lad@eplrx7.UUCP (Lawrence A. Deleski) (09/20/88)
I was watching an ABC special program the other night titled, The Shuttle
and Beyond, or something like that. Anyway, one thing the announcer said
puzzled me.
She stated that NASA at this time does not have any heavy lift capacity
boosters, and that it would take ~1.2 Billion dollars to design and build
one.
This struck me as rather odd since the Saturn V booster to this date has
the heaviest lift capability of any booster built by anyone.
Now, I know that the Saturn V has been scrapped, but with such a capable
booster having already been designed and flown several times, wouldn't it
be easier to resurrect the Saturn booster and fly them again rather than
designing a new one?
Those statements came in reference to our ability to put a space station in
orbit. The USSR has a new booster, she stated, that has nearly the lift
capability of the Saturn V, but that the US did not have such a vehicle
anymore. Hence, Russia could have an orbiting space station well before
we would.
It would surely take forever to get a station into orbit using the payload
capacity of the currnet shuttle. We need a heavy lift booster, and Saturn
should get the nod.
Any opinions?
--
Lawrence A. Deleski | E.I. Dupont Co.
uunet!eplrx7!lad | Engineering Physics Lab
Cash-We-Serve 76127,104 | Wilmington, Delaware 19898
MABELL: (302) 695-9353 | Mail Stop: E357-302henry@utzoo.uucp (Henry Spencer) (09/21/88)
In article <677@eplrx7.UUCP> lad@eplrx7.UUCP (Lawrence A. Deleski) writes: >She stated that NASA at this time does not have any heavy lift capacity >boosters, and that it would take ~1.2 Billion dollars to design and build >one. >This struck me as rather odd since the Saturn V booster to this date has >the heaviest lift capability of any booster built by anyone. >Now, I know that the Saturn V has been scrapped, but with such a capable >booster having already been designed and flown several times, wouldn't it >be easier to resurrect the Saturn booster and fly them again rather than >designing a new one? Eugene, better hurry up with the revised frequently-asked-questions list! For those who can't wait, one of the things I sent in to Eugene to be added to the list was this: -------- Q. Could the Saturn V be revived as a heavylift booster? A. In principle, yes. In practice, there are many problems. Most of the specialized production tooling is gone. Some of the plans are gone. Some of the subcontractors are gone. Nobody remembers how to start an F-1 engine safely (!) (some of the details never got into the documentation). The launch facilities at the Cape have all been altered for the shuttle. It wouldn't be quite as hard as building a heavylift booster from scratch, but much of the work would have to be done over. -------- Incidentally, there is reason to believe that the heaviest version of Energia probably has greater lift capacity than the Saturn V had. -- NASA is into artificial | Henry Spencer at U of Toronto Zoology stupidity. - Jerry Pournelle | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
eder@ssc-vax.UUCP (Dani Eder) (09/22/88)
Note to Eugene Miya or whoever is collecting the frequently asked questions list: add this on to it.
Why not resurrect the Saturn V to give us a heavy lift capability?
Author's Qualification: 6 years of launch vehicle studies for Boeing.
Background:
Saturn V; Payload to Earth orbit = 260,000 lb.
Cost to develop (in 1988 dollars): $5 billion each for first and
second stages.
The main reason for not resurrecting the Saturn V booster is that
the first and second stage engines have been out of production for many years.
In order to restart making those engines, one would have to partly reverse
engineer the components from the half-dozen or so engines that have been
kept in clean storage (i.e. not the ones on display outdoors). This is
because some of the component maker have gone out of business, and for
others, the people who engineered and built the parts have retired. In
other words, the knowhow has partly evaporated.
The second reason for not resurrecting the Saturn V is that there
is no place to launch it. The Vehicle Assembly Building, ~rMobile Launch
Platforms, and Launch Pads have all been converted to the Space Shuttle.
It would take a lot of time and money to convert them back, and you
could no longer launch Shuttles. Building an addition to the VAB for
assembling Saturn V's and adding a third launch complex (39C) is possible,
in fact it was planned out to some extent under the assumption we
would go to Mars with Saturn V launchers, but would take money
(>1.5 billion in construction costs) and time.
The third reason for not resurrecting the Saturn V is that we
have an equivalent or better launch capability in the Space Shuttle,
should we wish to make use of it.
It is possible to make a variety of cargo launchers using the propulsion
elements of the Space Shuttle, but without carrying an orbiter. The
elements available are the Solid Rocket Boosters and the Space Shuttle
Main Engines. By varying the number of segments in the SRBs and the
number of SSMEs used, you can get different payloads. For reference,
the Space Shuttle uses two 4-segment SRBs and 3 SSMEs.
