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#1 2005-06-07 20:39:48

BWhite
Member
From: Chicago, Illinois
Registered: 2004-06-16
Posts: 2,635

Re: Breaking news? - Admiral Steidle resigns


Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]

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#2 2005-06-07 21:10:46

Commodore
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From: Upstate NY, USA
Registered: 2004-07-25
Posts: 1,021

Re: Breaking news? - Admiral Steidle resigns

http://www.nasawatch.com/archives/2005/ … ore]Sounds like the poops about to hit the fan


"Yes, I was going to give this astronaut selection my best shot, I was determined when the NASA proctologist looked up my ass, he would see pipes so dazzling he would ask the nurse to get his sunglasses."
---Shuttle Astronaut Mike Mullane

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#3 2005-06-07 21:25:49

BWhite
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From: Chicago, Illinois
Registered: 2004-06-16
Posts: 2,635

Re: Breaking news? - Admiral Steidle resigns

Fasten your seatbelts. Everything we have been saying here may become moot, very fast.


Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]

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#4 2005-06-07 21:34:04

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Breaking news? - Admiral Steidle resigns

Oh I wouldn't go that far, the basic course and what you ought to do to get there isn't going to be radically different.

All I can say is, anything other then the business-as-usual management is likly an improvement... if these are the same folks that wanted to fly Shuttle until 2025, then they ought to be tied to the Titan-IV launch pad for this summers' shot, not just "fired."


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#5 2005-06-08 11:11:17

BWhite
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From: Chicago, Illinois
Registered: 2004-06-16
Posts: 2,635

Re: Breaking news? - Admiral Steidle resigns

http://www.floridatoday.com/apps/pbcs.d … 07]Florida Today article:

Griffin said he, and people in the executive branch, were not happy with a timeline that called for the proposed Crew Exploration Vehicle to take almost a decade to get off the ground. Griffin deemed it unacceptable that the shuttle would retire in 2010 and the new ship would not fly humans until at least 2014, creating a four-year gap during which the United States would not have a manned spacecraft.

Griffin is speeding development to field the CEV by 2010, if possible. The new administrator also has assigned a small team of people he trusts to review most of the planning and decision-making to date related not only to the crewed spaceship but the entire moon-Mars initiative.

What are the odds that this "small team" agrees with Griffin's prior statements on heavy lift and the Planetary Society report?

http://planetary.org/aimformars/study-summary.html]Link prepared by:

William Claybaugh, Owen K. Garriott (team co-leader), John Garvey, Michael Griffin (team co-leader), Thomas D. Jones, Charles Kohlhase, Bruce McCandless II, William O'Neal, Paul A. Penzo

And from an April 20, 2005 Planetary Society press release:

One of the top issues Griffin addressed was the feasibility of a human mission to Mars as part of the administration’s “Moon, Mars, and Beyond” initiative. In response to a question from an Orlando Sentinel reporter, Griffin said: “Everything that I know to date about what it will cost us to do a Mars mission . . . is summarized in a Planetary Society report that Owen Garriott, an old and good friend, and I chaired on behalf of the Planetary Society with numerous coauthors.”


Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]

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#6 2005-06-08 11:17:12

BWhite
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From: Chicago, Illinois
Registered: 2004-06-16
Posts: 2,635

Re: Breaking news? - Admiral Steidle resigns

Another thought.  If Griffin was properly vetted by the Administration, his views on SDV would have been well known to them.

After all, he was co-team leader for writing a report that strongly suggested using a single stick Thiokol RSRM plus liquid upper stage for the CEV. It seems to me that if the plan is for the White House or DoD to force Griffin to reverse course on that opinion and go EELV, then we would be hearing very different things from Griffin, today, and Admiral Steidle would not have resigned.

Isn't reading tea leaves fun?


Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]

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#7 2005-06-08 11:29:06

clark
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Registered: 2001-09-20
Posts: 6,374

Re: Breaking news? - Admiral Steidle resigns

It seems to me that if the plan is for the White House or DoD to force Griffin to reverse course on that opinion and go EELV, then we would be hearing very different things from Griffin, today, and Admiral Steidle would not have resigned.

