his own way, he did, but I digress, it got built...sort of).

John Creighton · 2005-02-21 22:00:21

What Lockheed SHOULD be doing is abandon the Atlas-V design, and start work on a heavy-lift rocket. With the higher fuel density, an Atlas-style core with the same diameter and a little longer then a Delta-IV core equipped with a trio of RD-180 engines could launch ~40MT to orbit, no solid rockets at all. Equip the thing with a pair of (hopefully retired) Shuttle SRBs, and you have an HLLV in the 80MT range, perfect for lauching Lunar payloads directly... or a Mars ship in 2-3 pieces.

In the article presented by space nut Boeing did say that it had considered modifying the delta IV heavy so that it could lift 80 MT to LEO with solid rocket boosters. However, the modifications would required a modification of launch facilities and were consequently not pressured. As I said before I think the 40-80 MT range is very good weight range for NASA. Perhaps currently the 20-40 range is better suited to the commercial and military sector. However, maybe in the near future we will see many versions of the Delta for these varying weight ranges.

SpaceNut · 2005-02-22 05:46:34

NASA rushes plan to send humans to moon, Mars, despite doubts among scientists, Congress

NASA is racing to carry out President Bush's costly vision of sending humans back to the moon and then on to Mars - despite the federal budget squeeze and doubts in Congress and the scientific community about the plan's wisdom.
Even some of the project's allies are balking at its price tag and headlong pace.

It's been a little over a year since Bush announced "The President's Vision for U.S. Space Exploration," but the space agency has already awarded 118 preliminary contracts for the project. It's requesting fresh ideas from industry and universities in order to launch a large new spaceship, called the Crew Exploration Vehicle (CEV), three years from now.
The $15 billion CEV is supposed to take over from today's aging fleet of space shuttles and carry astronauts "to the moon, Mars and beyond," as NASA officials like to say.
By this summer, two aerospace teams will be chosen to construct competing prototypes of the CEV. A final version will by chosen by the end of 2006, and the first unmanned flight is scheduled for 2008.

So this said we will end up with two in compatible systems with a choice being made at the end. ???

Why not give both contractors the same design and see which one can pull it off using new components so as to limit off the shelf designing from the company that has it putting the other at a disadvantage to coming up with the same product. The increase in funding request of $3.2 billion for the second year (2006)of the Moon-Mars project is up from the first years (2005)$2.6 billion.

GCNRevenger · 2005-02-22 07:04:06

Its the same strategy as the F-35 program which worked pretty well.

NASA doens't have a design, only a vauge idea of what it wants. If you give two different design teams the same engineering sketches, requirements, basic numbers... you'd come out with two very different spacecraft anyway.

BWhite · 2005-02-22 11:55:31

http://www.menafn.com/qn_news_story.asp … xn0BgvY]Is Kistler back?

In June, the Government Accountability Office advised NASA the protest [Musk vs Kistler] was valid, so the agency rescinded its deal with Kistler -- the matter closed, but hardly forgotten.
The opening bell for Round 2 sounded this month with the release of NASA's proposed spending plan for fiscal year 2006, which begins Oct. 1, and the clock ticking down toward the space shuttle's retirement.
NASA now is far more than interested in alternative transportation services to the space station. With Russia on schedule to complete its contractual requirements for rides to the station on Soyuz spacecraft next year, NASA must secure other transportation to the station.
In addition, though the space shuttle's anticipated return to flight this year -- currently scheduled for May 15 -- should buy NASA some time, there will be at least a four-year gap between the shuttle fleet's retirement in 2010 and the start of crew transports aboard NASA's proposed follow-on spacecraft, the Crew Exploration Vehicle.
Thus, in reviving its call for "alternative access to the space station" and budgeting $160 million for such services in 2006 -- and a total of $1.7 billion over the next five years -- NASA now is adding an option for commercial companies to ferry not just cargo, but also crewmembers to space. If it comes to fruition, NASA itself will provide a huge incentive for the nascent sub-orbital commercial spaceflight industry to aim for higher ground.
Kistler, for one, is keenly interested in transporting goods and eventually people into orbit for NASA.

Does UPI have this right? $1.7 billion for "alternate access" to ISS? And the Kistler in the running?

Thus, in reviving its call for "alternative access to the space station" and budgeting $160 million for such services in 2006 -- and a total of $1.7 billion over the next five years -- NASA now is adding an option for commercial companies to ferry not just cargo, but also crewmembers to space.

