david@beowulf.JPL.NASA.GOV (David Smyth) (10/11/88)
In article <1574@nunki.usc.edu> birenboi@sal6.usc.edu (Aaron Birenboim) writes: > >To say that the Soviet shuttle has no engines, however, is a misnomer. >THE SOVIET SHUTTLE HAS JET ENGINES. The soviet shuttle is actually a >full fledged PLANE. They have flown it around, and it has the ability >to take off from the ground, as a plane does! No more talk about the >soviets copying us. They used our exterior design idea, but made >MANY, MANY improvements to it. By using Jet engines, re-entry is >much safer and easier, because they can make many passes at a landing, >and don't need so many computers calculating an optimum flight trajectory. >They can probably fly the thing on total manual control, should >the computers die. By removing the bulky rocked engines, they also >have much more room for payload, in addition to the heavier load capacity >of the Energia system. I sincerely doubt that this is true. 1) Why would they want to fly the thing around like an airplane? This would require lotsa stuff completely unnnecesary for spaceflight: landing gear retractors, juet fuel tanks, all the junk to control the jet engines, ... 2) How fast do you thin the shuttle needs to go to get enough lift to go UP? Right now, the shuttle decends at about 100 feet per second throughout the re-entry: The thing does NOT fly, it drops like a brick. The wings just increase the manoeverability. 3) The Shuttle is such a bizarre handling aircraft that pilots tend to put it into PIO (Pilot Induced Oscillation). The center of pitch is several airframe lengths in front of the vehicle: when you pull back on the stick, the craft "feels" like it begins to sink quicker, when you push forward on the stick, it "feels" like it starts to go up! This is why it is NOT landed by pilots, but by the auto-land system. I watched the pilots try to land it on the Rockwell simulator, and I NEVER saw anybody do it: they ALWAYS crashed. The first landing on the runway at Edwards by the Enterprise, in front of all the political luminaries, was almost a disaster: they started that approach with the pilots on the sticks, and the gound controllers had to shut them off because they were approaching to structural limits of the airframe! The autoland system greased it on that time, and has hit the numbers every time since. The pilots DO NOT land the shuttle! I do not believe the Russians could land theirs manually either. The handling of both vehicles will be similar. 4) I doubt that jet engines poweful enough to get that turkey flying would weigh less than the SSMEs. Also, they do NOT have air intakes exposed, so any jet engines must be retractable: think for a moment how much weight and bulk THAT stuff would add to the soviet shuttle. Conclusion: I think we will find that the soviet shuttle has only OMS and RCS rockets, no other form of propulsion. That does make it simpler. And, I'll bet a donut that it will fly with IBM 370s in the racks, executing HAL/S software, just like ours. JUST like ours.
birenboi@sal18.usc.edu (Aaron Birenboim) (10/12/88)
In article <3020@jpl-devvax.JPL.NASA.GOV> david@beowulf.JPL.NASA.GOV (David Smyth) writes: >In article <1574@nunki.usc.edu> birenboi@sal6.usc.edu (Aaron Birenboim) writes: >> >>To say that the Soviet shuttle has no engines, however, is a misnomer. >>THE SOVIET SHUTTLE HAS JET ENGINES. The soviet shuttle is actually a >>full fledged PLANE. > >I sincerely doubt that this is true. > >1) Why would they want to fly the thing around like an airplane? This would >require lotsa stuff completely unnnecesary for spaceflight: landing gear >retractors, juet fuel tanks, all the junk to control the jet engines, ... The shuttle already has Flight control hardware, and a lot of hardware for rocket engines. I am but a student, but I think that whatever hardware that is necessary for the shuttle's rockets is larger that whatever jet engine is needed to power the Shuttlesky. Unfortunately, I cannot quote documents other than word of mouth of an ex director of JPL Deep Space Network. What have you seen that shows no Air intake? One photo which may have been re-touched is inconclusive. Who knows, they may even have covers for the air intake durring launch. > >3) The Shuttle is such a bizarre handling aircraft that pilots tend to >put it into PIO (Pilot Induced Oscillation). The center of pitch is >several airframe lengths in front of the vehicle... Can this be said of Shuttlesky also, without much knowledge of their design details? Does anybody have some estimates of the mass of Shuttlesky? If Shuttlesky can "fly" it would handle much better, although the shape of Shuttlesky may raise some doubt. >4) I doubt that jet engines poweful enough to get that turkey flying >would weigh less than the SSMEs. Do people who have worked with these systems think this is a valid accessment? >Conclusion: I think we will find that the soviet shuttle has only >OMS and RCS rockets, no other form of propulsion. That does make it >simpler. And, I'll bet a donut that it will fly with IBM 370s in >the racks, executing HAL/S software, just like ours. JUST like >ours. They STARTED development quite a while after us. I expect that their computers, if nothing else, would be ahead of ours. Is there anybody else who has heard of Jets on the Shuttlesky? (flames welcome) Aaron "The Lumberjack" Birenboim|"In the begining, the Universe was created... | This made a lot of people angry, and was GO TROJANS!! | widely reguarded as a bad move." birenboi@castor.usc.edu | -Douglass Adams _The Guide_
laurel@super.ORG (Our Friends Up the Way) (10/12/88)
In article <1574@nunki.usc.edu> birenboi@sal6.usc.edu (Aaron Birenboim) writes: >THE SOVIET SHUTTLE HAS JET ENGINES. The soviet shuttle is actually a >full fledged PLANE. They have flown it around, and it has the ability >to take off from the ground, as a plane does! No more talk about the >soviets copying us. They used our exterior design idea, but made >MANY, MANY improvements to it. Rubbish! I have seen the Soviet Space Shuttle, and it is almost identical to ours. In fact, most Americans would not be able to tell the difference between it and ours (except for the CCCP marking on the left wing). The most obvious difference I noticed was that the SRB's are much shorter. Other than that, its' a genuine example of technology transfer. First flight is scheduled for early December; delayed probably by a need to redesign the O rings.
