The Case for a Small CEV

John Creighton · 2006-04-06 22:31:21

CLV Cost Escalation
http://www.nasawatch.com/archives/2006/ … scala.html
Editor's note: According to reliable sources NASA's initial internal estimate of what it would cost to modify the current SRB used for Shuttle missions to serve as the first stage of the new Crew Launch Vehicle had been around $1 billion. That estimate has been revised up to around $3 billion.

It sounds like a big rise but it costs a billion to fly the shuttle so maybe it is not so bad.

cIclops · 2006-04-07 04:02:45

CLV Cost Escalation
http://www.nasawatch.com/archives/2006/ … scala.html
Editor's note: According to reliable sources NASA's initial internal estimate of what it would cost to modify the current SRB used for Shuttle missions to serve as the first stage of the new Crew Launch Vehicle had been around $1 billion. That estimate has been revised up to around $3 billion.

If this is true, it is very bad news for ESAS. The 5 segment SRB first stage was considered the least risky part of CLV development. So if the estimates for this component were out by a factor of 300% the upper stage and CEV costs must all be in doubt now. Not to mention the far more risky HLV development

EuroLauncher · 2006-04-07 06:03:29

CLV Cost Escalation
http://www.nasawatch.com/archives/2006/ … scala.html
Editor's note: According to reliable sources NASA's initial internal estimate of what it would cost to modify the current SRB used for Shuttle missions to serve as the first stage of the new Crew Launch Vehicle had been around $1 billion. That estimate has been revised up to around $3 billion.
If this is true, it is very bad news for ESAS. The 5 segment SRB first stage was considered the least risky part of CLV development. So if the estimates for this component were out by a factor of 300% the upper stage and CEV costs must all be in doubt now. Not to mention the far more risky HLV development

ESAS plans are starting to vanish, 4 Seg-SRB is replaced by a 5 Segment SRB-CLV, the large sized CEV is dumped, Methane engines are gone...so what will go next ?

GCNRevenger · 2006-04-07 06:14:10

Now wait just a minute here...

This is NASA-Watch we're talking about here, which carries a disclaimer at the top of their page that states that they aren't an offical NASA entity of any sort.

NASA-Watch is also notorious for being pretty much, well, anti-NASA. Theres no nice way to say that, I think they are anti-NASA. So many space websites, including the wonderful Astronautix, are run by people who think "their" plan is the only intelligent one, and NASA is being "stupid."

And just who is this "reliable source?" A disgruntled space science engineer whos work might be intereferd with now that exploration, not science, is the number one goal? Just a pal of the NASA-Watch staff who likewise hates ESAS since it isn't elegant and cheap?

It cost on the order of $3Bn to develop the Delta or Atlas EELV, and that was basically for a new rocket from scratch, except for Lockheed recycling engines from Atlas-III and Titan-IV. Frankly, $1Bn is probably fairly generous for five-segment SRB.

About the only realistic way that it could cost this much is if large portions of the Shuttle Army were "assigned" to the project since NASA can't lay off anybody or else basically a huge, intentional, and obvious price gouge by ATK. Neither one makes much sense, the Shuttle Army is still needed to fly Shuttle at the moment, and if ATK fails to deliver relativly on budget, they will be put out of the NASA business.

About the only senario that is plausable is that ATK thinks that the future of VSE is in doubt, and they want their $2Bn up front now instead of risking a few billion later.

GCNRevenger · 2006-04-07 06:17:46

If this is true, it is very bad news for ESAS. The 5 segment SRB first stage was considered the least risky part of CLV development. So if the estimates for this component were out by a factor of 300% the upper stage and CEV costs must all be in doubt now. Not to mention the far more risky HLV development

ESAS plans are starting to vanish, 4 Seg-SRB is replaced by a 5 Segment SRB-CLV, the large sized CEV is dumped, Methane engines are gone...so what will go next ?

The "large size CEV" was really probobly too big. The old 3m Apollo capsule could seat five in a pinch, a 5m one should seat four just fine. For the Mars return vehicle, the six crew won't be spending much time in the CEV. We're only talking twenty inches here too.

Again, the methane engine was always a "luxury" item, it was not a "compromise" to postpone it, but rather simply deselecting a bell/whistle that was on the CEV wish-list.

SpaceNut · 2006-04-17 20:07:35

Again, the methane engine was always a "luxury" item, it was not a "compromise" to postpone it, but rather simply deselecting a bell/whistle that was on the CEV wish-list.