= = =

More:

With the K-1 vehicle 75 percent completed and financing lined up to emerge from bankruptcy within a month or two, Kistler has a new business plan, which while not dependent on NASA, is positioning the firm to ride the waves of change that have been pummeling the space agency since the 2003 shuttle Columbia accident and President George W. Bush's redirection of the agency's priorities from the shuttle fleet and the space station to human exploration of the moon, Mars and beyond.
* * *
Still, when NASA puts out the call for commercial space transport service proposals later this year, Brinkley said the K-1 will stand on its own.
"I think we have an inherent capability," he said.
K-1's debut flight is expected in early 2007, Brinkley said, adding that the company is looking at alternative U.S. launch sites, particularly at the Cape Canaveral Air Force Station in Florida, to serve NASA and a variety of commercial customers.

Edited By BWhite on 1109095129

clark · 2005-02-22 12:04:24

Not quite...

While the aspects regarding NASA budgeting funds for alt-access is true, take what the CEO of Kistler is saying with a grain of salt.

The CEO of Kistler offers a business option, but so do many others. And many others are not struggling to get out of bankruptcy.

Ad Astra · 2005-02-22 12:29:44

Why not give both contractors the same design and see which one can pull it off using new components so as to limit off the shelf designing from the company that has it putting the other at a disadvantage to coming up with the same product.

That's the same approach NASA tried with the Space Shuttle. The concept was designed at the Manned Spaceflight Center, then the inudstry teams were asked to bring it to fruition. In the end, the result was incredibly disappointing and deeply flawed.

SpaceNut · 2005-02-28 05:39:43

The I guess the question is then why was it that "The concept designed at the Manned Spaceflight Center" vehicle win out over the "the industrial teams" if it where truly that bad.
This is also not quite the same as a fly off where two competitors are asked to provide like products.

Ad Astra · 2005-03-01 19:17:50

The Request For Proposals came out today. I think GCNRevenger will be vindicated by a detail made clear in the RFP: the Earth Departure Stage will be used for lunar orbit insertion. The delta-V requirement on the CEV will be lower, enabling the 20 tonne launch weight.

GCNRevenger · 2005-03-01 19:55:20

Its not cut & dry yet. You would probobly use such a stage if you went with EELV+ or with a light HLLV (Shuttle-C, Super-Atlas) anyway to minimize the vehicle's Lunar throw weight and maximize commonality. It also means that NASA can get started on VSE without picking a particular launch method yet.

SpaceNut · 2005-03-04 06:37:26

From the CREW EXPLORATION VEHICLE, SOL NNT05AA01J document page. I have taken a few minutes to go though some of the documents to summarize the key points to allow for more discusion.

For those that need to know the Acronym List and a glossary

Final Request for Proposal (RFP) NNT05AA01J, Crew Exploration Vehicle, Phase 1 Contract

The Nation’s Vision for Space Exploration sets a goal of developing a new Crew Exploration Vehicle by 2014 that is capable of carrying astronauts beyond low Earth orbit and a goal of landing astronauts on the Moon no later than 2020. The CEV represents one building block in a future exploration architecture that can send astronauts to the moon and form the basis for exploration missions to other destinations.
Crew Exploration Vehicle is a full and open competition. The anticipated period of performance is September, 2005 through December, 2008.

Scope of the Crew Exploration Vehicle Statement of Work

• Crew Exploration Vehicle (CEV) – The system that transports humans to Low Earth Orbit (LEO), Lunar Orbit and back to Earth.
• Crew Transportation System (CTS) – The CEV, the CEV launch vehicle, and the ground systems necessary to operate the CEV.
• Constellation – The elements of the Constellation System of Systems including the CEV Launch Vehicle, Lunar Surface Access Module, Earth Departure Stage, Ground Support System, In-Space Support System, Destination Surface Systems, and other Constellation Systems such as a common docking mechanism, common rendezvous and proximity operations sensors, the common Constellation communications architecture, flight crew equipment including provisions for EVA, and standardized human interfaces.