jp@linus.UUCP (Jeffrey Picciotto) (10/12/88)
David Smyth writes: >2) How fast do you thin the shuttle needs to go to get enough lift to >go UP? Right now, the shuttle decends at about 100 feet per second >throughout the re-entry: The thing does NOT fly, it drops like a brick. >The wings just increase the manoeverability. Is this really true? How fast is it descending when it touches down? Assuming a reasonably slow rate of descent, doesn't this show that the shuttle could fly if it had useful and sufficiently powerful engines available? Just curious, --jeff {*}!linus!jp jpicc@mitre-bedford.arpa
petej@phred.UUCP (Pete Jarvis) (10/12/88)
>push forward on the stick, it "feels" like it starts to go up! This is >why it is NOT landed by pilots, but by the auto-land system. I watched >the pilots try to land it on the Rockwell simulator, and I NEVER saw >anybody do it: they ALWAYS crashed. The first landing on the runway >at Edwards by the Enterprise, in front of all the political luminaries, >was almost a disaster: they started that approach with the pilots >on the sticks, and the gound controllers had to shut them off because >they were approaching to structural limits of the airframe! The autoland >system greased it on that time, and has hit the numbers every time since. >The pilots DO NOT land the shuttle! I do not believe the Russians > Everything I have ever heard about Shuttle landing capability has said that the Shuttle Auto-land avionics software does most of flying/gliding for the vehicle with the pilots taking over at various intervals. However, on final approach, I heard the Auto-land system has NOT been used because they are unsure about the results and until they can test it more thoroughly, will not be used. The pilots, I hear, take over doing the "S" turns and on down to the landing. The pilots at the very least have stick control on short final. I saw a Shuttle taped special once that said the commander, (I forget who and what Shuttle it was), "was going to try to hit the numbers". He greased it right on the numbers. The Auto-land system would not have been able to do that except by luck. Peter Jarvis..........Physio-Control - Redmond, WA.
chuck@calvin.EE.CORNELL.EDU (Chuck Swenson) (10/12/88)
(Aaron Birenboim) writes: > Is there anybody else who has heard of Jets on the Shuttlesky? It seems I heard they had jets on it for testing only and they had been removed for flight. They did not use a 747 to haul it up for atmospheric testing and landings but actually did runway takeoff. I think this came from Aviation Week a couple months ago, but then I have a poor memory and it might all be fiction. Charles Swenson, School of Elect. Eng., Upson Hall Cornell University, Ithaca, NY 14853 ARPA: chuck@calvin.ee.cornell.edu SPAN: STAR::"chuck@calvin.ee.cornell.edu"
sw@whuts.UUCP (WARMINK) (10/12/88)
In article <40869@linus.UUCP>, jp@linus.UUCP (Jeffrey Picciotto) writes: > David Smyth writes: > >2) How fast do you thin the shuttle needs to go to get enough lift to > >go UP? Right now, the shuttle decends at about 100 feet per second > >throughout the re-entry: The thing does NOT fly, it drops like a brick. > >The wings just increase the manoeverability. > > Is this really true? How fast is it descending when it touches down? > Assuming a reasonably slow rate of descent, doesn't this show that the > shuttle could fly if it had useful and sufficiently powerful engines > available? > With a lift to drag ratio of approximately 4:1, it can be seen that for level flight the thrust of the engine(s) has to be at least 25% of the Shuttle's weight. Speed is not the only factor in determining rate of climb - angle of attack is too. There is a tradeoff between low-speed, high angle of attack and high-speed, low angle of attack flight, the optimum rate of climb is usually somewhere in between. The best gliding angle is also given by the L/D ratio (atan(D/L)), but in order to land with zero vertical velocity the actual glideslope is steeper, and the excess energy is used to allow for an increase of angle of attack in order to reduce the final rate of descent to nearly zero. So, I suppose the answer is that anything with any lift at all will fly, given enough thrust.... -- ------------------------------------------------------------------------------ Xlb lbtvist dufyew iyr qglr rgua alta? | Stuart Warmink, NAPC (Qwkk sibw, Hun lbs Jwbbt!) | <att!>whuts!sw Whippany NJ USA -----------> My opinions are not necessarily those of my employer <-----------