Perhaps the show down with Steidle is two fold- to remove the onus of the tanker deal coming in to cause Congressional oversight of the CEV contracts, and friction over how best to implement the VSE in the context of the Aldridge Commission findings.

I doubt Griffin could have moved Steidle without the White House’s approval or understanding. And Griffin is quickly ignoring many of the recommendations made by the report in lieu of a more NASA centric program (to be expected, ask for Mars, get the Moon).

However, how can Griffin manage CEV development, procurement, a nominal level of hard science, ISS construction and completion, AND SDVL development while operating an idle main stack plant?

Where is the money going to come from? (and if you say TV Bill, I will throttle you. tongue)

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#8 2005-06-08 11:46:11

BWhite
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From: Chicago, Illinois
Registered: 2004-06-16
Posts: 2,635

Re: Breaking news? - Admiral Steidle resigns

It seems to me that if the plan is for the White House or DoD to force Griffin to reverse course on that opinion and go EELV, then we would be hearing very different things from Griffin, today, and Admiral Steidle would not have resigned.

Perhaps the show down with Steidle is two fold- to remove the onus of the tanker deal coming in to cause Congressional oversight of the CEV contracts, and friction over how best to implement the VSE in the context of the Aldridge Commission findings.

I doubt Griffin could have moved Steidle without the White House’s approval or understanding. And Griffin is quickly ignoring many of the recommendations made by the report in lieu of a more NASA centric program (to be expected, ask for Mars, get the Moon).

However, how can Griffin manage CEV development, procurement, a nominal level of hard science, ISS construction and completion, AND SDVL development while operating an idle main stack plant?

Where is the money going to come from? (and if you say TV Bill, I will throttle you. tongue)

TV? Nah, not this NASA.

You raise legitimate issues, inherent in the VSE from January 2004.

CEV money flows into "da' stick" until someone gives it a name. Put an RL-60 on top, perhaps even a complete Delta IV upper stage. How long would that take, and how much to launch bags of sand with that creature?

Surely there are lots of RSRM segments laying around waiting for some future orbiter flight.

Where does the money come from? Curtailing the 25 - 30 orbiter flights tagged for ISS completion. Core complete or revised core complete. It comes from that section of the colored sand budget graph labeled STS/ISS.



Edited By BWhite on 1118253329


Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]

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#9 2005-06-08 12:01:02

clark
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Registered: 2001-09-20
Posts: 6,374

Re: Breaking news? - Admiral Steidle resigns

Where does the money come from? Curtailing the 25 - 30 orbiter flights tagged for ISS completion. Core complete or revised core complete. It comes from that section of the colored sand budget graph labeled STS/ISS.

So, lemme throw out some bad assumptions:

Shuttle retired by 2010, non-negotiable.
CEV development sped up to close 4-5 year gap between Shuttle retirement and human-rated capability.

If we curtail orbiter flights to the bare minimum, do we finish ISS construction at the “accelerated” rate and retire the Shuttle sooner than 2010? Or, do we slow down the rate of flights and construction to coincide with 2010 (and CEV final development)?

The reason I ask, or throw this out as it were, is that if we retire the Shuttle earlier than 2010, we’re back in the same boat as we were when CEV was slated for human rating in 2014. After Shuttle is retired, and until CEV human rating, there is a time span where US has no capability to send people into space.

So here is the conundrum, we need to retire the Shuttle early to free up fund for SDV development, but doing so means that the US suffers through some time where it has no capability to send people to space- which is what many people in positions of policy determination want to avoid.

So how do you solve this riddle?

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#10 2005-06-08 12:07:28

BWhite
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From: Chicago, Illinois
Registered: 2004-06-16
Posts: 2,635

Re: Breaking news? - Admiral Steidle resigns

Slow down orbiter flights. Last flight remains in 2010.

The standing army remains employed building and flying "da' stick" - - None of the standing army or infrastructure can be used for EELV, no VAB, no crawler, no Pad 39 etc. . .

