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In sci.space.history Pat Flannery wrote:
If it succeeds, RASCAL would give the military NRO and NSA a unique capability in regards to space access; such a vehicle would be capable of launching a large number of small satellites onto orbital paths that would take them over "hotspots" on their first orbit, allowing SIGINT ... The mission launch rate of once per 24 hours means that a small number of these aircraft/booster combos could put up stored satellites or interceptors every few hours in an emergency. Although such a craft could have scientific or commercial uses, the funding by DARPA suggests that its use is intended to be primarily military in nature. Pat Wasn't something similar the original motivation behind delta clipper too? A cheap way to launch the "brilliant pebbles", a huge amount of small satellites that could intercept soviet ballistic missiles... Well, this RASCAL thingy maybe wouldn't be _so_ cheap as a true rlv, but sounds like a more doable compromise. It might have a fast turnaround, since it doesn't go into orbit, and the expendable parts can be manufactured for storage with reasonable cost. Don't know about the aircraft part maintenance then, the flight profile doesn't seem easy on the engines. Why are the second and third stages so cheap? 750 000$ per flight, it puts 75 kg to 500 km. That makes RASCAL about 10 000 $ / kg. Minuteman is 6 million bucks and Taurus is 20 million. Taurus only launches 1300 kg to 180 km, making it about twice as pricey as RASCAL? With the aircraft you get rid of the fairing and don't have to deal with drag or aerodynamic stabilization in the expendable part, but does that help a lot? And of course some deltavee too. Do you need hundreds of launches before all this makes sense? Well, that can only be seen when it's been built. There's a pic of a windtunnel test article at space launch corp's homepage: http://www.spacelaunch.com/news_2004_002.asp Very basic layout, like a concorde on steroids Earlier concepts had nose intake and less engines, I remember. Seems they have scaled up. I had some trade study pdf laying around but can't find it from the internet now... The company also has a project where an f-4 phantom carries some launch vehicle. But Scaled Composites is doing very well, plastic aircraft flying mach 3... welcome to the 21st century! -- tmaja ät cc hut fi |
#12
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Damon Hill wrote:
What's this four-engine souped-up hotrod going to look like? Could a MiG-25 be modified for similar performance? A Lockheed M-12 probably could have, and would have had the launch pylon for the booster built in; you'd have to add a RCS system for control at full altitude though. I'm a little concerned about SpaceShipOne, RASCAL, and the Ansari prize though one gets the feeling that part of the reason the White Knight/SpaceShipOne combo was built was as a proof of concept vehicle for RASCAL, and that IMHO violates the spirit of the Ansari prize and no government funding...if you know that you have a government contract pretty well sewn up if something you are building works, is what you are then doing really private? On the flipside, I am giving myself a Pat on the back for having seen this coming; from a posting to sci.space.history on April 21st, 2003: "Alan Erskine wrote: From the article on AW&ST's site, there's a sponsor so it's not just Rutan paying for this out of his own pocket. That in itself bodes well for the future. The name "White Knight" is interesting; as it reminded me of the Air Force's "Black Horse" program (see the carrier is the knight; the thing under it the horse)....which makes one wonder: is there a "Black Knight" out there somewhere? Pat" Anyone else suspect that RASCAL's carrier aircraft is going to be named "Black Knight"? And be represented by a drawing of a Black Knight on horseback riding across a starry sky, with the booster rocket mounted under his arm like a lance? Pat |
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Pat Flannery wrote in message ...