kluksdah@enuxha.UUCP (Norman C. Kluksdahl) (10/13/88)
In article <709@calvin.EE.CORNELL.EDU>, chuck@calvin.EE.CORNELL.EDU (Chuck Swenson) writes: > stuff deleted > It seems I heard they had jets on it for testing only and they > had been removed for flight. They did not use a 747 to haul it up for > atmospheric testing and landings but actually did runway takeoff. I > think this came from Aviation Week a couple months ago, but then I > have a poor memory and it might all be fiction. > One of the first photographs of the soviet shuttle was taken by a recon satellite, after the Bear carrier plane ended up stuck on the side of the runway after missing a taxiway (apparently). Speculation at that point was that the Soviet shuttle would be tested in much the same manner as the US shuttle--i.e. air launching from a carrier plane. (this was a while ago, BTW. I think it was in AvWeek, but i'm not sure.) N. Kluksdahl standard disclaimer implied.
stuart@speedy.cs.wisc.edu (Stuart Friedberg) (10/13/88)
Unfortunately, this posting doesn't include the text I wish to respond to, but the essence was "I have seen the Soviet shuttle; it's just like ours, they used (stole) our design; the SRB's are just a little shorter, they're probably delaying launch to fix the O-rings." That is nonsense. No matter how much the reentry body looks the same externally, it's not our design. The Soviet shuttle doesn't have SRB's, and it doesn't have O-rings. The boosters are liquid-fueled, unlike the NASA *Solid* Rocket Boosters. They are not assembled from pre-fabricated sections, with field joints requiring O-rings. The Soviet shuttle is an external payload on an existing Soviet heavy launcher. The *liquid fuel* boosters *without O-rings* belong to the launcher. The Soviet shuttle does not have anything at all like the NASA shuttle's SSME (Space Shuttle Main Engines).
steve@eos.UUCP (Steve Philipson) (10/13/88)
In article <3020@jpl-devvax.JPL.NASA.GOV> david@beowulf.JPL.NASA.GOV (David Smyth) writes: >In article <1574@nunki.usc.edu> birenboi@sal6.usc.edu (Aaron Birenboim) writes: >> >>To say that the Soviet shuttle has no engines, however, is a misnomer. >>THE SOVIET SHUTTLE HAS JET ENGINES. The soviet shuttle is actually a >>full fledged PLANE. They have flown it around, and it has the ability >>to take off from the ground, as a plane does! No more talk about the >I sincerely doubt that this is true. I haven't been reading this group very long, but still I am amazed at the amount of noise, mis-information, and uninformed speculation here. The sincer doubters should try reading Aviation Week once in a while. Many of the issues bludgeoned to death in this group are clearly explained in "Av Leak". Some time ago, Av Week ran a few short articles on the Soviet "shuttle". It was fitted with jet engines for atmospheric test flights. I think (not sure) that it was capable of rising off ground under it's own power. As I recall, it was not planned to use them for re-entry maneuvering -- they would likely be removed prior to space flight. I leave it to anyone really interested to look it up. >2) How fast do you thin the shuttle needs to go to get enough lift to >go UP? Right now, the shuttle decends at about 100 feet per second >throughout the re-entry: The thing does NOT fly, it drops like a brick. >The wings just increase the manoeverability. I've never seen a brick flare and land softly. It may require a large amount of thrust to make it sustain altitude or climb, but it doesn't have to be flying extremely fast. >3) The Shuttle is such a bizarre handling aircraft that pilots tend to >put it into PIO (Pilot Induced Oscillation). [...] This is >why it is NOT landed by pilots, but by the auto-land system. I watched >the pilots try to land it on the Rockwell simulator, and I NEVER saw >anybody do it: they ALWAYS crashed. The first landing on the runway >at Edwards by the Enterprise, in front of all the political luminaries, >was almost a disaster: they started that approach with the pilots >on the sticks, and the gound controllers had to shut them off because >they were approaching to structural limits of the airframe! The autoland >system greased it on that time, and has hit the numbers every time since. >The pilots DO NOT land the shuttle! [...] No kidding! Do you remember one of the early shuttle flights where just after touchdown, the nose got very high before it finally was lowered for main gear touchdown? That happened because the pilot flying made an error. That was no autoland system flying, but an old style