With an SDV CEV, fixed overhead can do double duty, reduced orbiter flights and RSRM CEV test flights.

= = =

The ISS architecture is what gets curtailed. A slimmed down ISS.



Edited By BWhite on 1118254122


Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]

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#11 2005-06-08 12:11:54

clark
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Registered: 2001-09-20
Posts: 6,374

Re: Breaking news? - Admiral Steidle resigns

That would be a sight...

As the last Shuttle mission comes down, the first human rated CEV mission goes up.  big_smile

Need to think about this some more...

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#12 2005-06-08 12:12:04

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,433

Re: Breaking news? - Admiral Steidle resigns

Buy a human rated soyuz capsule and stick it on top of the srb booster with liquid upper stage to push the capsule into orbit. Every thing is already tested just needs to be connected together for use. Use a third party buyer for the capsule, as to not ire anybody about the iran dealings and move on to human space flight once more.

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#13 2005-06-08 20:12:51

RobertDyck
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From: Winnipeg, Canada
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Posts: 7,936
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Re: Breaking news? - Admiral Steidle resigns

Isn't Admiral Steidle the guy who said at the last Mars Society conference in Chicago that NASA will pay contractors outside the US? As someone in Canada who wants to be a NASA contractor, I'm a bit concerned. I really like what I've seen of Mike Griffin so far, but I am concerned about getting funding.

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#14 2005-06-10 10:26:39

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,433

Re: Breaking news? - Admiral Steidle resigns

A little more on the internal movement of higher ups.
[url=http://www.chron.com/cs/CDA/ssistory.mpl/space/3219207] NASA moving leaders to help reach new goals
Reassignments and resignations are key to Griffin's exploration plans[/url]

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#15 2005-06-10 18:01:41

Grypd
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From: Scotland, Europe
Registered: 2004-06-07
Posts: 1,879

Re: Breaking news? - Admiral Steidle resigns

More cuts and the first layoffs.

http://www.floridatoday.com/apps/pbcs.d … ews02]NASA fires culture change consultants

Interesting this actually means another accident that is the result of a lack of safety preparation and thought will mean that Griffin has to take the blame. Another point is this could be NASA not willing to be told what to do. Or just a means to save some hard cash.


Chan eil mi aig a bheil ùidh ann an gleidheadh an status quo; Tha mi airson cur às e.

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#16 2005-06-10 21:37:41

srmeaney
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Posts: 976

Re: Breaking news? - Admiral Steidle resigns

Quote 
Griffin said he, and people in the executive branch, were not happy with a timeline that called for the proposed Crew Exploration Vehicle to take almost a decade to get off the ground. Griffin deemed it unacceptable that the shuttle would retire in 2010 and the new ship would not fly humans until at least 2014, creating a four-year gap during which the United States would not have a manned spacecraft.

Griffin is speeding development to field the CEV by 2010, if possible. The new administrator also has assigned a small team of people he trusts to review most of the planning and decision-making to date related not only to the crewed spaceship but the entire moon-Mars initiative.

As suspected, a cull at NASA... Just take the engineers out back and put them down humanely.

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#17 2005-06-11 08:19:32

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,936
Website

Re: Breaking news? - Admiral Steidle resigns

More cuts and the first layoffs.

http://www.floridatoday.com/apps/pbcs.d … ews02]NASA fires culture change consultants

Interesting this actually means another accident that is the result of a lack of safety preparation and thought will mean that Griffin has to take the blame. Another point is this could be NASA not willing to be told what to do. Or just a means to save some hard cash.

A consulting firm to train managers about culture? A lot of organizations waste a lot of management time on training or seminars that are air-fairy fluffy crap. If managers are not capable of listening when an engineer or safety inspector reports a safety problem, the manager needs to be reassigned or fired. A decision that causes failure of a multi-million dollar EELV launch should result in reassignment to something like mailboy, janitor, lawnmower, picking up garbage from the grounds, etc. A manager who fails to listen to a safety report causing loss of life should result in being fired, minimum.

