PMN1 - 16/11/2005 9:48 AMYou have the chance of redesigning the STS but you have got to keep to the same basic configuration - central core, boosters (unless you can avoid them) and a winged return vehicle - what changes would you make to improve operations and any guestimates on changes (if any) to operating costs?
Flightstar - 16/11/2005 11:56 AMQuotePMN1 - 16/11/2005 9:48 AMYou have the chance of redesigning the STS but you have got to keep to the same basic configuration - central core, boosters (unless you can avoid them) and a winged return vehicle - what changes would you make to improve operations and any guestimates on changes (if any) to operating costs? Crew Escape System. No idea on the cost.
FransonUK - 16/11/2005 10:15 AMNone. Given your parameters.
nacnud - 16/11/2005 8:16 PMJust a note about the Energia. The Zenith boosters were also planned to be reuseable. In the picures of Energia you can see big grey bulges on the Zeniths, these were to house the parachutes but the system was never fully developed.
nacnud - 16/11/2005 7:36 PMOnly if the flight rate increases dramaticaly would some thing like a liquid flyback booster become viable.
Avron - 17/11/2005 12:14 AMChanges1) Place the SSME's at the base of the tank and place the Orbiter on top of the tank - inline - bye-bye foam issue2) Make the lower structure ( at least) of the Orbiter out of Titanium with a disposable heat shield and leading edges that could be bolted on for the next flight -- bye-bye tile issue - reduce the corrosion issue3) More modular design at macro level - plug in - plug out crew compartment - wings, airlock etc.4) Always wondered, it the top surface of the wings could be lined with solar pannels.5) Four SRB's6) Go around landing capability7) Launch escape system, like Apollo/CEV, a lot bigger, to pull away the above crew compartment module from the rest of the Vehicle Plug in extended crew compartment moduleenough...
Avron - 16/11/2005 11:14 PMChanges1) Place the SSME's at the base of the tank and place the Orbiter on top of the tank - inline - bye-bye foam issue
rsp1202 - 16/11/2005 8:50 PMAs to Chris' question re: SRB/CLV, the idea of using SRBs as a manned booster has become the linchpin of future manned ops. I've raised the question elsewhere regarding its viability. but have been assured by space "pros" that the booster will be stable in flight, the ride will be benign, and most importantly that the astronauts themselves support the concept."Everyone" seems to be for it, even though it's the least talked about part of the new architecture plan. It's considered a "given." Okay. With so many assurances, my concerns have doubled. It sounds a whole lot like the sales job Adminstrator Fletcher was making prior to the shuttle coming online.So the test schedule for the CLV/SRB becomes the pacing item for everything to follow. The J2 second stage design and test follows that in importance. I worry over that more than whether Constellation and Magnum will ever fly.
PMN1 - 17/11/2005 1:54 PMQuoteAvron - 16/11/2005 11:14 PMChanges1) Place the SSME's at the base of the tank and place the Orbiter on top of the tank - inline - bye-bye foam issueWhats the refurbishment costs for SSME's (not to mention SRB's) vs expending them each time?
PMN1 - 17/11/2005 1:17 PMWould there be a case for reducing the payload capacity of the orbitter but keeping the ovearll booster the same size - how often was the full capacity used in a manned launch that couldn't have been handled by an unmanned cargo pod (if there was one)?
PMN1 - 17/11/2005 2:17 PMWould there be a case for reducing the payload capacity of the orbitter but keeping the ovearll booster the same size - how often was the full capacity used in a manned launch that couldn't have been handled by an unmanned cargo pod (if there was one)?
kraisee - 17/11/2005 1:18 PMQuotenacnud - 16/11/2005 7:36 PMOnly if the flight rate increases dramaticaly would some thing like a liquid flyback booster become viable.EPA are already harping on about the cancerous effects of the perchlorate used in Solid Rocket Fuel (see the article below for one example), so I don't think it will be very long before something alternative has to be designed.http://www.ewg.org/reports/rocketscience/If I had to guess, I'd give the current SRB's about ten more years before they'll have to be replaced because of that.So anyone in the rocket producing business might be wise to start contemplating alternatives fairly soon. At 2m lb thrust each with a 140 second burn time that's asking quite a lot, but some fairly large LH2/LOX boosters would produce no environmentally damaging effects. If they could be made easily re-usable, so much the better.Ross.
