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Space Forum / Shuttle / May 2005Scott Horowitz 'Duhs' Congress and Undoes the Space Shuttle
<http://www.spaceref.com/news/viewsr.html?pid=16645> "In combination with the heavy lift launch capability, it is equally important to leverage existing human rated propulsion elements and focus on the safest way to put the crew in space. Utilizing a single space shuttle reusable solid rocket motor for the first stage of the crew launch vehicle is an ideal application of simplicity. The motor is already human rated and has an outstanding proven safety and reliability record. Add to this reusable first stage a previously developed human rated 2nd stage rocket engine, either a simplified version of the Apollo engine that took astronauts to the moon, the J-2S, or a space shuttle main engine and you have a very simple, cost effective launch vehicle solution, built upon human rated heritage." Pardon me, but I have a couple of questions for Congress to ask. 1) Would the one space shuttle main engine remain cost-effectively reusable? During first stage and possibly early second stage, experience warns us that the CEV would impose upon the stack at least some roll-inducing limitations of a lifting body. (For first-stage, RCS roll control is not man-rated.) 2) What is Scott's cost-effective proposal for first-stage roll control, given the above single-SRB, single-main-engine, boost configuration? Challenger's Ghost > <http://www.spaceref.com/news/viewsr.html?pid=16645> > [quoted text clipped - 14 lines] > 1) Would the one space shuttle main engine remain cost-effectively > reusable? It probably isn't cost-effectively reusable today, as flown on shuttle! But Scott Horowitz's mention of an SSME option is telling. It indicates to me that ATK has discovered cost issues with the J-2S option. > During first stage and possibly early second stage, experience warns us > that the CEV would impose upon the stack at least some roll-inducing [quoted text clipped - 4 lines] > control, given the above single-SRB, single-main-engine, boost > configuration? I've read that roll control would be provided by a thrust module mounted on the second stage - the same way that Atlas II worked during the Atlas sustainer phase for example. Scott Horowitz, an ex-astronaut, is an effective advocate for SRB-CEV. What is needed now are comparable advocates for Delta IV-CEV and/or Atlas V/CEV to debate the merits - and to mention that their rockets already exist while Scott's is going to require mucho bucks to create. By going to the media and to Congress, ATK is currently outflanking the EELV manufacturers. It's time for them to enter the fight! - Ed Kyle > > 1) Would the one space shuttle main engine remain > > cost-effectively reusable? > > It probably isn't cost-effectively reusable today, as flown > on shuttle! I don't see that as a problem with the engine itself at this point; but regardless, what is Scott's plan? Do you think his strategy is to use up (waste as non-reusable) the ones on hand -- when no more shuttles are flown? > > 2) What is Scott's cost-effective proposal for > > first-stage roll control, given the above single-SRB, [quoted text clipped - 4 lines] > way that Atlas II worked during the Atlas sustainer > phase for example. I'd sure appreciate it if you'd describe that a bit for me. I may know just enough about that to be dangerous (hopefully not to myself). Was Atlas II flown with the Agena? If so, during approximately what years? I may have some applicable telemetry experience to relay, from my early years with Lockheed as a Flight Test Analysis Engineer. Thanks for the interest in my post. Challenger's Ghost > > > 2) What is Scott's cost-effective proposal for > > > first-stage roll control, given the above single-SRB, [quoted text clipped - 6 lines] > > I'd sure appreciate it if you'd describe that a bit for me. More research indicates that you refer to hydrazine thrusters, which would also be used for collision avoidance with the CEV (as they apparently were for Atlas II payloads). I'm not sure how well this would work out for man-rating. > Was Atlas II flown with the Agena? If so, during approximately what > years? I may have some applicable telemetry experience to relay, from > my early years with Lockheed as a Flight Test Analysis Engineer. I found the following at GlobalSecurity.org: <<Atlas F - Testing of the Atlas F ICBM began in August 1961 with completion coming by the end of 1962. This marked the end of the five-year missile test program. As with the Atlas E, many were subsequently used for space launch operations. The Atlas F used MA-5 engines on the booster and the sustainer.