When I was Technical Architect on the year 2000 Project Management Office of the provincial telephone company, the testing manager tried to bypass me and hire someone else to evaluate software tools for testing. That was specifically in my job description. Project directors also had fights over jurisdictions, and team leaders were challenging the authority of project directors over them. The PMO director sent all his staff on a week-long seminar to work together and deal with jurisdictional conflicts. Afterward the testing manager continued the same problem. The team leader who challenged authority of the project directors continued to do so, senior project managers (between team leaders and project directors) not only challenged authority of project directors, but the PMO director himself. Nothing was resolved, the seminar was a waste of time and money.

Meetings in the executive office board room rotated who was chair, at the meeting I chaired one of the project managers didn't show up but sent a systems analyst instead (below team leader). He said they're replacing their program rather than doing a year 2000 fix. The project director in charge of evaluating whether replacement projects would be complete in time asked for detailed status and progress reports. He refused and said they already had money from the steering committee for the replacement. I took offence at the blatant disrespect for the Project Management Office, so I pointed out roles and responsibility: Janice's job was to evaluate replacement projects such as his and if in her opinion they weren't going to be ready on time she would take away their year 2000 money and form a fix project for the existing computer program. I pointed out the steering committee gave this office responsibility for Year 2000 oversight, and authority had been confirmed by the executive VP, President, and the CEO sent a letter to all management staff stating this and requiring them to cooperate. The analyst didn't like that at all. I wasn't invited to further meetings much less chairing them. After that conflicts among PMO staff got worse, primarily due to the fact that their authority was ignored so they fought among each other for what little was perceived to be left. The PMO director had been promoted from one of the senior project managers. He was the only one who applied for the position. However, I was there when a group of 3 senior project managers told the PMO director to his face that they considered him to be nothing but another project manager. They refused to acknowledge his promotion or his authority over them. He said nothing. Back at the seminar, when it started the executive VP showed up to say in front of the entire PMO staff that he was concerned the PMO director would be able to hold onto the authority he was given. The executive VP was the PMO director's immediate supervisor. When I pushed for the PMO to hold onto the authority it was given I was fired. After the testing manager pushed for adequate testing, he was fired. The result was the entire billing system failed on January 1, 2000, due to a year 2000 bug. The phone company was not able to produce bills for 3 weeks in January. I'm sure telephone customers didn't mind, but do you know how much money it costs a multi-billion dollar company per week when its entire revenue is cut off? The whole point of the year 2000 project was to prevent that. This is where I get to tell them "I told you so." The point is it demonstrates how a management consulting group or seminars are really ineffective. It really takes senior management that can establish clear lines of authority and responsibility, and knock heads when subordinates challenge the authority of their superior. When a technical guy reports a problem that will lead to failure, act on it rather than pandering to middle managers protecting their little empire.

I applaud Mike Griffin's action.

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#18 2005-06-11 09:16:56

RobS
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From: South Bend, IN
Registered: 2002-01-15
Posts: 1,701
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Re: Breaking news? - Admiral Steidle resigns

As suspected, a cull at NASA... Just take the engineers out back and put them down humanely

No, no, just the opposite. He's firing the managers and putting engineers into the management positions, just like in the Apollo days. That way spacecraft construction is coordinated by people who know how to build them.

         -- RobS

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#19 2005-06-11 09:21:20

Chazbro38
Member
From: Highland Park, IL
Registered: 2005-04-03
Posts: 27

Re: Breaking news? - Admiral Steidle resigns

People, people, the current SRB as a first stage is a technical impossibility for one simple reason, its design is incompatible with open loop guidance and control.

You have to remember that it was developed exclusively to be an integral component of a FOUR piece stack. 95% of the guidance, control, load balancing and of course the THROTTLING capability of that stack was provided by the orbiter.

If you are still confused, just remember the corkscrew contrail that resulted after the Challenger explosion and that SRB's prematurely seperated and flew off on their own. They are designed with extremely limited control capability based on gimballing the thrust nozzle along only axis between 0 and 180 degrees.