human being. The shuttle is routinely hand flown through the final segment of the approach. It IS flown through a flight control computer and NOT by direct control (which is reported to be extremely difficult). BTW, there was a factual article that described the shuttle control system and hand flying techniques in either _Analog_ or one of the other major SF mags as early as 1977-78. At that time, mission pilots were practicing to proficiency in hand flying by direct control to touchdown. You'd probably really enjoying some technically correct articles. Aviation Week is available at libraries everywhere. Try it some time. -- Steve (the certified flying fanatic) steve@aurora.arc.nasa.gov
cjp@antique.UUCP (Charles Poirier) (10/13/88)
An American expert on the Soviet space program, whose name and credentials I can't put my finger on right now, recently spoke at AT&T Bell Laboratories. My recollection of his words of wisdom is as follows. The Soviet shuttle is currently undergoing atmospheric test flights. In this configuration, it does have air-breathing jet engines. Why? Because Soviet-built airplanes are less powerful than the 747 (I think?) on which we piggybacked Enterprise for our similar testing. They can't lift the weight on a plane, so it is self-powered. The space-going configuration, however, will not have jets. One other tidbit: the Soviet shuttle's equivalent of the SRB's will in fact be liquid-fueled engines. Apparently the Soviets have never developed or used large solid fuel rockets. Cheers, -- Charles Poirier (decvax,ucbvax,mcnc,attmail)!vax135!cjp "Docking complete... Docking complete... Docking complete..."
henry@utzoo.uucp (Henry Spencer) (10/13/88)
In article <3020@jpl-devvax.JPL.NASA.GOV> david@beowulf.JPL.NASA.GOV (David Smyth) writes: >... And, I'll bet a donut that it will fly with IBM 370s in >the racks, executing HAL/S software, just like ours. JUST like >ours. That's probably why they're having so much trouble with the software :-) (which is reported to be the pacing factor in the program at the moment). "Comrade, I *told* you we should have written our own rather than copying this American trash!!" ;-) -- 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
henry@utzoo.uucp (Henry Spencer) (10/13/88)
In article <1605@nunki.usc.edu> birenboi@sal18.usc.edu (Aaron Birenboim) writes: >Is there anybody else who has heard of Jets on the Shuttlesky? One hears conflicting stories about them, actually. My guess would be that they'll be on there for the operational flight, especially if the first flight is unmanned (which could make the landing kind of interesting). I could be wrong. -- 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
jwm@stdc.jhuapl.edu (Jim Meritt) (10/14/88)
I}In article <40869@linus.UUCP>, jp@linus.UUCP (Jeffrey Picciotto) writes: }> David Smyth writes: }> Assuming a reasonably slow rate of descent, doesn't this show that the }> shuttle could fly if it had useful and sufficiently powerful engines }> available? So, I suppose the answer is that anything with any lift at all will fly, }given enough thrust.... I was in on the sea trials of the AV-8B. Proof if I ever saw it that with enough power you can fly anything! (that sucker acts wierd!!!!) Disclaimer: Individuals have opinions, organizations have policy. Therefore, these opinions are mine and not any organizations! Q.E.D. jwm@aplvax.jhuapl.edu 128.244.65.5 (James W. Meritt)
knudsen@ihlpl.ATT.COM (Knudsen) (10/14/88)
There are NO solid rocket motors on the Soviet shuttle. The boosters and main rocket (under the "ET") are Energia liquid jobs. As for the jet engines, Newsweek implied that they are not currently installed, and might not be (tho they may have been included on earlier test flights). However, someone here pointed out that to truly *fly* a shuttle, you'd need some pretty powerful engines and lots of fuel to burn. My speculation is that whatever jets end up on the Russky orbiter will have just enough power to extend the glide path, maybe give one more appraoch if the 1st one is aborted early enough, but the engines would not be able to keep the shuttle up in level flight, even while the fuel lasts. Reminds me -- I still wonder whether, if our Shuttle somehow got dangerously below its landing glide path, the pilots might fire the hypergolic OMS engines in order to make it to the runway. -- Mike Knudsen Bell Labs(AT&T) att!ihlpl!knudsen "Lawyers are like handguns and nuclear bombs. Nobody likes them, but the other guy's got one, so I better get one too."