>> <<All Atlas engines of the Rocketdyne MA-5 propulsion system are ignited before liftoff. The two booster engines and the single sustainer engine share the same propellant tanks. The booster engines are jettisoned about two and half minutes into flight after 5.3g acceleration is attained. The sustainer burns until propellant depletion. Two small vernier rockets assist in the early roll maneuver to the desired azimuth and provide roll control during the sustainer phase. Propellants for all engines are LO2 and RP-l.>> <<The Centaur D-lA, used in conjunction with Atlas G, incorporates the following improvements: elimination of hydrogen peroxide boost pumps in the propellant supply system; replacement of hydrogen peroxide reaction control system with an equivalent hydrazine system; incorporation of a silver throat cast insert in the Pratt & Whitney engines (new designation: RL 10A-3-3A).>> As I understand it, Atlas G launches did not begin until 1984. New Question: With regard to a SRB/ME/CEV configuration, what are the man-rating problems with reverting to a roll-control technology similar to that used for Atlas F (i.e., no hydrazine)? > Challenger's Ghost > > > I've read that roll control would be provided by a > > > thrust module mounted on the second stage - the same > > > way that Atlas II worked during the Atlas sustainer > > > phase for example. > > > > I'd sure appreciate it if you'd describe that a bit for me. <snip> > <<The Atlas F used MA-5 engines on > the booster and the sustainer.>> [quoted text clipped - 7 lines] > maneuver to the desired azimuth and provide roll control during the > sustainer phase. Propellants for all engines are LO2 and RP-l.>> Since vernier rockets only "assist in the early roll maneuver," apparently Atlas F derivatives depend primarily on the main propulsion engines for roll control. With only one SRB firing during first-stage, and with only one main engine firing during second stage, where does the primary roll control reside for first-stage -- in the SRB/ME/CEV concept of Scott Horowitz? Challenger's Ghost > More research indicates that you refer to hydrazine thrusters, which > would also be used for collision avoidance with the CEV (as they > apparently were for Atlas II payloads). I'm not sure how well this > would work out for man-rating. How is Hydrazine on a shuttle-derived launcher any different than hydrazine used on the shuttle today WRT to man-rating? The hydrazine "problem" seems to be more of a processing cost issue than safety. (Due to the Hazmat reqts, etc). tom cuddihy > New Question: With regard to a SRB/ME/CEV configuration, what are the > man-rating problems with reverting to a roll-control technology similar > to that used for Atlas F (i.e., no hydrazine)? > > > Challenger's Ghost > > More research indicates that you refer to hydrazine thrusters, which > > would also be used for collision avoidance with the CEV (as they [quoted text clipped - 5 lines] > "problem" seems to be more of a processing cost issue than safety. (Due > to the Hazmat reqts, etc). Well, given the Shuttle doesn't meet current NASA guidelines for man-rating, the question is meaningless. In any case, for something like the CEV, processing cost will be a big issue (if they're smart.) > tom cuddihy > [quoted text clipped - 4 lines] > > > > > Challenger's Ghost > > More research indicates that you refer to hydrazine thrusters, > > which would also be used for collision avoidance with the CEV [quoted text clipped - 5 lines] > "problem" seems to be more of a processing cost issue than safety. > (Due to the Hazmat reqts, etc). Thanks, I had begun to think no one would question me about that. I would also be concerned about an unexplained claim that hydrazine thrusters could supply adequate first-stage roll control for Scott's shuttle-derived cargo carrier (single-SRB first stage, single-ME second stage, side-mounted cargo). I like the "Einsteinian" simplicity of Scott's cargo carrier, but I see no plan for primary first-stage roll control of that stack either. To get back to your question, let me say that my understanding (thus far) of the dozen or so hydrazine thrusters (used in conjunction with the Atlas II sustainer) is that they were mostly associated with a Centaur stage. In other words, they were not the nose wagging the dog; they were just more roll augmentation forward (than the two hydrogen peroxide thrusters they replaced) of the first-stage roll control provided by the stage-and-a-half Atlas main engines. Until someone provides clarification, I'm going to assume that more (hydrazine) thrusters were needed because Centaur was a bigger vehicle. My experience with the shuttle's inadequately planned for Centaur