I would like anyone to explain how the current SRB can overcome these technical/engineering deficiencies to provide a capabilty as a man-rated 1st stage.

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#20 2005-06-11 12:11:09

Rxke
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From: Belgium
Registered: 2003-11-03
Posts: 3,669

Re: Breaking news? - Admiral Steidle resigns

http://www.washingtonpost.com/wp-dyn/co … 01911.html

20 got the goodbye letter so far

The sources also confirmed that Associate Administrator for Science Alphonso V. Diaz, who oversees the Mars rovers, the Cassini mission to Saturn and other exploration projects, will be replaced. His successor has not been chosen.

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#21 2005-06-11 13:02:04

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Breaking news? - Admiral Steidle resigns

People, people, the current SRB as a first stage is a technical impossibility for one simple reason, its design is incompatible with open loop guidance and control.

You have to remember that it was developed exclusively to be an integral component of a FOUR piece stack. 95% of the guidance, control, load balancing and of course the THROTTLING capability of that stack was provided by the orbiter.

If you are still confused, just remember the corkscrew contrail that resulted after the Challenger explosion and that SRB's prematurely seperated and flew off on their own. They are designed with extremely limited control capability based on gimballing the thrust nozzle along only axis between 0 and 180 degrees.

I would like anyone to explain how the current SRB can overcome these technical/engineering deficiencies to provide a capabilty as a man-rated 1st stage.

Thats nice Robert, but you could have summarized that long history to something along the lines of "lower level management was causing trouble by defying authority, the company sent everybody to a seminar to try and show them why chain of command is nessesarry, and when it didn't work the Y2K bug cost the company millions."

If the SRB launcher was built in order to launch crew, you obviously wouldn't use the stock Shuttle booster, and some changes would certainly be made. Changing the guidence software for a five rather then four segment shouldn't be hard, it would only involve some minor changes to the physical constants of the rocket the program uses. The SRM gimbled nozzle is probobly good enough by itself, but Thiokol wants to add fins to the base of the booster if you would look at their rendering. Throttling would be nice, but as long as you don't mind putting your crew under a little extra G-force on launch, it really isn't nessesarry.

The concept of man rating boils down to the numbers, that is, how many times will there be a crew casulty for a number of times the launcher is used. If the probability is low enough, like 1/300th chance, then that vehicle is by definition "man rated." While the Shuttle SRB does not have a means of shutting down, and the higher acceleration will demand a more violent escape rocket in the event of trouble, the fact remains that the SRB (when used within spec) is the most reliable rocket of its size ever devised. Its sheer reliability, which is really quite impressive, goes a long way to making the vehicle "man rated."

I personally, however, am not real fond of the idea because you can't shut the thing off, and if it were to fail (fuel grain or casing weld rupture for instance) it would fail in a big enough way that the escape plan survival probability (which is difficult to estimate accurately) is probobly lower then with liquid launch vehicles. Unfortunatly, due to the provision that CEV should be launched with its "Service Module," there are no all-liquid fueled vehicles powerful enough to launch CEV except the Delta-IV HLV, and that would be both expensive and risky.

Lockheed however in an earlier VSE proposal believes that the Atlas-V could be substantially alterd, turning it into an "American Zenit" with liquid hydrogen upper stage, that would be able to lift CEV with no solid boosters. It is unlikely that Boeing's Delta-IV Medium could reach this performance level.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#22 2005-06-11 18:57:13

Chazbro38
Member
From: Highland Park, IL
Registered: 2005-04-03
Posts: 27

Re: Breaking news? - Admiral Steidle resigns

Who is Robert?

Any how, NASA astronaut Scott Horowitz claims to have run the performance numbers of the SRB on his computer and found that, in his words, it would be “a hell of a ride.” The SRBs burn out after just over two minutes, and although powerful, a single SRB doesn’t have enough performance alone to put a manned spacecraft into orbit. At burnout “you’re going about Mach 18 and pulling about TWENTY g’s,” he said. So much for man-rating the SRB's!

