From: skunk-works-digest-owner@mail.orst.edu To: skunk-works-digest@mail.orst.edu Subject: Skunk Works Digest V5 #207 Reply-To: skunk-works-digest@mail.orst.edu Errors-To: skunk-works-digest-owner@mail.orst.edu Precedence: bulk Skunk Works Digest Tuesday, 28 February 1995 Volume 05 : Number 207 In this issue: Connecting to Harbor Belgian Lawn Dart Data Re: info Re: Belgian Lawn Dart Data British Stealth RE: British Stealth British Stealth Re: British Stealth Administrivia mach 1+ props too much stealth Re: too much stealth Mach 1+ Prop. stealth... Re: Supersonic Props Re: Supersonic Props Re: Supersonic Props Re: stealth... Re: Supersonic Props Re: Supersonic Props See the end of the digest for information on subscribing to the skunk-works or skunk-works-digest mailing lists and on how to retrieve back issues. ---------------------------------------------------------------------- From: JMTN47A@prodigy.com (MR DEAN W SMEATON) Date: Wed, 22 Feb 1995 14:23:33 EST Subject: Connecting to Harbor Please advise telephone number for Harbor. Thank you. - -------FORWARD, Original message follows------- Date: FROM: ID: Subject: Connecting to Harbor - -------FORWARD, End of original message------- ------------------------------ From: "Robert S. Hopkins, III" Date: Wed, 22 Feb 1995 16:33:14 -0500 Subject: Belgian Lawn Dart Data I shared the recent data posted here concerning the path and altitude of an unidentified a/c tracked by Belgian F-16s. I shared this info with an F-14 RIO instructor, who responded with these comments, that merit some consideration. All >of the track data is computer generated and subject to lots of >computational errors. Most of the time >the sytems are pretty good but they do make mistakes. Like clouds >closing [in at] you at 1500 mph. I don't know the reliability of the F-16 >system, >but every set has gremlins. > >The "diamond shape" is probably the computer generated video on >the radar as very few still display raw radar returns, we [F-14] had both - >the DDD (upper scope) displayed raw video and the TID (the large >lower scope) displayed computer generated symbology. As for the >physics of the event most of the descent was 1,000 meters a second or >60,000 meters a minute = 198,000 feet per minute = about 2200 mph. > >Not likely to be a stealth acft at that speed, particluarly if on >radar. Also at that speed there should have been some real nice >sonic booms associated with the acft particularly as it approached >low level. > >Lastly, it was in Paris Match - not AW&ST by a long shot. Sounds >closer to an Enquirer type of article. Probably flown by Elvis and >JFK. > At some 2200 mph and at extremely low altitude, the sonic boom should have blasted quite an area with lots of broken windows, startled animals, and no doubt one or two premature births. Still too many open issues to consider this anything other than an anomaly. Robert S. Hopkins, III Corcoran Department of History Randall Hall University of Virginia Charlottesville VA 22906 internet: rsh8s@virginia.edu ------------------------------ From: John Regus Date: Wed, 22 Feb 1995 19:50:20 -0500 (CST) Subject: Re: info Do you know which specific areas are being effected, such as information technology, data/tecom? Thanks, John F. Regus | (713) 960-0045 | SYS/370/390 SYSTEM SOFTWARE ENGINEERING WUI:REGUSHOU | On Mon, 20 Feb 1995, JOHN wrote: > Hope this does not have an major effect on the Skunk-works > > press-release@augusta.lmsc.lockheed.comm > Subj: Lockheed to Lose 800 Jobs Through June > > LOCKHEED TO LOSE 800 JOBS THROUGH JUNE > > SUNNYVALE, California, February 20, 1995 -- Lockheed > Missiles & Space Co. (LMSC) will reduce its workforce by 800 > jobs by the end of June, according to Vance Coffman, > executive vice president of Lockheed Corporation and acting > president of LMSC. > Despite significant consolidations of LMSC facilities > and functions, he said, our analysis of the competitive > marketplace "indicates we must effect further streamlining > of our ways of doing business." > For the second half of 1995, he added, "further > reductions of a similar magnitude could be necessary, driven > by continuing competitive analysis and our evaluation of the > situation in June." > The newly announced reductions will cut across all > areas -- technical, administrative and managerial. > For employees who lose their jobs, LMSC will continue > to offer a range of services through its Career Transition > Center. The center is staffed mainly by NOVA, the Santa > Clara Valley private industry council that helps clients > during employment transition. > # # # > February, 1995 95-19 > > Contact: Bob Burgess (408) 742-7442 > Jim Graham (408) 742-7531 > > ------------------------------ From: "J. Pharabod" Date: Thu, 23 Feb 95 11:58:13 MET Subject: Re: Belgian Lawn Dart Data >I shared the recent data posted here concerning the path and altitude >of an unidentified a/c tracked by Belgian F-16s. I shared this info >with an F-14 RIO instructor, who responded with these comments, >that merit some consideration. >Robert S. Hopkins, III (Wed, 22 Feb 1995 16:33:14 -0500) Thank you very much for this inquiry. Unfortunately, it seems that some misunderstandings or transmission errors occurred during the process: >> [...] . As for the >>physics of the event most of the descent was 1,000 meters a second or >>60,000 meters a minute = 198,000 feet per minute = about 2200 mph. No, it was 1,000 feet a second (time 12 seconds: altitude 11,000 feet; time 22 seconds: altitude 0). Only 700 mph (mean value). >>Not likely to be a stealth acft at that speed, particluarly if on >>radar. Also at that speed there should have been some real nice >>sonic booms associated with the acft particularly as it approached >>low level. See above. >>Lastly, it was in Paris Match - not AW&ST by a long shot. Sounds >>closer to an Enquirer type of article. Probably flown by Elvis and >>JFK. The transcript I posted did not come from Paris Match. It is annex I (the letter I, not the number 1) to the report published by the Belgian Air Force staff, title: "Report on the observation of UFOs during the night of March 30-31, 1990". I have the report itself (public) and its annexes (not published, at least when I got them). Thanks again for having investigated. J. Pharabod ------------------------------ From: seb@tadpole.co.uk (Steven Barber) Date: Fri, 24 Feb 95 11:29:39 GMT Subject: British Stealth In this week's Electronic Times, the frontpage headline article is dedicated to British aviation stealth news. The headline is: "BAe invests in stealth" - BAe = British Aerospace. The article goes on to say that BAe are building a dedicated site for development work on the Future Offensive Aircraft (FOA) program, a Tornado replacement. The site, quote. "will play a similar role to the Lockheed's Skunk Works in California, where development of the F16 fighter replacement is under way." It goes on to say "A major part of the aircraft's exterior design has already been completed using the Supercomputing Centre at Farnborough." Hmmmmmmmmmmm Well, what does everyone make of that? Steve ------------------------------ From: George Allegrezza 24-Feb-1995 0746 Date: Fri, 24 Feb 95 07:49:52 EST Subject: RE: British Stealth One of the last few issues of Aviation Week has a series of articles on black programs. One article mentions the existence of a British program to develop a fighter-size stealth aircraft, with empahsis on the radar signature from the forward aspect. That's conceptually the easiest to deal with from the design standpoint and has the biggest payoff. This would tie in with both the mission and time frame of a Tornado successor. It seeems likely that, now that the US has blazed the trail, most if not all of the major aviation powers will try to develop some kind of stealth aircraft or missile. George George Allegrezza | Digital Equipment Corporation | "Thunder is good. Thunder is impressive. But Mobile Systems Business | it's lightning that does all the work." Littleton MA USA | allegrezza@ljsrv2.enet.dec.com | -- Mark Twain ------------------------------ From: "RUSSELL.B" Date: 24 Feb 1995 08:04:08 GMT Subject: British Stealth Date: Friday, 24 February 1995 8:04am ET To: Internet From: RUSSELL.B@GOMAIL Subject: British Stealth As long as we don't try to recreate the events of 1812 then any advance in this type of technology is a good thing, no matter which side of the pond it comes from. Just remember to please share (but only with your american cousins). Just another software type question. Bob Russell Systems Programmer State of Georgia DOAS ------------------------------ From: BaDge Date: Fri, 24 Feb 1995 13:56:40 -0500 (EST) Subject: Re: British Stealth On Fri, 24 Feb 1995, Steven Barber wrote: > In this week's Electronic Times, the frontpage headline article is > replacement. The site, quote. "will play a similar role to the Lockheed's > Skunk Works in California, where development of the F16 fighter replacement > is under way." It goes on to say "A major part of the aircraft's exterior > design has already been completed using the Supercomputing Centre at > Farnborough." Oopsie do! Good catch, Steve Anyone have an ftp or homepage site for the Supercomputing Centre at Farnborough? regards, BaDge ------------------------------ From: Kean Stump Date: Fri, 24 Feb 1995 15:01:55 PST Subject: Administrivia We're moving the ftp archives around a