#21
|
|||
|
|||
Len wrote:
Yes, we considered the Sukhoi--but acquiring them is complicated. You can get a Chinese-made one at your local Wal-Mart. :-) Pat |
#22
|
|||
|
|||
In sci.space.history Peter Stickney wrote:
In article , Pat Flannery writes: 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. The same would hold true for Pegasus. ... Well, Pegasus has a lot more unmanned explosive solid rocket mass (19 tons). Considering the RASCAL is smaller and the manned first stage gives a more significant portion of the energy, the whole expendable should be about 3 tons, most of which is the non-explosive hybrid stage. (Ok, still wouldn't want to be hit by that.) And it's flying more predictably, outside the atmosphere to start with. The old Preston Carter pdf also says the release from the aircraft stage is at about 60 km height. If there's some performance margin, you can get a few tens of kilometers lateral distance from the launch site too, doesn't that help enough to get over the ocean for care-free release? I understand that the NF-104 rocket-augmented Starfighter was very hard to control when coming down from ~40 km (reason for SS1's shuttlecock), how is RASCAL going to solve these problems, if it's supposed to operate routinely? 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. Couldn't one design standard quick-to-configure spysat payloads, or is 75 kg so small that you have to have specialized ones because of instrument tradeoffs? Computers can anyway determine the needed trajectory (if/when it's possible with launch constraints) parameters in seconds. -- Pete Stickney A strong conviction that something must be done is the parent of many bad measures. -- Daniel Webster -- meiza: tmaja at cc hut fi |
#23
|
|||
|
|||
Peter Stickney wrote:
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.) I've seen lots of films of those being fired....they really do move out at a hell of a high velocity. 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. I've got a 105mm APFSDSLRP practice round; the practice round uses a front end made out of a low melting temperature alloy so that the front of the dart melts off after a few seconds of travel due to air friction heating it. The projectile is then aerodynamically unstable, and loses its velocity via tumbling. Careful there, Pat, them's Fightin' Words! I get the laser-powered flying car! I get the laser-powered flying car! 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) It took a _spectacular_ amount of paperwork, especially due to its classified nature. The GAO was ****ed off at the Lockheed Skunk Work's approach to paperwork and documentation on the F-117 project...which was basically to generate as little as possible, and burn it as soon as it wasn't absolutely necessary to retain- the Soviets couldn't steal it if it didn't exist. At the end of the design process they had all the jigs and materials needed to build the production aircraft, and almost no other surviving paperwork as to the reasons why exactly it was designed the way it was. The assembly line workers knew the tolerances they must meet... but not why those tolerances were necessary. And then came the B-2 ATB project...and a virtual army of Air Force pencil pushers descended on Northrop to make sure all the government's dollars were being well spent. The F-117 team had a total of 240 people on it between Lockheed and the Air Force personnel; over 2,000 Air Force personnel showed up at Northrop's Palmdale plant to make sure that everything was on the up-and-up with its design and costs... these 2,000 generated an average of over _1,000,000_ pages of paperwork _per day_ while working on the project, according to Ben Rich in his book "Skunk Works". Someone suggested that _all_ the paperwork should be made declassified, as no one was ever going to find the important stuff in that forest of wood pulp. Stamping "classified" on something simply attracted attention to it. So....was the program's security compromised? Well, that Sukhoi Su-25 Frogfoot looked a lot like the Northrop A-9; the design that lost to the Fairchild A-10... and so this little Russian aircraft design shouldn't come as much of a surprise, either. Comrade! Behold mighty M-67 LK-M stealth aircraft: http://www.ussr-airspace.com/catalog...8/12155757.jpg http://www.ussr-airspace.com/catalog...8/12155808.jpg http://www.ussr-airspace.com/catalog...8/12155821.jpg Is triumph of Russian aerodynamic genius! Is complete lie that is based on design found on page # 310,674,983 of paperwork found stuffed in trash bin at Northrop Corporation! Page was actually # 132,745,781- other page has design for aircraft's toilet paper dispenser on it... is still being studied carefully, as is signed off on by 347 people, and must therefore be very important to aircraft's design! Pat |