(I assume that a man-rating assumes that a man inside would actually survive the trip to LEO--but I could be mistaken about that little detail. Maybe someone could set me straight on that!)

In addition, turning the SRB into a launch vehicle requires an upper stage.

Despite the discussion within NASA and elsewhere about using the SRB to launch the CEV, it’s not clear whether there’s sufficient momentum behind the idea to at least allow further studies, let alone selection of the concept for development. ATK Thiokol is strongly behind the idea because it gives new life for the SRB—a significant portion of their business—once the shuttle is retired around the end of the decade(Thiokol is behind this absurd concept, Oh there's a surprise!).

There are other technical issues that a SRB-derived launch system would have to address, notably the development of a new upper stage. However, in the long run the bigger challenges that an SRB-based launcher might have to face are perceptions: that the SRB is an old technology, best left to the past; that solid-propellant motors like the SRB, which can’t be turned off once ignited, are unsuited for manned spaceflight applications. All of this equals more billions spent and more years of delay for a CEV. I guess I'm answering my own question!

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#23 2005-06-11 21:47:06

GCNRevenger
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From: Earth
Registered: 2003-10-14
Posts: 6,056

Re: Breaking news? - Admiral Steidle resigns

Well of course it would be pulling extremely high-g loads if it wern't pushing an upper stage or payload that weighed many tons. The acceleration of the booster alone is irrelivent. And certainly it would require an upper stage, the "B" in SRB stands for booster after all. Building such a stage shouldn't be too hard, you could even perhaps take the stock Delta-IV Heavy upper stage, swap out the RL-10's for RL-60's, and modify the guidence software.

The standard SRB design is also optimised for maximum thrust in a short amount of time; this could be changed to reduce thrust and increase burn time by merely changing the shape of the fuel casting. Right now, the fuel casting (or "grain" in the biz) has channels down its length to increase the surface area, which increases the rate of combustion, which increases thrust at the expense of burn time and increased pressure. By changing the shape of the fuel casting, you could lower the thrust and at the same time lower the operating pressure, which would increase safety.

Although the issue about being unable to shut down the booster is a signifigant one, and the high accelerations involved are a concern, dismissing the SRB-Launcher option out of hand is uncalled for; the SRB remains today the most reliable rocket of its size ever developed by man, and is the only rocket cheap and large enough for CEV that is being flown in the United States today.

I think that the preception of the SRB being "old" being a problem is unfounded and a bit silly too, BTW.


[i]"The power of accurate observation is often called cynicism by those that do not have it." - George Bernard Shaw[/i]

[i]The glass is at 50% of capacity[/i]

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#24 2005-06-11 23:14:50

BWhite
Member
From: Chicago, Illinois
Registered: 2004-06-16
Posts: 2,635

Re: Breaking news? - Admiral Steidle resigns

Who is Robert?

Any how, NASA astronaut Scott Horowitz claims to have run the performance numbers of the SRB on his computer and found that, in his words, it would be “a hell of a ride.” The SRBs burn out after just over two minutes, and although powerful, a single SRB doesn’t have enough performance alone to put a manned spacecraft into orbit. At burnout “you’re going about Mach 18 and pulling about TWENTY g’s,” he said. So much for man-rating the SRB's!

(I assume that a man-rating assumes that a man inside would actually survive the trip to LEO--but I could be mistaken about that little detail. Maybe someone could set me straight on that!)

In addition, turning the SRB into a launch vehicle requires an upper stage.

Despite the discussion within NASA and elsewhere about using the SRB to launch the CEV, it’s not clear whether there’s sufficient momentum behind the idea to at least allow further studies, let alone selection of the concept for development. ATK Thiokol is strongly behind the idea because it gives new life for the SRB—a significant portion of their business—once the shuttle is retired around the end of the decade(Thiokol is behind this absurd concept, Oh there's a surprise!).