Examples: Payload Estimated Cost to Develop
2 3-segment SRBs + 1 SSME: 75,000 lb $1.2 billion
2 4-segment SRBs + 2 SSMEs: 140,000 lb $1.6 billion
2 4-segment SRBs + 3 SSMEs: 191,000 lb ?
2 5-segment SRBs + 4 SSMEs: 267,000 lb ?
Add for Advanced SRBs: about 12,000 lb $1 billion
Add for Block II SSMEs: about 10,000 lb per ?
(Pratt & Whitney new SSME
turbopumps, 15% higher thrust)
so: best 2x5 SRBS + 4 SSMEs: about 319,000 lb
Dani Eder, ZZ
--
Dani Eder / Boeing / Space Station Program / uw-beaver!ssc-vax!eder
(205)464-4150(w) (205)461-7801(h) 1075 Dockside Drive #905 Huntsville,
AL 35824 34 40 N latitude 86 40 W longitude +100m altitude, Earthdave@viper.Lynx.MN.Org (David Messer) (09/23/88)
In article <2240@ssc-vax.UUCP> eder@ssc-vax.UUCP (Dani Eder) writes: > >By varying the number of segments in the SRBs and the >number of SSMEs used, you can get different payloads. For reference, >the Space Shuttle uses two 4-segment SRBs and 3 SSMEs. How can you vary the number of segments in the SRBs? Wouldn't that change the combustion-chamber pressure rather drasticaly? -- If you can't convince | David Messer - (dave@Lynx.MN.Org) them, confuse them. | Lynx Data Systems -- Harry S Truman | | amdahl --!bungia!viper!dave | hpda / Copyright 1988 David Messer -- All Rights Reserved This work may be freely copied. Any restrictions on redistribution of this work are prohibited.
system@asuvax.UUCP (Marc Lesure) (09/23/88)
In article <1402@viper.Lynx.MN.Org>, dave@viper.Lynx.MN.Org (David Messer) writes: > In article <2240@ssc-vax.UUCP> eder@ssc-vax.UUCP (Dani Eder) writes: > > > >By varying the number of segments in the SRBs and the > >number of SSMEs used, you can get different payloads. For reference, > >the Space Shuttle uses two 4-segment SRBs and 3 SSMEs. > > How can you vary the number of segments in the SRBs? Wouldn't > that change the combustion-chamber pressure rather > drasticaly? Adding SRB's to the shuttle would also increase vibrational, aerodynamic, and g-force characteristics (among other factors). I can just see the tiles or wings getting "ripped-off" during launch. ----------------------------------------------------------------------- Marc Lesure / Arizona State University / Tempe, AZ "Between the world of men and make-believe, I can be found..." "False faces and meaningless chases, I travel alone..." "And where do you go when you come to the end of your dream?" UUCP: ...!ncar!noao!asuvax!lesure Internet/CSNET/ARPA: lesure@asuvax.asu.edu
deej@nvuxr.UUCP (David Lewis) (09/23/88)
In article <677@eplrx7.UUCP>, lad@eplrx7.UUCP (Lawrence A. Deleski) writes:
]
] I was watching an ABC special program the other night titled, The Shuttle
] and Beyond, or something like that. Anyway, one thing the announcer said
] puzzled me.
It was called "Beyond The Shuttle".
] She stated that NASA at this time does not have any heavy lift capacity
] boosters, and that it would take ~1.2 Billion dollars to design and build
] one.
]
] This struck me as rather odd since the Saturn V booster to this date has
] the heaviest lift capability of any booster built by anyone.
]
] Now, I know that the Saturn V has been scrapped, but with such a capable
] booster having already been designed and flown several times, wouldn't it
] be easier to resurrect the Saturn booster and fly them again rather than
] designing a new one?
]
I'm not certain about this, and anyone with hard facts is encouraged to
correct me if I'm wrong. But...
My understanding is that the plans and specs for the Saturn V have Gone
The Way Of All Good Things. Some are still sitting in files somewhere
(who was the prime contractor for the S-V?), but they are sadly
incomplete. There are no parts, no production facilities, no dies, and
incomplete plans to rebuild them. Building a Saturn V would require
going through virtually the entire design process over again.
How the mighty have fallen.
--
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
David G Lewis "somewhere i have never travelled..."