knudsen@ihlpl.ATT.COM (Knudsen) (10/14/88)
In article <1605@nunki.usc.edu>, birenboi@sal18.usc.edu (Aaron Birenboim) writes: > They STARTED development quite a while after us. I expect that their > computers, if nothing else, would be ahead of ours. Don't forget that in the USSR the 370 is the state of the art, tho for small stuff they can make an 8080 chip. At least that's the case for non-classified applications. At least that's what they'd like us to think. I'm sure the Soviets have enough Macs or STs or ATs whatever to raid for better chips. And whatever software development systems go with these. The subject of Soviet computer science and technology is fascinating. Those who've seen things over there continue to confirm a tremendous Soviet lag, but no way could they have seen the latest military limited-production stuff. Anyway, given the Russian tendency to stick with tried-and-true space hardware, I'd say that their Shuttleski's computers would be no more advanced than ours. -- Mike Knudsen Bell Labs(AT&T) att!ihlpl!knudsen "Lawyers are like handguns and nuclear bombs. Nobody likes them, but the other guy's got one, so I better get one too."
leem@jplpro.JPL.NASA.GOV (Lee Mellinger) (10/14/88)
In article <1605@nunki.usc.edu> birenboi@sal18.usc.edu (Aaron Birenboim) writes: |In article <3020@jpl-devvax.JPL.NASA.GOV> david@beowulf.JPL.NASA.GOV (David Smyth) writes: |>In article <1574@nunki.usc.edu> birenboi@sal6.usc.edu (Aaron Birenboim) writes: |>> | |The shuttle already has Flight control hardware, and a lot of hardware |for rocket engines. I am but a student, but I think that whatever |hardware that is necessary for the shuttle's rockets is larger |that whatever jet engine is needed to power the Shuttlesky. Unfortunately, |I cannot quote documents other than word of mouth of an ex director ^^^^^^^^^^^ |of JPL Deep Space Network. What have you seen that shows no Air intake? ^^^^^^^^^^^^^^^^^^^^^^^^^ |One photo which may have been re-touched is inconclusive. |Who knows, they may even have covers for the air intake durring launch. | |> | |Can this be said of Shuttlesky also, without much knowledge of their |design details? Does anybody have some estimates of the mass of |Shuttlesky? |If Shuttlesky can "fly" it would handle much better, although |the shape of Shuttlesky may raise some doubt. | |>4) I doubt that jet engines poweful enough to get that turkey flying |>would weigh less than the SSMEs. | |Do people who have worked with these systems think this is a valid accessment? | |>Conclusion: I think we will find that the soviet shuttle has only |>OMS and RCS rockets, no other form of propulsion. That does make it |>simpler. And, I'll bet a donut that it will fly with IBM 370s in |>the racks, executing HAL/S software, just like ours. JUST like |>ours. | |They STARTED development quite a while after us. I expect that their |computers, if nothing else, would be ahead of ours. | |Is there anybody else who has heard of Jets on the Shuttlesky? |(flames welcome) | |Aaron "The Lumberjack" Birenboim|"In the begining, the Universe was created... | | This made a lot of people angry, and was | GO TROJANS!! | widely reguarded as a bad move." | birenboi@castor.usc.edu | -Douglass Adams _The Guide_ I have worked at JPL for 13 years, 10 of those in the DSN, there is and has not been a "director" of the DSN. The closest that comes to that is the Assistant Laboratory Director for the Office of Tracking and Data Acquisition, which is the office that provides funding and technical direction for the DSN. There have been only two ALD's for TDA prior to the current occupant of that office, and one of those is deceased, the other is the current JPL Deputy Director. I am, therefore not convined of the worth of the statements that this person you talked to, made. Aviation Week has shown pictures of the Soviet Shuttle and made the point that the wing planform, the vertical stabliser, the shape and placement of the cockpit and overhead windows are all apparently identical with the US shuttle. In addition, they (the Soviets) have used insulating blocks on the skin that appear the be very much like the insulation on the shuttle. All in all, an excellent job of technology tranfer. Aviation Week also reported that there were jet engines installed for flight tests as others in the newsgroup have indicated. Lee -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- |Lee F. Mellinger Jet Propulsion Laboratory - NASA| |4800 Oak Grove Drive, Pasadena, CA 91109 818/393-0516 FTS 977-0516 | |-------------------------------------------------------------------------| |UUCP: {ames!cit-vax,psivax}!elroy!jpl-devvax!jplpro!leem | |ARPA: jplpro!leem!@cit-vax.ARPA -or- leem@jplpro.JPL.NASA.GOV | -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
alastair@geovision.uucp (Alastair Mayer) (10/14/88)
In article <820@super.ORG> laurel@super.UUCP (Michael Tighe) writes: >In article <1574@nunki.usc.edu> birenboi@sal6.usc.edu (Aaron Birenboim) writes: >> >> [.. stuff about Sov Shuttle not being a copy of US Shuttle ] >Rubbish! I have seen the Soviet Space Shuttle, and it is almost Oh really? Where? Or do you mean you've seen pictures of it. >identical to ours. In fact, most Americans would not be able to >tell the difference between it and ours (except for the CCCP marking >on the left wing). The most obvious difference I noticed was that >the SRB's are much shorter. Other than that, its' a genuine Not very observant, are you? They're not *S*RBs, they're *L*RBs - liquids, not solids, and there are four of them on the Energia core vehicle that launches shuttleski. The main engines are also on the Energia core, not the shuttle. Because there are no main engines there's no need to hang the OMS engines and fuel in pods, so the aft end is missing those bulges adjacent to the tail. Wing angles and overall length/width ratio look to be slightly different, too. Most of this can be determined by looking at the picture of the Soviet shuttle that appeared in Newsweek. >example of technology transfer. First flight is scheduled for early >December; delayed probably by a need to redesign the O rings. Liquid boosters don't need O-rings.