bit this weekend; if we screw up the digest processing may have problems. This message will be a test. 8) Kean Kean Stump Information Services kean@ucs.orst.edu Oregon State University OSU doesn't pay me to have official opinions. (503)-737-4740 ------------------------------ From: "Frank Schiffel, Jr." Date: Sat, 25 Feb 95 18:48:34 CST Subject: mach 1+ props I seem to recall that there was a P-47 that had a supersonic prop. Only there were problems with it setting up vibrations around the aircraft that really made the ground crew (and the pilot) nauseous. It was test flown at Edwards (natch) around 45-50 timeframe (probably closer to 45 or 46). Of course, with the jet engine the whole idea of supersonic props was moot. Recall, the amount of trouble (and amount of aircraft lost) using propellors vs. now with jets. I seem to recall 45000 as a figure in 1945 for the Air Corps as accident losses. ------------------------------ From: TIMEDOC Date: Sun, 26 Feb 1995 12:38:11 -0500 (EST) Subject: too much stealth Perhaps I am naieve or mistaken, but in order for anyone else to truly get stealthly aircraft, America would have to be letting these other "allies" in on a few of our secrets. And with the climate the world is in right now, any two-bit terrorist nation with grudge or semi-superpower without it would love just a few stealth planes to wreak havoc with. If America truly is giving this technology away, especially to European countries, the world will have it soon. Although the British, at least I think, can be trusted, things in Europe tend to leak out and spread like wildfire. I'm not coming from some "keep *us* superior" attitude, I'm just afraid that if our government thinks that we are in some kind of advantagious position we'll get burned worse than the World Trade Center. - -G P.S. If anyone out there can tell me the best place to keep up on the leading edge of tech. research (especially military) I would appreciate the help! ------------------------------ From: kuryakin@arn.net (Illya Kuryakin) Date: Sun, 26 Feb 1995 11:12:50 -0600 Subject: Re: too much stealth >Perhaps I am naieve or mistaken, but in order for anyone else to truly get >stealthly aircraft, America would have to be letting these other "allies" >in on a few of our secrets. And with the climate the world is in right now, If one reads sources like Ben Rich's autobiography, then one realizes that Lockheed made stealth by utilizing Russian research that I presume anyone with proper 'connections' could access. If you have someone in your company that can follow the theory/research, then given that Lockheed has already used it effectively, it wouldn't be hard to realize that many companies will be following in their path. Or coming up with their own ideas. And besides, enough has been published openly to at least point in the directions one needs to take to develop stealth. Nah, I don't think that we even _need_ to have deliberately given it to them, although it's not impossible for it to have happened. I don't see any conspiracy. Illya ------------------------------ From: "RUSSELL.B" Date: 27 Feb 1995 08:52:08 GMT Subject: Mach 1+ Prop. Date: Monday, 27 February 1995 8:52am ET To: Internet From: RUSSELL.B@GOMAIL Subject: Mach 1+ Prop. On Sat, 25 Feb 95 Frank Schiffel, Jr. wrote, >I seem to recall that there was a P-47 that had a supersonic prop. Only >there were problems with it setting up vibrations around the aircraft >that really made the ground crew (and the pilot) nauseous. It was test >flown at Edwards (natch) around 45-50 timeframe (probably closer to >45 or 46). Of course, with the jet engine the whole idea of supersonic >props was moot. Recall, the amount of trouble (and amount of aircraft lost) >using propellors vs. now with jets. I seem to recall 45000 as a figure in >1945 for the Air Corps as accident losses. I think what Frank was thinking about was a modified F-84 that was fitted with a nose/puller propeller. I don't remember the mod letter but "WINGS" on the Discovery channel did a good story about the whole F-84 series. It was a strange looking beast though. Was this the first turbo-prop aircraft ? Just another software type question. Bob Russell Systems Programmer State of Georgia DOAS ------------------------------ From: I am the NRA Date: Mon, 27 Feb 95 17:38:39 EST Subject: stealth... >Perhaps I am naieve or mistaken, but in order for anyone else to truly get >stealthly aircraft, America would have to be letting these other "allies" >in on a few of our secrets. There are no secrets. There are just application tricks to the laws of physics. U can by RCS packages to run on PCs over the counter. I posted name of one such here last year. There is no "magic potion, grown only at Groom Lake" to make this work. As someone else pointed out (to clarify a bit) a lot of this work STARTED with a Russian written package that eased solutions to the math involved. I wager several cookies that's been expanded, a lot, by now. >And with the climate the world is in right now, any two-bit terrorist nation >with grudge or semi-superpower without it would love just a few stealth planes >to wreak havoc with. All it takes is money (that MAY be the magic elixir...) and the will to get on with it. The USSR would have had "the bomb" even without intel assist. Just a matter of letting the physicists whittle away. >If America truly is giving this technology away, One suspects "Sell" is whats involved. Or semi swop, say for Chobahm technology... >especially to European countries, the world will have it soon. Any decent aerodymicist & physicist team can do it now. The trick is to realize that it CAN be done. regards dwp ------------------------------ From: larry@ichips.intel.com Date: Mon, 27 Feb 1995 16:33:21 -0800 Subject: Re: Supersonic Props Doug Tiffany writes: >It's been kind of slow these last couple of days, so maybe some people >won't mind if I ask an off topic question. I was wondering if some of >the aircraft experts out there could tell me why the speed of a >propeller should (or could) not exceed the speed of sound. I read >this fact in an article once, and it was mentioned on "Wings" (on the >Discovery Channel), but they never explained why. > >Thanks in advance. Since this has been sitting around for awhile, let me take a shot at it, perhaps someone can embellish: Propeller engines do not exhibit constant thrust as the Mach number increases towards supersonic, they loose thrust as speed increases due to increased drag on the propeller. The reason for the drag rise is the same as the reason for the drag rise on a wing as the speed goes up, which we've talked about before, namely the critical Mach number. The speed we're talking about is both the forward speed of the aircraft and the tip speed due to rotation of the propeller, although different parts of the propeller blade are the big source of drag rise in each. During WWII, this became a real problem as aircraft started to approach 500 mph. The problem was eventually solved and the solutions were demonstrated after the war (some people posted some information on some of the test vehicles that were used) but because of jets, nobody cared. It would have been neat to see, say, an XP-72, tested with such a propeller. ------------------------------ From: mangan@edac1.kodak.com (Paul Mangan) Date: Tue, 28 Feb 95 08:07:19 EST Subject: Re: Supersonic Props Doug Tiffany writes: >............... I was wondering if some of > >the aircraft experts out there could tell me why the speed of a > >propeller should (or could) not exceed the speed of sound. I read > >this fact in an article once, and it was mentioned on "Wings" (on the > >Discovery Channel), but they never explained why. AND Larry responds: > Since this has been sitting around for awhile, let me take a shot at it, > perhaps someone can embellish: > > Propeller engines do not exhibit constant thrust as the Mach number > increases towards supersonic, they loose thrust as speed increases due > to increased drag on the propeller. > > The reason for the drag rise is the same as the reason for the drag rise on > a wing as the speed goes up, which we've talked about before, namely > the critical Mach number. > > The speed we're talking about is both the forward speed of the aircraft > and the tip speed due to rotation of the propeller, although different > parts of the propeller blade are the big source of drag rise in each. > > During WWII, this became a real problem as aircraft started to approach > 500 mph. > > The problem was eventually solved and the solutions were demonstrated > after the war (some people posted some information on some of the test > vehicles that were used) but because of jets, nobody cared. > > It would have been neat to see, say, an XP-72, tested with such a > propeller. > AND I add: When I was very young my Dad worked for Bell Aircraft. There used to be informal meetings at our house....kind of a picnic.... I wasn't allowed to go near them except to deliver beer or snacks. I remeber once (and I'm sure I'm not accurate) a conversation I overheard stating that They wanted to break the sound barrier using a propeller driven aircraft. One of the worries was the political impact it could have on the X1 but the thing that sticks out in my mind was that there was a schock wave that went down the prop as they went through the barrier and they didn't think the blade would hold together