I would appear that we are only getting half the story from Nasa these days...

NASA, Industry and Air Force Team Achieves Critical Milestone in Liquid Oxygen-Liquid Methane Engine Development Program

NASA, industry and the U.S. Air Force have achieved a major milestone in the development of next-generation spaceflight technologies, successfully completing a 103-second hot-fire test of an engine fueled by liquid oxygen and liquid methane.
The collaboration's focus has been the development and testing of a pressure-fed type of LOX-methane engine -- meaning the engine has pressurized propellant tanks with a separate gas supply to force fuel into the combustion chamber. Using this configuration, engineers developed engine start and shutdown sequences and evaluated LOX-methane engine performance over a range of fuel-mixture ratios and chamber pressures. Producing a vacuum-rated thrust of 20,000 pounds
Testing to date has demonstrated stable combustion over a range of propellant mixture ratios, engine throttle capability between 60 percent and 100 percent of rated thrust, and engine efficiencies consistent with the performance needs of future exploration missions.

This is good news...

GCNRevenger · 2006-04-17 20:35:42

Ah. So thats why NASA dropped development on it... the USAF already had one?

I wonder how far it is from a workable manned engine

Edit: Hmmmm questions, questions...

-Griffin obviously knew about this program, so what gives?

Maybe he only canceld NASA funding, since the USAF was going to proceed with NASA help or not, saving money?

Maybe the engine is a long ways off from use? (this seems most probable)

SpaceNut · 2006-04-18 20:05:03

I agree lots of questions, such as how much longer would the engine burn time need to be for a lunar lander..
Seems that they have gotten quite far with the ability to throttle the engines preformance thou.
As far as saving money by cancelling Nasa funding why not get the military to fund when you can...

publiusr · 2006-04-28 14:00:20

I am very glad that the Air Force is actually helping the cause of spaceflight for once.

I guess things are better now that Jumper is gone.

SpaceNut · 2006-05-08 21:01:14

Now for the other shoe.. ATK Selected for Technology Development of Non-Toxic Liquid Oxygen-Liquid Methane Engine for NASA

New Engine Could Be Used as the Crew Exploration Vehicle's Future Propulsion System. Alliant Techsystems has received a $10.4M technology development contract to reduce the risk to develop a non-toxic Liquid Oxygen (LOx)-Liquid Methane rocket engine that could be used on future Crew Exploration Vehicles (CEV).

Great but why is Nasa doing this is the Air force is also...

Why can Nasa not stick to its guns whenthey have made a choice already?

NASA's Exploration System Architecture Studies have identified a non-toxic LOx-Methane propulsion system as a preferred candidate for future CEV architecture because it eliminates the need for special ground handling procedures associated with traditional nitrogen tetroxide and monomethyl hydrazine propulsion systems. Non-toxic engines may significantly reduce the cost of fueling and servicing operations.

SpaceNut · 2006-05-09 21:11:44

Here is the twist to the ATK..
XCOR Aerospace Teams with ATK on Methane Rocket Engine for CEV; Developing Nontoxic Propulsion Alternatives for NASA

Together with ATK, XCOR will develop the initial workhorse version of a 7,500 lbf LOX/methane engine for NASA’s Crew Exploration Vehicle (CEV).
Relevant to CEV engine development is the XR4K5 engine and the 3M9 LOX/methane engine.
XCOR has designed, built, and tested several different rocket engines, including a 50 lbf LOX/methane engine and an 1,800 lbf LOX/hydrocarbon engine which are highly relevant to this program. Under DARPA sponsorship, XCOR also designed a 10,000 lbf LOX/methane engine which will form the basis for the design of the NASA CEV LOX/methane engine.

So how powerful does the engine for the CEV need to be and is this also for the LSAM ascent stage planning for when we get the insitu manufacturing of methane at the base going...

GCNRevenger · 2006-05-10 05:22:24

Oh no, X-Cor building major components for the ESAS plan??? We're doomed.

SpaceNut · 2006-05-12 07:09:33

Reposting to keep developement work that is ongoing in the CEV threads.