There are other technical issues that a SRB-derived launch system would have to address, notably the development of a new upper stage. However, in the long run the bigger challenges that an SRB-based launcher might have to face are perceptions: that the SRB is an old technology, best left to the past; that solid-propellant motors like the SRB, which can’t be turned off once ignited, are unsuited for manned spaceflight applications. All of this equals more billions spent and more years of delay for a CEV. I guess I'm answering my own question!

http://www.geocities.com/launchreport/weblog.html]Link

As for momentum, the idea of an upper stage on an SRB was strongly touted by the Planetary Society report released in July 2004. Michael Griffin was the co-leader of the team that prepared that report.


Give someone a sufficient [b][i]why[/i][/b] and they can endure just about any [b][i]how[/i][/b]

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#25 2005-06-12 21:57:06

GregM
Member
Registered: 2005-01-16
Posts: 30

Re: Breaking news? - Admiral Steidle resigns

Gentlemen, gentlemen

If they really want it to, "The Stick" can be made to work.

Yes, if you put a person in the place of parachutes on a single STS SRB as it is now, that person would be undoubtedly crushed in flight like a bug. No question about it. And yes, it currently has one axis gimbal capability. And yes, it currently has a limited self guidance capability. That’s why no one in their right mind would ever do such a thing. It’s the world’s largest skyrocket when taken on its own as it is currently configured – not a human LV.

That said….

There is nothing that would stop it from becoming one in very short order. The issues:

-Safety. This has three aspects. Firstly, overall SRM reliability. It is in a nutshell, excellent - possibly the best in the history of rocketry. It is already man rated, although modifications will require re-certification. The SRM is also one of the most thoroughly understood LV motors in the history of rocketry – bar none. Given enough flights, one will inevitably fail however, so…. Secondly, abort safety. I read that there is a lot of concern here about being unable to shut off a malfunctioning solid motor. This is incorrect. Every solid motor has a linear charge placed along the length of the casing on the outside. If that charge is blown, it tears open the length of the casing and the thrust out of the nozzle is cutoff. Happens almost instantaneously once activated. Since the CRV is going to have a launch escape system, the CRV can be pulled away from the errant booster, and the linear charge blown milliseconds later – basically cutting the thrust off of the malfunctioning SRB. Thirdly, there is no additional safety in having a liquid-fueled booster unless it is a multi-engine liquid booster with engine-out-to orbit capability. In that capacity, such an LV  can shut a sick engine down in flight and continue on to orbit.  Very few LV’s have ever had that luxury – Saturn, STS, & Proton I believe (and none of even these has this capability during the entire boost phase). Every other malfunctioning LV is going into the Atlantic no matter if it is liquid fueled or solid fueled – and a launch escape system for the CRV is going to be the only thing to save the crew’s lives in any such scenario.  Same with a sudden catastrophic LV failure: if it’s gonna blow up, it’s gonna blow up – liquid or solid fueled. Again, only a good launch escape systems is gonna save the crew.

- Thrust vectoring. There are several ways to deal with this, none of which involve the current SRB nozzle gimbal system. One crude method is to spray liquid fuel at right angles into the thrust stream at the nozzle. Titan 3 used this technique successfully for 30 years. A more likely scenario however is simply to develop a 2-axis gimbling nozzle for the motor. This may end up being the most expensive upgrade in developing such a vehicle, but it can be done. Adding fins would also be a help.

- Acceleration. Be aware that solid motor burn rate can be controlled these days by constructing the solid fuel in different shapes and mixtures. That, coupled with the fact that the SRB will be lofting at least 70,000 pounds of second stage and spacecraft should allow for a wild, yet acceptable ride. Could be looking at 3-6 G’s for crewmembers. No worse than Saturn.

A few other items – Griffin wants CEV flying in 2010-2011. So they need a booster that can be developed and man-rated in very short order using existing technology and facilities,  and at as low a cost as possible. The Stick looks very good in that regard.

In my opinion, the bigger developmental issue for such a vehicle would be the man rating for the second stage. It would be this stage that would be doing the bulk of the flying – likely burning for up to 8 or 10 minutes, depending on the launch profile.

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