Bellcore 201-758-4099
Navesink Research and Engineering Center ...!bellcore!nvuxr!deejknudsen@ihlpl.ATT.COM (Knudsen) (09/24/88)
In article <2240@ssc-vax.UUCP>, eder@ssc-vax.UUCP (Dani Eder) writes: > It is possible to make a variety of cargo launchers using the propulsion > elements of the Space Shuttle, but without carrying an orbiter. The > elements available are the Solid Rocket Boosters and the Space Shuttle > Main Engines. By varying the number of segments in the SRBs and the > number of SSMEs used, you can get different payloads. For reference, [table of combinations dfeleted] Well, this is good thinking and the first time I've seen it spelled out this way. Use SSMEs as the base (literally and figuratively) for a new series of heavy launchers. One suggestion: Seems that what distinguishes the SSMEs from earlier liquid engines is their longevity -- designed for re-use, and test-fired for over 30 minutes. So any alternate plans for these engines should try to exploit this special feature. Staged rockets tend to burn for only a few minutes, while strap-on-boosted rockets (like the Shuttle) can burn longer. Are there any applications where a single engine that burns for over 20 minutes would be especially helpful? Like a Mars or deep-space probe (a big one), or something really huge into Clarke orbit? About the SRBs -- adding a segment makes it burn harder, not longer, for more thrust in the same time. I'd like a little more confidence in the nozzles and joints before we up the pressure on the one Shuttle component know to have failed disastrously. On the other hand, dropping one segment (3 segs) might give a very safe booster. BTW, to use up those pre-51L SRBs, strap them onto something, but not an Orbiter, please.
eder@ssc-vax.UUCP (Dani Eder) (09/25/88)
In article dave@viper.Lynx.MN.Org (David Messer) writes: > > How can you vary the number of segments in the SRBs? Wouldn't > that change the combustion-chamber pressure rather > drasticaly? > -- Yes, if that were the only variable you could play with. In tailoring SRBs, you can also change the throat area in the nozzle, which controls how fast combustion gases leave the motor, the shape of the grain (the chunk of solid propellant is called the grain, not the individual propellant grains) which affect how much surface area is exposed to burn, and the amount of burn-rate accelerators (iron oxide in the case of the Shuttle SRBs) mixed into the fuel. With all these parameters to play with, you can pretty much get what you want. For example, the Space Shuttle SRBs have a grain configuration that lowers the thrust during the time of peak aerodynamic pressure on the shuttle stack. Back in 1982 I worked on a study for Boeing for NASA on using all-SRB derived boosters. Thiokol was a subcontractor, and they supplied us with SRB versions ranging from 1 to 5 segments, compared to the 4 segments in the standard motor. -- Dani Eder / Boeing / Space Station Program / uw-beaver!ssc-vax!eder (205)464-4150(w) (205)461-7801(h) 1075 Dockside Drive #905 Huntsville, AL 35824 34 40 N latitude 86 40 W longitude +100m altitude, Earth
eder@ssc-vax.UUCP (Dani Eder) (09/25/88)
In article <359@asuvax.UUCP>, system@asuvax.UUCP (Marc Lesure) writes: > > Adding SRB's to the shuttle would also increase vibrational, aerodynamic, > and g-force characteristics (among other factors). I can just see the > tiles or wings getting "ripped-off" during launch. > Mr. Lesure has missed my original point, which is I was describing a heavy-lift cargo variant of the Shuttle which has no Orbiter (and thus no wings or tiles) The SSMEs are packaged in a recoverable pod which comes down on parachutes. My apologies if the original posting wasn't clear on this point. -- Dani Eder / Boeing / Space Station Program / uw-beaver!ssc-vax!eder (205)464-4150(w) (205)461-7801(h) 1075 Dockside Drive #905 Huntsville, AL 35824 34 40 N latitude 86 40 W longitude +100m altitude, Earth
tneff@dasys1.UUCP (Tom Neff) (09/25/88)
Since the SSMEs are designed for re-use as well as long burns, wasting them on Mars probes etc. would seem like a waste. An unmanned recoverable heavy launcher seems like the best way to go, since you would get them back after every use, and would be able to perform the reconditioning and igniter work right here on the ground where it's easiest. -- Tom Neff UUCP: ...!cmcl2!phri!dasys1!tneff "None of your toys CIS: 76556,2536 MCI: TNEFF will function..." GEnie: TOMNEFF BIX: t.neff (no kidding)
henry@utzoo.uucp (Henry Spencer) (09/25/88)
