Space shuttle for space tourism and first stage of a TSTO.
in [Physics]
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From: Jorge R. Frank on 14 Jan 2010 19:27 Jeff Findley wrote: > "Androcles" <Headmaster(a)Hogwarts.physics_r> wrote in message > news:fMp3n.6$qF1.3(a)newsfe11.ams2... >> "Derek Lyons" <fairwater(a)gmail.com> wrote in message >> news:4b502501.43877375(a)news.supernews.com... >>> Robert Clark <rgregoryclark(a)yahoo.com> wrote: >>> >>>> The ET tank is larger than the shuttle orbiter. My proposal would be >>>> to fit a much smaller tank, both in dimensions and mass, inside the >>>> payload bay. >>> Which gains you about 10 seconds, at best, of SSME burn time. >>> >>> D. >>> -- >>> Touch-twice life. Eat. Drink. Laugh. >>> >>> http://derekl1963.livejournal.com/ >>> >>> -Resolved: To be more temperate in my postings. >>> Oct 5th, 2004 JDL >> Hmm... enough to send a LEM and a command module >> out of Earth orbit and on their way to the Moon... and the >> CM back again. >> -- Laugh now, eat later. > > Absolutely wrong. > > Look at the size of the third stage of the Saturn V which performed the TLI > burn for the Apollo lunar missions. Here's a hint, it's far too large to > fit in the shuttle payload bay. > > If you don't believe this, do the math and post the result here. Several > readers of this group are qualified to check your math. Just for reference (and Androcles won't see this since he killfiled me): CSM/LM mass = mf = 100000 lbm Maximum shuttle payload mass = mp = 60000 lbm (we'll be kind and assume the stage and engine have zero mass) Gravitational constant = g = 32.2 fps^2 TLI delta-V = dv = 10000 fps Rocket equation: dv = Isp*g*ln((mf + mp)/mf) Solve for required Isp: Isp = dv/(g*ln((mf + mp)/mf) = 10000/(32.2*ln((100000+60000)/100000) = 660 s Far higher than is possible with LOX/kero, or even LOX/LH2, even with a massless engine and stage structure. Or as I put it, more concisely, the first time: Wrong.
From: Pat Flannery on 14 Jan 2010 22:22 Derek Lyons wrote: > To which the answer is the same: A fuel tank in the cargo bay gains > you 10 seconds, at best, of NK-33 burn time. Extra boosters over the wings, and conversion into a biplane!: http://www.airalex.com/files/ARMAGEDDON_SHUTTLE.JPG Pat
From: Pat Flannery on 15 Jan 2010 00:06 Jorge R. Frank wrote: > > Far higher than is possible with LOX/kero, or even LOX/LH2, even with a > massless engine and stage structure. How about we use mono-hydrazine, like on the Vulture? Pat
From: Me on 14 Jan 2010 22:22 On Jan 14, 5:22 pm, Robert Clark <rgregorycl...(a)yahoo.com> wrote: > > Remember a large mass of propellant carried on the *inside* is the > usual way rockets operate. Think of it this way: which would require > greater mass and complexity of structural strengthening members, > > the S-IC Saturn V first stage carrying the 5,000,000 lbs. of > propellant inside, as it actually did, or a huge outside tank hanging > off attachments points containing, say, 8,000,000 lbs, with just a big > empty space in the rocket between the engines and the second stage? Wrong, Not a valid comparison. Just shows that Clark doesn't know squat about what he is saying. The tank inside the orbit is not a structure component of the vehicle like the tank of a Saturn stage. The tank on the inside of the orbiter would have suspended within the orbiter just like the payloads are. Or to put in in words that Clark can understand, the tank would have to hang in the inside of payload bay. This make the tank heavier since it will need to have attach points like the ET and the payload bay would have beefed up. But as it has been stated here, on BAUT forum and SDC that this is not feasible nor is the rest of the idea not workable. So Clark so how many times and by how many people do you have be told that you ideas won't work? You must be an f'ing idiot to think you are right and everyone else is wrong. That is a sign of mental illness. How did you did get a degree and who did you pay off to let you become a math instructor? The school that employs you should have its accredition taken away. You are completely clueless when it becomes to engineering. Just stick to math theory since you have shown that you can't do math applications.
From: Me on 14 Jan 2010 22:31
On Jan 14, 4:46 pm, Robert Clark <rgregorycl...(a)yahoo.com> wrote: > It will require strengthening of the orbiter midfuselage, but I'm > arguing the extra structural mass would be less than the structural > mass already needed on the shuttle to hold the 500,000 kg or so of > propellant remaining in the ET after SRB sep. > You have no basis for your argument. The structure for holding the ET and SSME's is limited to the aft fuselage and it is account for in the existing orbit. The mods to orbiter midfuselage would be over larger volume and would affect the midfuselage attachment to the foward and aft fuselage and the wings. Also the already marginal landing gear and attachments would have be beefed up. Since the orbiter is dry mass is heavier or even in an abort scenario with some propellant left onboard the wings would need to be bigger. And then the hydraulics would need to be beefed up for the bigger wing and now the orbiter is even still heavier and now because ............ and so on and so on. But Clark still doesn't get it because he is not right in the head. |