So back to the topic at hand of "Do you (exactly) know how to "man-rate" a rocket?" well if this news release is of interest as the title goes it is all in the testing.
NASA Ames Tests Heat Shield Samples for Spaceship Capsule
Initial tests of materials that could be used in the heat shield for the new spaceship, the Crew Exploration Vehicle (CEV), were recently completed at NASA Ames Research Center in California's Silicon Valley.
News media are invited to Ames' arc jet facility, Bldg. N234, on Thursday, May 18, from 10 a.m. - 2 p.m. PDT to see small heat shield samples that engineers tested in an apparatus that NASA engineers describe as a 'room-size blowtorch.'
The initial testing at Ames is part of the advanced development activity needed to create a heat shield for the CEV crew capsule. At 10:30 a.m. PDT, there also will be short presentation in the arc jet facility, where the tests were conducted.
NASA is working to create and test the 16.5-foot (5-meter) diameter, Frisbee-shaped heat shield that will be attached to the base of the cone-shaped CEV crew capsule. The shield must protect the capsule and its astronaut crew from the searing heat that develops during flight through the atmosphere when returning from either low-Earth orbit, or from the moon.

RedStreak · 2006-05-12 15:21:53

Rush? Now there is an understatement of biblical proportion...
Bob's direct moon flight plan is a pretty BAD idea if you wanted to actually DO anything on the Moon. Notice how the big HLLV rocket is only able to deliver the CEV capsule to the surface with just enough fuel to get home again, which means that you get basically zero payload on your Moon landing.

The Crew Vehicle is only meant to deliver the crew, and the crew habitat. Its NOT a cargo-loading shuttlecraft.

Any heavy cargo can be launched by itself without the CEV involved at all. Look into NASA's "Vision" - the CEV all-in-all is "optional." All it does is play piggy-back to the Lunar Lander and EDS (Earth-Departure-Stage). You don't even need minor tweaking to the HLV-half of the architecture to delive some BIG modules to the lunar surface like an oxygen refinery or the Hubble-equivelant of a Lunar Telescope.

Zubrin's plan favors simplicity, NASA's flexibility. Either way works fine for crew delivery. Personally my concern is just getting something useful on the ground: telescopes, construction materials, base materials...anything that works to establish a sustainable facility.

GCNRevenger · 2006-05-12 17:23:22

No.

Although we will eventually build a base on the Moon probably, this base site won't be the only place we will be landing. Because of this, whichever Lunar arcitecture is used, the manned lander must have non-trivial payload capacity. Period. End quote. Full stop.

Being that this is non-negotiable, then Bob's plan simply won't do. His figures make it sound less-bad once we have a LOX supply on the surface, but we wouldn't have that at sites away from the base. Because a direct-flight mission has to lug the Earth-return fuel off the Lunar surface, it incurs a hefty payload penalty, which means that direct flight simply can't.

The two plans are qualitatively different, the ESAS plan permits nontrivial surface payload to ride with the crew on the LSAM, Bob's plan doesn't. They are not comperable, it is not a matter of "flexibility versus simplicity," it is a matter that Bob's plan is simply bad for doing what should be done.

Also, Bob's version of the CEV is a cramped three-seater, maybe shoe-horning in a fourth for short durations, but considerably smaller then the present ESAS 5m CEV. This is not nessesarry nor acceptable.

The only way to "fix" this would be to enlarge the CaLV into the 150-160MT lift region, which probably isn't going to happen. Even bolting on a quartet of five-segment SRBs, adding a 6th RS-68 to the first stage, and adding a second J-2X to the upper stage might not hit that mark.

publiusr · 2006-05-19 11:17:33

That is why I keep hoping for a Saudi Sea Dragon or Nexxus class vehicle.

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#76 2006-04-06 22:31:21

Re: The Case for a Small CEV

#77 2006-04-07 04:02:45

Re: The Case for a Small CEV

#78 2006-04-07 06:03:29

Re: The Case for a Small CEV

#79 2006-04-07 06:14:10

Re: The Case for a Small CEV

#80 2006-04-07 06:17:46

Re: The Case for a Small CEV

#81 2006-04-17 20:07:35

Re: The Case for a Small CEV

#82 2006-04-17 20:35:42

Re: The Case for a Small CEV

#83 2006-04-18 20:05:03

Re: The Case for a Small CEV

#84 2006-04-28 14:00:20

Re: The Case for a Small CEV

#85 2006-05-08 21:01:14

Re: The Case for a Small CEV

#86 2006-05-09 21:11:44

Re: The Case for a Small CEV

#87 2006-05-10 05:22:24

Re: The Case for a Small CEV

#88 2006-05-12 07:09:33

Re: The Case for a Small CEV

#89 2006-05-12 15:21:53

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#90 2006-05-12 17:23:22

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#91 2006-05-19 11:17:33

Re: The Case for a Small CEV

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