Statement of Objectives for the Crew Exploration Vehicle

On January 14, 2004, the President of the United States directed the National Aeronautics and Space Administration (NASA) to embark on a robust space exploration program that will advance the Nation’s scientific, security, and economic interests. To meet the goals and objectives of our new vision, NASA plans to deploy a set of systems, large and small, that will be integrated into a “system of systems”. This includes Earth-to-orbit and in-space transportation systems, systems required for human health and performance, and robotic systems that will assist humans as they travel and explore.
CEV is the first component in the system-of-systems that will be built under the NASA Constellation Program and is the subject of this request for proposals.
• Spiral 1: Earth Orbit Capability. Spiral 1 establishes the capability to test and checkout crew transportation system elements in Low Earth Orbit in preparation for future human exploration missions to the Moon. As new exploration elements necessary for future spirals are developed, they will be tested with the Spiral 1 CEV in the space environment to prepare for future exploration. The objective of crewed access to low earth orbit will be met by 2014.
• Spiral 2: Extended Lunar Exploration. Spiral 2 establishes the capability to conduct human exploration missions on the surface of the Moon for extended durations. In this context, extended duration is defined as the capability to support the crew on the surface of the Moon for a minimum of four days. This objective will be met in the 2015-2020 timeframe.
• Spiral 3: Long Duration Lunar Exploration. Spiral 3 establishes the capability to conduct routine human long duration missions on the surface of the Moon to test out technologies and operational techniques for expanding the human presence to Mars and beyond. Missions in Spiral 3 will extend in duration from those obtained in Spiral 2 up to several months to serve as an operational analog of future short stay Mars missions. This objective will be met after 2020.
A key aspect to spiral development will be to develop new technologies that improve performance and lower cost over time. This is crucial to maintaining affordability and achieving the Nation’s goals for future exploration.
The CEV is designed from the outset as a key element of the Constellation “System of Systems” meeting at minimum Spiral 2 requirements with a clear plan to meet Spiral 3 requirements. Meeting Spiral 3 from the outset is a goal.
• Spiral 1 components include the CEV, a CEV launch vehicle, and ground support systems infrastructure. The CEV and launch elements will safely transport the crew from the surface of the Earth to Low Earth Orbit and return them to the Earth’s surface at the completion of the mission. The Launch System provides the capability to launch the CEV to Low Earth Orbit. The CEV provides the necessary crew habitation functions during ascent, on-orbit, and entry, including mission aborts.
• Spiral 2 consists of the Spiral 1 elements, or derivatives of those elements, plus the Earth Departure Stage (EDS) to transport elements to the lunar vicinity as well as the Lunar Surface Access Module (LSAM) that provides the capability for the crew to access the lunar surface. The CEV provides crew habitation from launch to lunar orbit and return to the Earth surface, including aborts during Earth ascent. The CEV provides the transportation functions to return from lunar orbit to the Earth surface. The EDS provides the propulsive accelerations needed to transfer the various flight elements (CEV and LSAM) from Low Earth Orbit to lunar orbit and provides the deceleration for lunar orbit insertion. The LSAM provides the crew habitation and transportation functions from lunar orbit, to the lunar surface, and return back to lunar orbit. In addition, the LSAM provides the capability for the crew to conduct science and perform routine EVA on the surface of the Moon. Finally, the Cargo Delivery System (CDS) is used to deliver un-crewed elements to low Earth orbit and/or lunar orbit. The CDS consists of an EDS and a Cargo Launch Vehicle.
• Spiral 3 requires various additional surface elements to support the crew for the long duration missions. These surface elements have not been completely defined at this point, but will provide basic functional capabilities including habitation, communication, power, extended range mobility, enhanced science capabilities, and other functions.