#24
|
|||
|
|||
In article ,
meiza writes: In sci.space.history Peter Stickney wrote: In article , Pat Flannery writes: 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. The same would hold true for Pegasus. ... Well, Pegasus has a lot more unmanned explosive solid rocket mass (19 tons). Considering the RASCAL is smaller and the manned first stage gives a more significant portion of the energy, the whole expendable should be about 3 tons, most of which is the non-explosive hybrid stage. (Ok, still wouldn't want to be hit by that.) And it's flying more predictably, outside the atmosphere to start with. Yoou're still going to have to track it, and the lauanch airplane, on the way up. What's really needed is an equally portable tracking and monitoring system. I woudn't be sirpriosed if somebody could put something together with an E-3 (AWACS) and a couple of hte EC-18 (ARIA) aircraft. It's a lot more feasible these days, since the airplanes can actually tell where they are with some certainty. The old Preston Carter pdf also says the release from the aircraft stage is at about 60 km height. If there's some performance margin, you can get a few tens of kilometers lateral distance from the launch site too, doesn't that help enough to get over the ocean for care-free release? Not necessarily. The concern isn't so much failure on release, as the rocket goes haring off on its own while under power. Ideally you'd like it to hit something soft, cheap, adn which won't due. I understand that the NF-104 rocket-augmented Starfighter was very hard to control when coming down from ~40 km (reason for SS1's shuttlecock), how is RASCAL going to solve these problems, if it's supposed to operate routinely? The F-104 configuration had some particulalry nasty high Angle of Attack behavior. A large part of its mass was also taken up by the spinning compressor/turbine rotor in the engine, which led to gyroscopic precession of the aircraft. (That's always there, but without any airflow over the aircraft to stabilize it, it becomes significant) The problem was gatting keeping the airplane entering nose first. With no air to stabilize it, it enters very nose high. I suspect that in the case of Yeager's last NF-104 flight, it was high enough to blank the tail. The precession will tend to make it enter sideways, IIRC. The stability reasons were one factor in Rutan developing the "Feather" or "Shuttlecock" mode for SS1. The other main factor is that he wanted as much drag early on as posssible, so that the reenteriing aerospacecraft wouldn't accelerate to a high Mach Number, and thus generate a lot of heat. 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. Couldn't one design standard quick-to-configure spysat payloads, or is 75 kg so small that you have to have specialized ones because of instrument tradeoffs? Computers can anyway determine the needed trajectory (if/when it's possible with launch constraints) parameters in seconds. As for payload size - it depends on what you want to do. I'd venture to say that it is rather small for a high resolution imaging system or an ELINT system, especially if you want to cover several bands of teh EM spectrum. You'd need a lot of specialized payloads, and you'd need to keep them around. One thing we've found is that long-term storage of satellites, and transporting them all over, isnt a good idea. The inital trajectory is easy enough to figure out, but factoring in weather conditions & such - especially for a quick reaction "one-pass-look" system like we are, at the moment, postulating, is a much more complicated problem. It doesnt' do any good if you go through a cras effort to launch you satellite, then have it not able to see the target on the first pass, for whatever reason. A mussed opportunity on the first shot couldn't be made up by the same satellite for something like 18 hours. If you're cramming sensors into a small, short-lived payload, you won't have much mass/volume available for power. -- Pete Stickney A strong conviction that something must be done is the parent of many bad measures. -- Daniel Webster -- Pete Stickney A strong conviction that something must be done is the parent of many bad measures. -- Daniel Webster |
#25
|
|||
|
|||
In article ,