stage was bad enough (no hydrazine); I'd hate to see a solid-fuel, LOX/LH2, hydrazine combination integrated software-wise and hardware-wise (prelaunch) without more to go on. To summarize, don't kid yourself. Hydrazine usage involves more than processing-cost and safety issues; it involves complex design issues. *They* need to be "Einsteinian." I can't give you the answer you'd like to your question without a better definition of "hydrazine on a shuttle-derived launcher," i.e., one which is a bit more concrete. As it is, I'm left to someone's imagination in that regard (mostly my own, I guess). How about using the nose portions of leftover ETs as disposable aerodynamic cocoons for the CEVs? That might be cost-effective for roll control, but would collision avoidance be impossible? For the shuttle, hydrazine is used to power the HPUs used in the SRBs' TVC systems. So far as I know, to date that usage has been satisfactory -- with regard to man-rating. That certainly doesn't mean they can be carelessly serviced. I hope some of this helps you, Tom. Challenger's Ghost > But Scott Horowitz's mention of an SSME option is telling. It indicates to me that ATK has discovered cost issues with the J-2S option. No. It's just one of the trade options. The SSEM has considerably higher thrust than the J-2S, so if the payload gets bigger/heavier, then the RSRM-derived stack might need a bigger second stage engien to get it into orbit. That's the trouble for the booster people jsut now... nobody knows what we're boosting yet. > What is needed now are comparable advocates for Delta IV-CEV and/or Atlas V/CEV to debate the merits - and to mention that their rockets already exist Atlas V Heavy already exists? Atlas/Delta versions capable of boosting 30 tons already exist? >> What is needed now are > comparable advocates for Delta IV-CEV and/or [quoted text clipped - 3 lines] > Atlas V Heavy already exists? Atlas/Delta versions capable of boosting > 30 tons already exist? Relatively straightforward development and implementation. For the most part, Atlas V Heavy >does< exist. --Damon > > What is needed now are > comparable advocates for Delta IV-CEV and/or [quoted text clipped - 3 lines] > Atlas V Heavy already exists? Atlas/Delta versions capable of boosting > 30 tons already exist? 30 tons .... sheesh. The official spec is still 20 tons liftoff mass for CEV, and that should be enough. I have to say that I suspect that Griffin mentioned 30 tons in his talk as a signal of his intention to keep shuttle-derived alive. 30 tons levels the playing field for shuttle-derived supporters, forcing new EELV development effort if those rockets are to compete for the work - but it also means unneccesarily higher launch costs for ISS missions. ISS will be the first CEV duty. The lunar mission is an Iraqi-War-sized idea, dollarwise, that will more than likely continue to recede into the future until and unless the U.S. Government stops allowing China to bleed away the U.S. economy. 1.5% of our GDP is gone to China now - $2 billion of wealth transferred each day - enough each day to almost run NASA's shuttle program for a year. When Greenspan eases, he lights up China's economy rather than ours. If the U.S. doesn't get it's economy solved, the Moon will be unaffordable. How can a country spend billions and billions on lunar exploration when it can't even pay its people's social security? Etc. As for Atlas, there is already an Atlas V Medium powerful enough to do the 20 tons. And Delta IV Heavy, of course, can do it. It cost billions to develop these rockets. Why not use them for something? - Ed Kyle > ISS will be the first CEV duty. > Oh, we can hope. CEV flight number 1 goes to ISS, and bolts on the deorbit motors... Mmmmm......... >If the U.S. doesn't get it's economy solved, the >Moon will be unaffordable. How can a country spend >billions and billions on lunar exploration when it >can't even pay its people's social security? Cancel the unConstitutional and immoral Social Security pyramid scheme. There. Problem solved. > Cancel the unConstitutional and immoral Social Security pyramid scheme. > There. Problem solved. Only if it would be OK for my parent's in-law to move in with you... :) - Ed Kyle > > [quoted text clipped - 9 lines] >Only if it would be OK for my parent's in-law to >move in with you... :) Imagine if you'd earned 15% more throughout your working life. You could buy 'em off. > >>Cancel the unConstitutional and immoral Social Security pyramid > >> [quoted text clipped - 7 lines] > Imagine if you'd earned 15% more throughout your working life. You could > buy 'em off. Too bad that the actual expected earnings rate will be around half of what SS