For purposes of this request for proposals, industry is expected to provide an initial concept for a CEV spacecraft that shall:
1. Have a total gross liftoff weight (GLOW) of less than 20 metric tons.
2. Provide an abort capability during all phases of flight.
3. Be 2-fault tolerant to hardware component failures within safety critical systems except where design to minimum risk is approved by NASA.
4. Integrate with the Launch Vehicle (LV) to achieve low earth orbit.
5. Integrate with the Earth Departure Stage (EDS) to achieve lunar orbit.
6. Integrate with the Lunar Surface Access Module to achieve lunar surface mission objectives.
7. Integrate with Ground Support Systems for launch processing and mission control.
8. Integrate with In Space Support Systems to support overall Constellation command, control, communication, and information requirements.
9. Be capable of orbital maneuvers and rendezvous/docking with other Constellation systems.
10. Be capable of return from lunar orbit to the earth surface without assistance from external Constellation elements.
11. Be capable of supporting human life from launch on the earth surface through mission complete on earth surface during a maximum CEV crewed mission duration of 16 days.
12. Abort capability independent of LV or EDS flight control.
13. Be capable of unmanned operations for test flight purposes during Spiral 1 efforts and during lunar surface activities for Spirals 2 and 3.
14. Minimizing ground processing interfaces while maintaining redundancy separation standards and minimizing potential hazards.
15. Provide the capability to conduct missions with 1, 2, 3, and 4 crewmembers with a minimum habitable volume of 3.54 cubic meters per crew member.
Initial Performance Parameters
1. Launch weight mass trades (both increases and decreases), including taking advantage of performance gains by mass reduction during ascent
2. Ability to abort anytime during all mission phases
3. Inclusion of the LSAM functionality within the CEV system
4. CEV direct return vs. Earth Capture
5. Mission Duration (both manned and unmanned mission phases)
6. Crew size (up to 6 crew members) and crew habitable volume allocations.
7. Splitting CEV functionality into modules (e.g., earth surface to LEO, LEO to Lunar orbit, Lunar orbit to Earth return)
8. Human Rating Requirements cost drivers
9. CEV system support of spiral 3
10. CEV support for transfer of crew to and from International Space Station (ISS)
11. CEV support of Extra-Vehicular Activities (EVA) operations
12. Provisions for common Constellation System elements (eg Docking systems, Communication systems)

I note that the spirals are to use the cev for each and must have a plan for this. Sort of designing the CEV from its destination and working backwards to the starting point for a modular construction.

SpaceNut · 2005-03-18 06:43:57

Is the CEV finally taking shape as to what is needed or is it just still feeling out what can be supplied by those in the business.
Space Watch: Spacefaring by bureaucrats
Is it just a choosing to hold onto the purse strings a little to tight or is it a delaying tactic to not let Nasa get started until the ISS and shutle are through.

NASA intentionally has tried to keep its requirements for the CEV somewhat vague. The spacecraft should weigh 20 metric tons or less. It should be capable of housing from one to four astronauts for as long as 16 days. It should be able to rendezvous and dock with future lunar landers and interplanetary modules -- dubbed, respectively, the Lunar Surface Access Module and Earth Departure Stage.
The CEV also should contain systems that will allow a safe abort throughout all phases of its flight.

This sections sounds like Nasa truely wants more that one product.

Other than these general requirements, NASA has left the design entirely up to the contractors planning to offer proposals. The agency even has allowed contractors some additional flexibility in their designs.
For example, if a company thinks it can build a vehicle that can keep a crew in space longer than 16 days, or with a crew capacity as high as six, the RFP permits the additional capability. Companies also are free to incorporate -- or not -- an ability for the proposed spacecraft to dock with the International Space Station.

SpaceNut · 2005-04-06 05:15:48

Since there already was a crew exploratory vehicle thread I am posting this here as a search turned up that Northrop had been previously mentioned in the locked one.

Northrop Grumman, Boeing Announce Companies Supporting Crew Exploration Vehicle Team
While it is good to see who the players are and to what they will bring top the plate from this team. I found the following quote interesting in terms of the size of the shuttle army.

United Space Alliance - Bringing the Northrop Grumman/Boeing team extensive experience in space operations, United Space Alliance's 10,000 employees in Florida, Texas and Alabama

The next was on the flyoff:

Following a flight demonstration in 2008, the space agency is expected to select a single contractor team to begin full-scale development of the CEV.

Wouldn't you think that the demonstrator vehicle would be a complete unmanned full scale unit in the flyoff not some model concept.

SpaceNut · 2005-04-08 12:16:15

There are some that have argued not to use the SRB engines for a light CEV to LEO orbit crew transport. There arguements range from they will explode to what happens if we need to abort and can not shut down the SRB once it starts burning.

The fact that the SRB's are built in segments would mean that if we could seperate the segments at any joint that the engine would loss nozzle pressure and then this would allow for a better chance for seperation by the capsule rescue tower for any such abort sequence of events that might happen to need this feature.

GCNRevenger · 2005-04-08 18:23:59

No, if the fuel grains (segments) would seperate, then the surface area and the burn rate increase. Alot. Kaboom...