rsp1202 - 17/11/2005 3:43 PM"The decision has been made to use an air-start SSME, not the J-2. It offers greater performance, is available immediately."I stand corrected on the second-stage motor, but about being available immediately, has the SSME been tested in restart mode? Thought that was yet to be done. As for the rest, it's hard to disagree with a well-reasoned argument, especially the cost factors, other than by saying all the individual parts have yet to be tested together other than in computer sims. There are a myriad of new components that are still drawing-board sketches, such as solid's new roll motors, guidance package, etc. I believe in "trust, but verify." And give the first crew to ride a solid a cigar.
kraisee - 17/11/2005 1:28 PMRoss.PS - Avron, 4 SRB = lots of lift capacity Heh heh heh.
PMN1 - 19/11/2005 5:05 AMFrom what i've read, there were disagreemnets between the payload capacity of the orbitter NASA wanted and the payload capacity of the one the USAF wanted - would there be a case for two types of orbitters, a smaller in-line on for NASA and the larger historic side mounted on for the USAF but using as many common parts as possible?What would be the cost implications of this?
kraisee - 19/11/2005 1:30 PMQuotePMN1 - 19/11/2005 5:05 AMFrom what i've read, there were disagreemnets between the payload capacity of the orbitter NASA wanted and the payload capacity of the one the USAF wanted - would there be a case for two types of orbitters, a smaller in-line on for NASA and the larger historic side mounted on for the USAF but using as many common parts as possible?What would be the cost implications of this?Are you refering to the decision back in the 70's or alternatives over the current NASA/USAF disagreement?If you mean the 70's decision for NASA to make a Shuttle in close cooperation with the USAF, what happened then was entirely due to the very limited budget, and probably had to happen that way. Nixon was determined that the very last American Astronaut would fly during his Presidency - he wanted NASA closed down. By getting together with the USAF, NASA probably saved the entire program. It was unfortunate that it created the compromised launch system we now call Shuttle, but it was entirely necessary just to keep NASA alive. If you're alive, you can do stuff in the future to change your prospects. If you're dead, that's pretty-much it.
PMN1 - 19/11/2005 3:48 PMAhh I hadn't realised it was that serious, yes if your partially alive you can try something if you're dead thats it..
PMN1 - 19/11/2005 5:29 PMQuotePMN1 - 19/11/2005 3:48 PMAhh I hadn't realised it was that serious, yes if your partially alive you can try something if you're dead thats it..What had NASA done to piss Nixon off so much??
PMN1 - 20/11/2005 4:24 AMIf the main engines had been ET mounted from the start, would it have been possible to introduce recovery and re-use that was economic compared to just throwing them away along with the tank?
AndyMc - 19/11/2005 6:37 PMQuotePMN1 - 19/11/2005 5:29 PMQuotePMN1 - 19/11/2005 3:48 PMAhh I hadn't realised it was that serious, yes if your partially alive you can try something if you're dead thats it..What had NASA done to piss Nixon off so much??NASA was a creation of the Kennedy administration. Kennedy defeated Nixon in the 196? election and Nixon was known to bear a grudge or two. Plus there was a war to pay for.
darkenfast - 20/11/2005 2:07 PMA very nice summary, John. As I grew up watching the Space Program from Mercury on, I was always shocked when some Congress Critter would would come out thundering against "wasting all this money" in space when we could be spending it on welfare here. Of course, they don't say "welfare" now, they say "social programs", but the hostility against a program that revolves around the best and brightest is still there.
kraisee - 19/11/2005 1:30 PMAnd ultimately, a mega-sized Hubble would also be possible that way too!Ross.
darkenfast - 20/11/2005 1:07 PMA very nice summary, John. As I grew up watching the Space Program from Mercury on, I was always shocked when some Congress Critter would would come out thundering against "wasting all this money" in space when we could be spending it on welfare here. Of course, they don't say "welfare" now, they say "social programs", but the hostility against a program that revolves around the best and brightest is still there.