henry@utzoo.uucp (Henry Spencer) (10/15/88)
In article <820@super.ORG> laurel@super.UUCP (Michael Tighe) writes: >Rubbish! I have seen the Soviet Space Shuttle... In person? When? > In fact, most Americans would not be able to >tell the difference between it and ours (except for the CCCP marking >on the left wing). Most Americans don't know the difference between a planet and a star. (Really.) >The most obvious difference I noticed was that >the SRB's are much shorter. Other than that, its' a genuine >example of technology transfer. First flight is scheduled for early >December; delayed probably by a need to redesign the O rings. There are no O-rings, since there are no SRBs. (The things that look like SRBs are four -- not two -- liquid-fuel boosters.) Please don't sound off unless you know what you're talking about. -- 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
tif@cpe.UUCP (10/15/88)
Written 9:13 am Oct 12, 1988 by phred.UUCP!petej in cpe:sci.space.shuttle >I saw a Shuttle taped special once that said the commander, (I >forget who and what Shuttle it was), "was going to try to hit the numbers". >He greased it right on the numbers. The Auto-land system would not have >been able to do that except by luck. Is that last statement one of fact or opinion? That seems counter-intuitive. Paul Chamberlain Computer Product Engineering, Tandy Corp. {convex,killer}!ninja!cpe!tif
phil@titan.rice.edu (William LeFebvre) (10/16/88)
In article <3020@jpl-devvax.JPL.NASA.GOV> david@beowulf.JPL.NASA.GOV (David Smyth) writes: >3) The Shuttle is such a bizarre handling aircraft that pilots tend to >put it into PIO (Pilot Induced Oscillation). The center of pitch is >several airframe lengths in front of the vehicle: when you pull back on >the stick, the craft "feels" like it begins to sink quicker, when you >push forward on the stick, it "feels" like it starts to go up! This is >why it is NOT landed by pilots, but by the auto-land system. I watched >the pilots try to land it on the Rockwell simulator, and I NEVER saw >anybody do it: they ALWAYS crashed. The first landing on the runway >at Edwards by the Enterprise, in front of all the political luminaries, >was almost a disaster: they started that approach with the pilots >on the sticks, and the gound controllers had to shut them off because >they were approaching to structural limits of the airframe! The autoland >system greased it on that time, and has hit the numbers every time since. >The pilots DO NOT land the shuttle! Then why did NASA go to the bother of having an extra set of controls added to a standard jet aircraft in such a way that the controls made the plane feel more or less like the shuttle during landing? Why do the pilots use this aircraft to practice approaches and landings? My wife watched one of her co-workers in the simulator in building 5 at the Johnson Space Center perform a successful landing. And this guy is NOT an astronaut and has never had any official training as an astronaut. He has a pilot's license, yes, and he knows quite a bit about the shuttle, yes (being a flight controller), but he is not an astronaut. I think you are seriously confused. The computers *assist* the pilots in landing, but the pilots still control the craft. The computers enhance the controls for the pilots, but the pilots *still* control the craft. How can the on-board computers "hit the numbers" exactly when they can't even be all that accurate about the vehicle's exact position? And if you wonder what I am talking about, watch for an upcoming posting of mine about the mysterious "vector to BFS" call. I have learned quite a bit more about that, and it is very enlightening. William LeFebvre Department of Computer Science Rice University <phil@Rice.edu>
phil@titan.rice.edu (William LeFebvre) (10/16/88)
In article <1703@eos.UUCP> steve@eos.UUCP (Steve Philipson) writes: >In article <3020@jpl-devvax.JPL.NASA.GOV> david@beowulf.JPL.NASA.GOV (David Smyth) writes: >>2) How fast do you thin the shuttle needs to go to get enough lift to >>go UP? Right now, the shuttle decends at about 100 feet per second >>throughout the re-entry: The thing does NOT fly, it drops like a brick. >>The wings just increase the manoeverability. > > I've never seen a brick flare and land softly. It may require a >large amount of thrust to make it sustain altitude or climb, but it >doesn't have to be flying extremely fast. Quite right. I watched this last landing very closely, and decided that the shuttle can glide very nicely when it wants to. After the flare and on final approach, it looks like a regular plane coming in for a landing. I believe that it "drops like a brick" not for aerodynamic reasons, but because that's the only way to get the shuttle down to the right altitude in a reasonable amount of time. William LeFebvre Department of Computer Science Rice University <phil@Rice.edu>
peter@sugar.uu.net (Peter da Silva) (10/16/88)
In article <1988Oct14.170004.1668@utzoo.uucp>, henry@utzoo.uucp (Henry Spencer) writes: > Most Americans don't know the difference between a planet and a star. > (Really.) Many Americans, for example TV scriptwriters and actors, can't tell the difference between a planet and the Trifid Nebula. Ref: Space:1999. Scene: a bunch of actors standing around a picture of the Trifid Nebula pasted to the wall, ostensibly a videoscreen. Comment: "Is that a planet?" Reply: "I don't know."... -- Peter da Silva `-_-' peter@sugar.uu.net Have you hugged U your wolf today?