Len wrote: As leader for the first stage on the Coleman RASCAL Phase I effort, I seriously considered the MiG-25. In the existing aircraft category, we finally ended up with the F-14 as being most suitable for RASCAL. The spacecraft booster snuggles up between the two engine ducts, right? Yes, the space between the engnes is about 1.5 to 1.6 meters by about 1.6 m aft vertically, some of which has to allow for ground clearance. Length between the nose gear and ventrals is more the problem, but we have some tricks to deal with this constraint. With centerline carriage, we can carry as much as 9 tonnes-- much more than would be possible with the F-15 and wing carriage. We believed--and continue to believe--that a new aircraft would bust the DARPA RASCAL budget, which it already has. Our post-RASCAL effort suggests that a rocket-powered F-14A with readily available TF-30 engines could exceed RASCAL payload and cost goals with very little modification other than addding the rocket system. Where's the rocket supposed to go- in a fairing between the two engine nozzles, or duel units on the underduct areas normally used for the four Phoenix missiles? Pat Two rocket concepts: One requires new, small, high chamber pressure engines with relatively low expansion ratio. Four of these (30-cm nozzle diameter) engines fit rather unobtrusively between the engines behind the upper-stage package. Alternatively, one Aerojet/Kuznetsov NK-31/39 engine fits between the TF-30's as a third engine. One difficulty is getting enough LOX aft for balance. The RA-5 Vigilante also looked interesting, but none are available. There's lots of F-14As available. Best regards, Len (Cormier) PanAero, Inc. (change x to len) http://www.tour2space.com |
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Why are the second and third stages so cheap? 750 000$ per flight, it
puts 75 kg to 500 km. That makes RASCAL about 10 000 $ / kg. Does anyone know what flight rate (and other assumptions if known/relevant) that is based on? http://www.spacetether.com/rascal.html says 10/year. I'm kind of assuming the cost will end up higher (as Pegasus did compared with the cost numbers from the early stages of the program), especially at that flight rate. |
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IMHO violates the spirit of the Ansari prize and no government
funding...if you know that you have a government contract pretty well sewn up if something you are building works, is what you are then doing really private? If government contractors were, as a general rule, prepared to fund a development program on their own dime, and only charge the government anything if it works, it would, well it would be a pretty dramatic change from the status quo. |
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meiza wrote:
There's a pic of a windtunnel test article at space launch corp's homepage: http://www.spacelaunch.com/news_2004_002.asp Very basic layout, like a concorde on steroids Actually a lot more like the original Tu-144 Soviet SST design on steroids... that had all the jet engines in a single housing. It's not exactly underpowered looking, is it? Pat |
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Len wrote:
The RA-5 Vigilante also looked interesting, but none are available. There's lots of F-14As available. Yeah, the center tubuler bomb bay would have been perfect for putting the rocket and it's fuel in. With an expendable rocket you could have jettisoned the motor assembly, then slid the orbital booster out after it. Did you ever see the proposed interceptor varint that carried a third engine in there?: http://www.vectorsite.net/ava56.jpg Did you consider the Sukhoi Flanker? Its underbelly is also of the right shape, and it already is designed to carry the big "Sunburn" missile down the http://home19.inet.tele.dk/airwing/a...oskit-su33.jpg Pat |
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"Pat Flannery" wrote in message
... I'm a little concerned about SpaceShipOne, RASCAL, and the Ansari prize though one gets the feeling that part of the reason the White Knight/SpaceShipOne combo was built was as a proof of concept vehicle for RASCAL, and that IMHO violates the spirit of the Ansari prize and no government funding...if you know that you have a government contract pretty well sewn up if something you are building works, is what you are then doing really private? If you've seen some of the recent documentaries on SS1, you'd see that Rutan had been working on the concept for SS1 for such a long time that it is highly unlikely that RASCAL influenced the design of Wight Knight much. In particular, things like the pressurized cabin being structurally identical to SS1 (to save cost) seems to have more influence over the design of White Knight. NASA's B-52 has dropped a seemingly endless number of aircraft and rockets, so why can't Rutan reuse White Knight in the same way? Once an aircraft is designed and built, it seems silly to charge the government to design and build another aircraft with essentially the same specifications. Jeff -- Remove icky phrase from email address to get a valid address. |
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Pat Flannery wrote in message ...