The only way to effectively shut off a solid engine is to intentionally blow off the nose cone, which will make an equal amount of thrust blow out either end... but I don't like the sound of that one little bit.

The best thing would be to eject the boosters and push the noses away from the vehicle, which would make them fly off away from the rocket... but thats not a very good option either.

The best option is simply not to carry any SRMs at all.

Mad Grad Student · 2005-04-09 22:18:20

It sounds from the RFP like NASA is going for a multi-launch EELV-class architecture for lunar missions, at least for now. The only decent option we have for this right now is to actually use EELVs; the idea of using more SRBs gives me the jitters. They don't throttle, they don't shut down, they give virtually zero warning before blowing up, and have a nasty tendancy to kick off while they're being processed; it's for the best if we can just keep solids out of the picture entirely. It will be interesting to see what Spacex can come up with as far as heavy-lift (assuming he means EELV-class by that). Maybe they'll end up bidding for the CLV; if they do that will be a big development for the private sector.

GCNRevenger · 2005-04-09 22:28:21

I dunno, I think that NASA is pretty split at the moment. With Griffin at the helm, who is staunchly pro-SDV, anything could happen.

If the CEV really does weight 20MT, its sketchy if any of the EELV's could lift it without solid rockets. Atlas could perhaps do it, but Delta probobly not.

I think that the risk is acceptable, so long as there is a good escape mechanism. As in, one capable of hair-trigger ejection if there is a serious fault detected.

Elon's rocket, the Falcon-V, is under half the size needed. You'd need a tripple-barrel version to launch CEV or something.

Mad Grad Student · 2005-04-10 13:32:59

Spacex says that they're working on an F-1 class "super Merlin" engine that will power their heavy-lift launch vehicle. By heavy-lift I'm guessing they mean Ariane 5/EELV class, the kind of rocket that can loft two commercial sattelites to GEO at once. That could be in the range for the CLV, and be an attractive alternative to Boeing and LockMart. They've also alluded to a "super heavy lift" (SDV-class?) booster that they'll consider developing "if conditions warrant." The interesting thing is that if Spacex is as serious about this as it says it is it could put an clean-sheet launch vehicle in the running for heavy-lift, without requiring SDV or advanced EELV concepts. It's something to keep an eye out for if nothing else.

Things will probably change between now and when the CEV is brought to the pad, so we could see heavy-lift come back into vogue. EELVs will probably be just fine as far as safety goes as long as a highly effective abort capability is included. However, heavy lift does make things a whole lot cleaner, simpler, and perhaps cheaper once you can get past developing the launcher. The next year or two should be pretty exciting as NASA starts to make these critical choices.

GCNRevenger · 2005-04-10 14:22:22

I think that its too easy to put too much faith in Elon... he still hasn't flown even his little dinky rocket, and he's already talking about a competitor to the large EELVs or even a Saturn-V class heavy lifter? Iiii don't think so

Grypd · 2005-04-10 15:05:24

Still Elon is at the beginning and can truly say that for him anything is possible...Of course this requires funds, a market and technology, but these problems can all be rectified

New Mars Forums

Announcement

#76 2005-02-21 01:30:44

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Re: Post central for information on CEV III - Continued from previous

#89 2005-03-01 19:17:50

Re: Post central for information on CEV III - Continued from previous

#90 2005-03-01 19:55:20

Re: Post central for information on CEV III - Continued from previous

#91 2005-03-04 06:37:26

Re: Post central for information on CEV III - Continued from previous

#92 2005-03-18 06:43:57

Re: Post central for information on CEV III - Continued from previous

#93 2005-04-06 05:15:48

Re: Post central for information on CEV III - Continued from previous

#94 2005-04-08 12:16:15

Re: Post central for information on CEV III - Continued from previous

#95 2005-04-08 18:23:59

Re: Post central for information on CEV III - Continued from previous

#96 2005-04-09 22:18:20

Re: Post central for information on CEV III - Continued from previous

#97 2005-04-09 22:28:21

Re: Post central for information on CEV III - Continued from previous

#98 2005-04-10 13:32:59

Re: Post central for information on CEV III - Continued from previous

#99 2005-04-10 14:22:22

Re: Post central for information on CEV III - Continued from previous

#100 2005-04-10 15:05:24

Re: Post central for information on CEV III - Continued from previous

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