henry@utzoo.uucp (Henry Spencer) (10/16/88)
In article <7195@ihlpl.ATT.COM> knudsen@ihlpl.ATT.COM (Knudsen) writes: >Reminds me -- I still wonder whether, if our Shuttle somehow >got dangerously below its landing glide path, the pilots might >fire the hypergolic OMS engines in order to make it to the runway. They're not powerful enough to do any good. -- 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
jbrown@jato.Jpl.Nasa.Gov (Jordan Brown) (10/17/88)
In article <2008@kalliope.rice.edu> phil@Rice.edu (William LeFebvre) writes: >Quite right. I watched this last landing very closely, and decided that >the shuttle can glide very nicely when it wants to. After the flare and >on final approach, it looks like a regular plane coming in for a landing. Even a brick (well...) can flatten its glide path by turning speed into altitude (or lack of descent in this case). Remember, the Shuttle crosses the EDW field boundary at Mach 1 and touches down at ~200 mph; that energy has to go *somewhere*, and I believe it's used in the last segment of the flight to flatten the glide.
craig@think.COM (Craig Stanfill) (10/17/88)
> I've never seen a brick flare and land softly. It may require a >large amount of thrust to make it sustain altitude or climb, but it >doesn't have to be flying extremely fast. It doesn't require thrust to sustain altitude or climb, it requires VEOLCITY. At Mach 18, a brick is quite capable of sustaining, climbing, or doing anything it wants to, provided it can be controlled. Landing is a bit more constrained: 1) Your brick must be controllable. 2) The velocity needed for the brick to sustain altitude (or nearly so) must be slow enough to permit landing. 3) Your brick must be able to reach this level-flight velocity by gliding. 4) The brick needs to be able to pull out of the glide. These constraints are not incredibly difficult to meet. - Craig Stanfill
laurel@super.ORG (Our Friends Up the Way) (10/18/88)
Recently an article I posted has generated some mail and some postings. I am going to take this opportunity to clarify what I said. The article I responded to had the following text: >THE SOVIET SHUTTLE HAS JET ENGINES. The soviet shuttle is actually a >full fledged PLANE. They have flown it around, and it has the ability >to take off from the ground, as a plane does! This make the SSS sound like some kind of MiG. I answered with the following text: >Rubbish! I have seen the Soviet Space Shuttle, and it is almost >identical to ours. In fact, most Americans would not be able to >tell the difference between it and ours (except for the CCCP marking >on the left wing). Then to my regret, I added: >The most obvious difference I noticed was that the SRB's are much >shorter. Other than that, its' a genuine example of technology >transfer. First flight is scheduled for early December; delayed >probably by a need to redesign the O rings. Unfortunately a few readers took these last comments seriously; Come on! This is obviously a facetious statement. Like I know when the Soviets are going to launch? I don't know when NASA is going to launch (and neither do they). My apologies for injecting a little humor into the topic. Sure, I could have said the Energia or liquid-fuel boosters, but as they say at the newspaper, "Why let the facts interfere with a good story?" (more humor). I found it odd that the readers that knew the booster rocket story was wrong respond to it but did not respond to the errors in the original posting about the SSS being a plane. Better check your AW&ST subscription. -- Michael Tighe Supercomputer Research Center ARPA: laurel@super.org
adolph@ssc-vax.UUCP (Mark C. Adolph) (10/18/88)
In article <2008@kalliope.rice.edu> phil@Rice.edu (William LeFebvre) writes: >Quite right. I watched this last landing very closely, and decided that >the shuttle can glide very nicely when it wants to. After the flare and >on final approach, it looks like a regular plane coming in for a landing. I believe that the Enterprise drop-tests revealed that the shuttle got better ground effect lift than was anticipated. I'd like to see them flare that thing at 8000 feet and ride some thermals for a while :-). -- -- Mark A. ...uw-beaver!ssc-vax!adolph
steve@eos.UUCP (Steve Philipson) (10/18/88)