would pay. This has been the experience of both Britain, which went with private accounts back in the early 80's, and several South American countries which tried variations of the same thing. Also, pity your retirement if it happens to begin during a major downswing in the stock markets, like the dot-com bust just a few years ago, the meltdown in the early 90's, the recession in the 80's, etc, etc. Of course, if you can time your getting old to coincide with market upswings then it's a better deal than SS. JazzMan  Signature********************************************************** Please reply to jsavage"at"airmail.net. Curse those darned bulk e-mailers! ********************************************************** "Rats and roaches live by competition under the laws of supply and demand. It is the privilege of human beings to live under the laws of justice and mercy." - Wendell Berry ********************************************************** > > [quoted text clipped - 26 lines] >around half of what SS would pay. This has been the >experience of both Britain, Except, of course, that's irrelevant. Look to Galveston, Texas: the civil servants there were able to opt out of Social Security. They are doing notably better without it than they woudl if they had it. Just because the Brits can't figure out how to get along without a nanny-state holdign their hand doesn;t mean *nobody* can. >pity your retirement if it happens to begin during a major >downswing in the stock markets, So work a few years more. Remember, you were not *supposed* to recieve Social Security. When the program began, the age at which you'd begin to draw from it was several years *beyond* average life expectancy. So today it should probably be in the region of 86 or 90 years old before SS kicks in. >>> >>> [quoted text clipped - 4 lines] >Too bad that the actual expected earnings rate will be >around half of what SS would pay. Assume also that you work for decaddes and die before drawing Social Security. In the current scam, all that money you paid in goes nowhere. In a better world with no Social Security, that money that woudl ahve gone into SS would be whewrever you put it, available for your depenants to use. Assuming you didn;t waste it all on beer and hookers, of course. > Assume also that you work for decaddes and die before drawing Social > Security. In the current scam, all that money you paid in goes nowhere. > In a better world with no Social Security, that money that woudl ahve > gone into SS would be whewrever you put it, available for your depenants > to use. Assuming you didn;t waste it all on beer and hookers, of course. So, are you saying that you regret wasting all your money on beer and hokers? JazzMan Signature********************************************************** Please reply to jsavage"at"airmail.net. Curse those darned bulk e-mailers! ********************************************************** "Rats and roaches live by competition under the laws of supply and demand. It is the privilege of human beings to live under the laws of justice and mercy." - Wendell Berry ********************************************************** > > [quoted text clipped - 11 lines] > > No. I'm saying I regret wasting all that money on Social Security. Beer and hookers would have been a better use of it for me. >>> Assume also that you work for decaddes and die before drawing Social >>> Security. In the current scam, all that money you paid in goes nowhere. [quoted text clipped - 7 lines] > No. I'm saying I regret wasting all that money on Social Security. Beer > and hookers would have been a better use of it for me. We'll expect you to remember to be consistent when those checks come made out to you someday, then. No doubt you'll return them uncashed. While we're at it, if you ever end up disabled before retirement, we can count on you not to apply for social security disability too, right? SignatureHerb Schaltegger, GPG Key ID: BBF6FC1C "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety." - Benjamin Franklin, 1759 <http://www.individual-i.com/> >We'll expect you to remember to be consistent when those checks come >made out to you someday, then. Yeah. Like *that* will happen. Hopefully it won't. >While we're at it, if you ever end up disabled before retirement, we >can count on you not to apply for social security disability too, >right? > Probably. However, there's a flaw in your argeument. If someone stole your money, and then drove by and threw some of that money back at you, would you take it? Probably. But then, you'd probably have been happier if they had never stolen from you in the first place. |
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