Peter Stickney wrote: ...Considering the RASCAL is smaller and the manned first stage gives a more significant portion of the energy, the whole expendable should be about 3 tons, most of which is the non-explosive hybrid stage. (Ok, still wouldn't want to be hit by that.) And it's flying more predictably, outside the atmosphere to start with. Yoou're still going to have to track it, and the lauanch airplane, on the way up. That's a question of policy, not a law of nature. The US launch ranges traditionally insist on having continuous tracking data, but not everyone is so fussy, even in the big-launcher world. The H-II has only the most limited ground tracking, with flight control after it goes over the horizon relying mostly on relayed telemetry. Proton isn't tracked at all; the flight-termination system is entirely autonomous and there is *no* command uplink to the first three stages. Policies can be changed. -- "Think outside the box -- the box isn't our friend." | Henry Spencer -- George Herbert | |
#26
|
|||
|
|||
Mike Flugennock wrote:
Wasn't one of the Wrights' first thoughts, after privately building and flying their proof-of-concept vehicle, of what the Gummint might be able to use it for, and how much they'd pay? They tried to sew up every patent they could on heavier-than-air flight; we can thank those patents for forcing Glen Curtiss to use ailerons rather than wing warping on his aircraft (the Wrights fought that in court also) which made planes a lot easier to build, especially when metal construction came along. You can read up on the Wright/Curtiss legal battle he http://www.curtisswright.com/history/1909-1917.asp The Wrights were in it for a buck. Pat |
#27
|
|||
|
|||
|
#28
|
|||
|
|||
Pat Flannery wrote:
The F-117 team had a total of 240 people on it between Lockheed and the Air Force personnel; over 2,000 Air Force personnel showed up at Northrop's Palmdale plant to make sure that everything was on the up-and-up with its design and costs... these 2,000 generated an average of over _1,000,000_ pages of paperwork _per day_ while working on the project, according to Ben Rich in his book "Skunk Works". Ben Rich doesn't like supervision much, and tends to exaggerate. If find it hard to credit that any individual could create 500 pages a day. Someone suggested that _all_ the paperwork should be made declassified, as no one was ever going to find the important stuff in that forest of wood pulp. Stamping "classified" on something simply attracted attention to it. So....was the program's security compromised? Well, that Sukhoi Su-25 Frogfoot looked a lot like the Northrop A-9; the design that lost to the Fairchild A-10... and so this little Russian aircraft design shouldn't come as much of a surprise, either. Comrade! Behold mighty M-67 LK-M stealth aircraft: http://www.ussr-airspace.com/catalog...8/12155757.jpg http://www.ussr-airspace.com/catalog...8/12155808.jpg http://www.ussr-airspace.com/catalog...8/12155821.jpg Is triumph of Russian aerodynamic genius! Given the number of other design convergences, in aircraft as well as other fields. One shouldn't be surprised. Given that the site you cite is a drooling fanboy site which features a repainted Orion (http://www.ussr-airspace.com/catalog...ucts_id=18 56) and a repainted U2 (http://www.ussr-airspace.com/catalog...ucts_id=15 10) D. -- Touch-twice life. Eat. Drink. Laugh. -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL |
#30
|
|||
|
|||
Pat Flannery wrote:
snipped discussion of material that shows only *current* (I.E. post 1990's) aircraft designs... With no evidence that the designs were contemporary. Pat; Take anything claiming the Soviets had such-andsuch with a massive grain a salt. It's a growing cottage industry to produce massive glowing accounts of Great Soviet Terror Machines that were never built... And sell them to a gullible and drooling public. The same is true of many WWII era German designs. To read the websites and the books one could be forgiven for believing the Germans came within a few turns of a wrench on a WunderAircraft of winning WWII. We both know that's not true, and why. D. -- Touch-twice life. Eat. Drink. Laugh. -Resolved: To be more temperate in my postings. Oct 5th, 2004 JDL |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Rutan's hints of future directions in Discovery documentary: Tier Two and beyond | Neil Halelamien | Policy | 0 | October 13th 04 02:51 AM |
That wascally RASCAL | Allen Thomson | Policy | 3 | September 25th 04 10:35 PM |
X-Prize: Scaled considering passengers on second flight | Andrew Gray | Policy | 6 | August 8th 04 06:35 PM |
Rutans White Knight as IR observatory | Carsten Nielsen | Technology | 7 | February 29th 04 03:13 AM |
Rascal? | Richard Stewart | Technology | 10 | October 7th 03 06:40 PM |