In article <29318@think.UUCP> craig@kulla.think.com.UUCP (Craig Stanfill) writes: >> I've never seen a brick flare and land softly. It may require a >>large amount of thrust to make it sustain altitude or climb, but it >>doesn't have to be flying extremely fast. > >It doesn't require thrust to sustain altitude or climb, it requires >VEOLCITY. At Mach 18, a brick is quite capable of sustaining, >climbing, or doing anything it wants to, provided it can be >controlled. Landing is a bit more constrained: Your are incorrect. Energy input is required. Velocity can be traded for lift, but drag is generated in the process; velocity is lost. If you want to maintain velocity and altitude, or climb, you've got to add energy somewhere. The usual method is to add thrust. Sailplanes use updrafts, but the orbiter has too high a sink rate for that. If all that was needed was velocity, than your controllable brick could fly around indefinitely once it reached Mach 18. This is obviously wrong. You might have noticed that supersonic fighters require massive amounts of thrust to operate even at Mach 2 to 3. >4) The brick needs to be able to pull out of the glide. You can make a brick controllable by putting fins on it, but it still won't generate significant lift, it won't glide, and it won't flare (flatten it's approach trajectory) and is NOT capable of landing. You could raise the "nose", but with the shape of a brick you're not going to get much (if any) lift at reasonable speeds. Sure, force is generated by a flat plate at hypersonic speeds, but the orbiter doesn't need supersonic velocity to generate lift; the landing flare is accomplished below 300 kts. A brick that's shaped to generate lift isn't a brick anymore but has become a wing, or at least a lifting body. The orbiter isn't a brick, even though its lift to drag ratio is low. The constraints on shape are considerably more extensive than you imply. -- Steve (the certified flying fanatic) steve@aurora.arc.nasa.gov
cbs@geac.UUCP (Chris Syed) (10/18/88)
In article <29318@think.UUCP>, craig@think.COM (Craig Stanfill) writes: > > It doesn't require thrust to sustain altitude or climb, it requires > VEOLCITY. Well... as I recall from 101, there are four forces acting on an aircraft: ^ lift < thrust drag > weight V It would be more correct to say that _lift_ is required. Lift is produced by the velocity of the air passing over the airfoil, which has to be greater than the velocity of air passing under the airfoil to create a pressure difference). You get this effect in part by the aircraft's speed, and in part by the curvature of the wing and its angle of attack. If you tip the wing up, you get more lift. If you tip it too much, you stall. To get better lift at low velocities, most aircraft extend their wing surfaces and change their lift-producing characteristics by using flaps, (the jumbos use Fowler flaps which are almost big enough to be considered 'second wings'), and by using a high angle of attack. Many designs also incorporate "leading edge devices" to produce more lift at low airspeeds. Of course, the flaps are also meant to decrease the speed of the craft by inducing more drag. The shuttle dosen't have enormous flaps, (at least I don't think so). This means you must rely on speed, natural characteristics of the wings, and the angle of attack to get your lift on final approach. {uunet!mnetor,unicus,yunexus,}!geac!cbs (Chris Syed)
henry@utzoo.uucp (Henry Spencer) (10/21/88)
In article <828@super.ORG> laurel@super.UUCP (Michael Tighe) writes: >Unfortunately a few readers took these last comments seriously; >Come on! This is obviously a facetious statement... No, it's either a facetious statement or an ignorant statement. The latter type is far from unknown in this newsgroup and others. Look folks, if you want to be funny, mark it with ":-)". Not doing so is the mark of an inexperienced or careless news poster; this is not a medium that conveys subtlety well. > I found it odd that the readers that knew the booster rocket >story was wrong respond to it but did not respond to the errors >in the original posting about the SSS being a plane... The fact is, nobody's quite sure what the status of the jet engines on the Soviet shuttle is, since there have been conflicting stories for a long time. The booster question is fairly well settled. -- 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
fosler@inmet.UUCP (10/22/88)
Taken from "Shuttle Down" by Lee Correy Shuttle Orbiters usually landed under automatic control, guided by the superaccurate Microwave Scanning Beam Landing System on the ground. There must be a better source then this? My understanding is that MSBLS does not exist at most airports and if the shuttle must land anywhere that doesn't have MSBLS then the pilots must manually land it. Carl Fosler