In article <6871@ihlpl.ATT.COM> knudsen@ihlpl.ATT.COM (Knudsen) writes: >Well, this is good thinking and the first time I've seen it spelled >out this way. Use SSMEs as the base (literally and figuratively) >for a new series of heavy launchers. > >One suggestion: Seems that what distinguishes the SSMEs from >earlier liquid engines is their longevity -- designed for re-use, >and test-fired for over 30 minutes. And their enormous price. Don't forget that. One significant problem in throwing SSMEs away is that they are awesomely expensive; this is why the current Shuttle-C plan is counting on using time-expired shuttle engines, not newly-built SSMEs. I'm not sure about the more recent Boeing studies, but almost everybody who has talked about serious use of SSMEs in expendables has also talked about trying to change the design to make it cheaper. >Are there any applications where a single engine that burns for >over 20 minutes would be especially helpful? Like a Mars or >deep-space probe (a big one), or something really huge >into Clarke orbit? Almost any in-space propulsion application is probably going to prefer using fewer engines but running them longer. Assuming that individual engines weigh the same either way, the results will be similar but the smaller number of engines will weigh less, and the lower acceleration will mean lower structural weights. There are limits to this, since for efficient trajectories one wants accelerations that are not dramatically lower than the local acceleration of gravity. There is also a complication in that your structure may need to stand higher accelerations earlier in its history, e.g. getting into orbit for the first time. (The shuttle is a particularly bad case since a shuttle payload has to be rated to take a 9G crash load *at right angles* to the usual thrust vector.) But on the whole lower thrusts are often desirable. -- NASA is into artificial | Henry Spencer at U of Toronto Zoology stupidity. - Jerry Pournelle | uunet!attcan!utzoo!henry henry@zoo.toronto.edu
knudsen@ihlpl.ATT.COM (Knudsen) (09/28/88)
In article <2248@ssc-vax.UUCP>, eder@ssc-vax.UUCP (Dani Eder) writes: > The SSMEs are packaged in a recoverable pod which comes down on > parachutes. Good idea. But don't the SSMEs go into orbit? Does their pod need both retro-rockets and an ablative heat shield to re-enter safely before deploying the chutes? Also, aren't the complex liquid engines more easily damaged by the splashdown and salt water corrosion while they're waiting to be fished out of the water? BTW, do the Russians use ablative shields on their Mir re-entries, or has something better been developed?
mike@mfgfoc.UUCP (Mike Thompson) (09/30/88)
From article <6936@ihlpl.ATT.COM>, by knudsen@ihlpl.ATT.COM (Knudsen): > In article <2248@ssc-vax.UUCP>, eder@ssc-vax.UUCP (Dani Eder) writes: >> The SSMEs are packaged in a recoverable pod which comes down on >> parachutes. > > Good idea. But don't the SSMEs go into orbit? > Does their pod need both retro-rockets and an ablative heat shield > to re-enter safely before deploying the chutes? > Also, aren't the complex liquid engines more easily damaged > by the splashdown and salt water corrosion while they're > waiting to be fished out of the water? Perhaps the pod the SSMEs would go in can be wrapped in ceramic tiles just like the shuttle is. It seems that the tiles would make a good (and cheap) replacement for an ablative head shield. The tiles may have to be thicker than the .5" to 4" ones on the shuttle. We could then aim the pod that contains the SSMEs towards a large desert on land (New Mexico???) for a soft landing by huge parachutes. This is assuming that sea water would damage an SSME. Just a few ideas I had. Mike Thompson --------------------------------------------------------------------------- Michael P. Thompson FOCUS Semiconductor Systems, Inc. net: (sun!daver!mfgfoc!mike) 570 Maude Court att: (408) 738-0600 ext 370 Sunnyvale, CA 94086 USA ---------------------------------------------------------------------------
henry@utzoo.uucp (Henry Spencer) (09/30/88)
In article <6936@ihlpl.ATT.COM> knudsen@ihlpl.ATT.COM (Knudsen) writes: >... don't the SSMEs go into orbit? >Does their pod need both retro-rockets and an ablative heat shield >to re-enter safely before deploying the chutes? >Also, aren't the complex liquid engines more easily damaged >by the splashdown and salt water corrosion while they're >waiting to be fished out of the water? Yes, recovering the engines is a headache. Depending on the design, they get either all the way into orbit or very nearly so. Retrorockets are no big deal, but heat shielding is a nuisance, and keeping them dry with an ocean splashdown is also a headache. This sort of thing is why the current Shuttle-C proposals don't envision engine recovery. (Admittedly, Shuttle-C is intended for a low launch rate and deliberately accepts higher per-launch costs for the sake of simpler development.) >BTW, do the Russians use ablative shields on their Mir re-entries, Yes. As they would probably say: "Why not? They work quite well." >or has something better been developed? Define "better". -- The meek can have the Earth; | Henry Spencer at U of Toronto Zoology the rest of us have other plans.|uunet!attcan!utzoo!henry henry@zoo.toronto.edu