Len wrote: The RA-5 Vigilante also looked interesting, but none are available. There's lots of F-14As available. Yeah, the center tubuler bomb bay would have been perfect for putting the rocket and it's fuel in. With an expendable rocket you could have jettisoned the motor assembly, then slid the orbital booster out after it. Did you ever see the proposed interceptor varint that carried a third engine in there?: http://www.vectorsite.net/ava56.jpg Did you consider the Sukhoi Flanker? Its underbelly is also of the right shape, and it already is designed to carry the big "Sunburn" missile down the http://home19.inet.tele.dk/airwing/a...oskit-su33.jpg Pat Yes, we considered the Sukhoi--but acquiring them is complicated. And, to meet DARPA's technology desirements, we would have had to make just as many modifications as we would have with the F-14D. Without a requirement to use MIPCC and zoom climb, adding a rocket system to the F-14A works just fine. There was a time when technolgy got short-changed. But for the past four decades, innovative, conceptual system design has been short-changed. One would think that high-payoff, low-risk systems that are innovative without using risky technology would be in great demand. However, no one in government seems to ask for that type of system. Not since a hush-hush group with only five government staffers produced the first recon satellites, the U-2, the A-11/12, etc., has there been a group dedicated to low-risk, high-payoff systems. Len |
#20
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In article ,
Pat Flannery writes: Peter Stickney wrote: the need to keep track of it on the way up, and have it fall somewhere other than, say, a Junior Jugh School in New Jersey if things go wrong They aren't going to live that down for a while, are they? Could have been worse...could have hit a ski-lift in the Italian Alps... The part that they didn't tell you about that one is that the Armee de l'Air has accounted for at least 3 tramways in the past 20 years. I don't know what the German record is. A coupe of apropos tales, though, with happy endings. Bill Stealy, the guy who launched MicroProse with Sid Meier, was in the NY Air National Guard. As he put it, he spent his military carrer bombing and strafing New Jersey - adn couldn't have done a very good job, 'cause its still there. Story the Second:L When Tank Boy, my youngets brother, was going through the Armor School at Ft. Knox, one of the Bright Young Recruits during Gunnery Practice got his switchology mixed up, and was firing Sabot (APFSDS - Armor Piercing Fin Stabilized Discarding Sabot) rounds using the HEAT (High Explosive Anti-Tank) settings in the Fire Control System. Now Sabot rounds move out at about a mile/second - they've got, needless to say, a flat trajectory. (And it's kinda eerie to observe a tank firing from 100 meters away, and seeing the round impact onthe target before the noise of teh firing reaches you.) HEAT desn't like to travel fast - a fast-moxing shell doesn't give the penetrating jet of the shaped charge in teh shell time to form - so it bloop out at a mere 2000 ft/sec or so. The rounds weere scored as clean misses - especially when a Little Old Lady outside of Louisvile called the post to see if the Army could come and pick up the 5 Lawn Darts that showed up in here back yard. have made that inherent flexibility moot. It's going to use _Soundless Rocket Engines_?! Oh, excuse me...I thought you wrote "Mook" for a second there. ;-) Careful there, Pat, them's Fightin' Words! Is there any reason to believe that those artificial requirements would be modified or lifted for Rascal? I rather doubt it, myself. In times of crisis, the launch restrictions would be put aside, as long as the booster stages came down over open ocean; it would be a lot easier (and cheaper) to keep some of these things loaded and ready to go than a fleet of Lockheed Tristars or B-52's, like Pegasus uses. Considering the price that Rutan built White Knight/SpaceShipOne at, he probably will be able to turn RASCAL out at a bargain basement price...if only the bureaucracy will leave him alone- and not drown him in paperwork, like the B-2 Stealth Bomber project was. The same would hold true for Pegasus. The gating itemis getting the proper payload selected, figuring out just what trajectory you want to use, and getting the payload and the booster mated and ready to go. That's a People Thing, and it's hard to reduce it.Oh, and there was plenty of paperwork on the B-2. You can't go ordering all that stuff and not generate paperwork. (Unless you're ordering by Interocitor, from Exeter Enterprises) If I were of a Nasty adn Suspicious Mind, I'd say that the B-2 required more than the usual paperwork - it takes a lot of overhead to build and maintain the necessary blinds, covers, and cut-outs. (Not that I'd know anything about that) -- Pete Stickney A strong conviction that something must be done is the parent of many bad measures. -- Daniel Webster |
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