craig@think.COM (Craig Stanfill) (10/03/88)
One of the problems associated with shuttle-derived expendables is the expense of the engines. Getting them back to earth seems to be a difficult problem. For example, developing independent re-entry pods for the engines seems a difficult undertaking. Another near-possibility would be to recover the engines via shuttle; after the shuttle's payload is deployed it would be (conceptually) possible to grab a few engines, stash them in the cargo bay, and bring them back down. However, I see several problems with this, and I doubt it is practical. 1. Part of the point of shuttle-derived expendables is to re-use the design of the aft part of the shuttle in the new vehicle. Clearly, this pod would be too large to fit in the cargo bay, so the engines would have to be removed from the thrust structure first. Unfortunatly, the engines are not designed to be jetisoned in-orbit, and making this possible is likely to require a major redesign of the thrust structures and connections. This loses a major part of the attractiveness of the redesign. 2 Matching orbits might be a problem. 3. It might considered too dangerous to put the engines into the cargo bay during re-entry. This is the closest I can come to a method for recovering the engines, but even here there are major problems. I doubt the re-use of the engines would justify the major re-engineering efforts.
knudsen@ihlpl.ATT.COM (Knudsen) (10/06/88)
One problem nobody's mentioned yet with respect to the idea of building a family of launchers out of old SSMEs: the plan was stated as using up SSMEs that had been used 10 or more times so they were no longer considered "man-rated." OK, so let's suppose I design this terrific Neptune probe whose launch requires 4 SSMEs in the 1st stage, 1 more in the 2nd and a 3rd one to send that probe off into deep space. That's 6 engines, all of which are officially deemed too unreliable any more to trust human life (or an Orbiter) to. If any ONE of those engines fails, there goes my nice big probe into the ocean. Do you expect me to be enthusiastic about the upcoming launch? OK, so losing the probe isn't as bad as losing an Orbiter plus the public effects of losing its crew, but somehow using officially untrustworthy engines for anything other than John Denver seems foolish. Especially if more than 3 are required.
eder@ssc-vax.UUCP (Dani Eder) (10/06/88)
In article <6936@ihlpl.ATT.COM>, knudsen@ihlpl.ATT.COM (Knudsen) writes: > In article <2248@ssc-vax.UUCP>, eder@ssc-vax.UUCP (Dani Eder) writes: > > The SSMEs are packaged in a recoverable pod which comes down on > > parachutes. > > Good idea. But don't the SSMEs go into orbit? > Does their pod need both retro-rockets and an ablative heat shield > to re-enter safely before deploying the chutes? > Also, aren't the complex liquid engines more easily damaged > by the splashdown and salt water corrosion while they're > waiting to be fished out of the water? > Yes, yes, and no, we would land on land, using airbags to cusion the last few feet. The recovery pod weights enough that winds don't significantly perterb the reentry. So a landing on land can be done within about a one mile cirle landing area. . . . . . . . . . . . . -- Dani Eder / Boeing / Space Station Program / uw-beaver!ssc-vax!eder (205)464-4150(w) (205)461-7801(h) 1075 Dockside Drive #905 Huntsville, AL 35824 34 40 N latitude 86 40 W longitude +100m altitude, Earth
khai@amara.uucp (S. Khai Mong) (10/07/88)
On recovering SSME's from heavy lift boosters: In article <2310@ssc-vax.UUCP> eder@ssc-vax.UUCP (Dani Eder) writes: > Yes, yes, and no, we would land on land, using airbags to cusion the last > few feet. The recovery pod weights enough that winds don't significantly > perterb the reentry. So a landing on land can be done within about a > one mile cirle landing area. Still, you would need a wider area for a safety margin? And where would that be if the launch were from KSC? I suppose that the Sahara would be a big enough target. Or somewhere in Australia. This is assuming that you do not wish to take the engines into full orbit. So would we take the engines into full orbit? -- Vitamin C deficiency is apauling +---------------------------- Don't blame me for what my fortune cookie says! Sao Khai Mong: Applied Dynamics, 3800 Stone School Road, Ann Arbor, Mi48108 (313) 973-1300 (uunet|umix)!amara!khai khai%amara.uucp@umix.cc.umich.edu