during transition. Please no flames these are dull memories of 40 years ago and I was only about 10 then so nothing really made sense to me. Paul mangan ------------------------------ From: elukas@eagle.wbm.ca (Edward Lukas) Date: Tue, 28 Feb 1995 07:27:25 GMT Subject: Re: Supersonic Props Reference Doug Tiffany's interest in supersonic propellers. In general aviation a float equipped Cessna 185 can be equipped with either a 2-bladed or 3-bladed constant speed prop. The 2-bladed version is a few inches longer. Although the 3-bladed prop has a 'smoother' operation and better performance at cruise power settings; the 2-bladed prop can not be beat at redline RPM, max T.O. weight & low airspeed (ie: Takeoff). The sound at take-off is a distinct chop/chop/chop. This is the sound emminating from the tips as they approach (or surpass) supersonic velocities. Regards from the white hinterland ... Ed Lukas ------------------------------ From: "Christian Jacobsen" Date: 28 Feb 1995 09:10:07 U Subject: Re: stealth... Subject: Time:8:56 AM OFFICE MEMO RE>stealth... Date:2/28/95 >>And with the climate the world is in right now, any two-bit terrorist nation >>with grudge or semi-superpower without it would love just a few stealth planes >>to wreak havoc with. > All it takes is money (that MAY be the magic elixir...) and the will to > get on with it. Money would definitely be an issue, but I think an even larger issue would be how to test such a plane. The US being such a large nation (square foot-wise), there are a lot of unoccupied area in which to fly a semi-secret or totally secret craft. A small nation like Iraq would have a hard time keeping their developments (or launches) a secret. It seems like the biggest benefit of the F117 is that nations like Iraq have no idea when to look for it, or where it will come from. If you were Iran, let's say, there are only a few places within Iraq's borders that you would have to keep an eye on to watch for stealthy craft. This seems like it would take a lot of the stealthiness out of the equation. In flight, the low RCS would still work its magic, but the plane has to get up in the air without being seen to be a real surprise. Just my 2 cents worth... - - Christian ------------------------------ From: Kathryn & Andreas Gehrs-Pahl Date: Tue, 28 Feb 1995 12:31:06 -0500 (EST) Subject: Re: Supersonic Props The main reason, why no propeller-driven aircraft has flown at Mach 1 (or Mach 1+) is that it is easier and (and cheaper) to accomplish this with an repulsion (jet / rocket) type engine. The fastest propeller-driven aircraft is still the Russian Tu-95/Tu-142 series of turboprop powered, counter-rotating propeller-driven bombers (NATO code name 'Bear'). The USAF tested in the 1950s the use of turboprops for fighters. Under project MX-3347, Republic built two XF-106 -- later redesignated XF-84H -- which used Allison XT40-A-1 turboprops and supersonic propellers. The two aircraft (Model AP.46, USAF serials 51-17059 / 51-17060) were tested with different types of supersonic propellers, which worked, but were very loud and reportedly caused ground crews and pilots to experience nausea. The 5,850 hp Allison XT40 seemed not suitable as a fighter engine, and the project was canceled. The first aircraft flew for the first time on July 22, 1955 from Edwards AFB, CA, piloted by Republic test pilot Henry Beaird. The aircraft was also known as the 'Thunderscreech', but this was only a nickname and not an official DoD 'popular name'. In the 1980s, the European -- maybe Swiss, Austrian or German ? -- designer, Collani (sp), made a mock-up of a propeller-driven Mach-1 capable aircraft, but I don't know how serious the project was. At the end of the 1980s, someone in the USA planned to 'break the sound barrier' in a propeller-driven aircraft, dubbed the 'Mach Buster'. The project (in various stages of construction) was displayed several times at Oshkosh, but it seems to have come to a stop, because of budget problems. As far as I know, this aircraft would have used a piston engine!?! If prop-fans are considered as being some sort of propellers, I would think that a prop-fan equipped aircraft has the best efficiency at higher speeds, creating the least amount of induced drag when reaching transonic speeds. But I am only an armchair aerodynamicist, so maybe someone can correct me here. - -- Andreas - --- --- Andreas & Kathryn Gehrs-Pahl Absolute Software 313 West Court St. #305 schnars@umcc.ais.org Flint, MI 48502-1239 Tel: (810) 238-8469 - --- --- ------------------------------ From: HACKETT@vilas.uwex.edu Date: Tue, 28 Feb 1995 11:35:15 CDT Subject: Re: Supersonic Props .The main reason, why no propeller-driven aircraft has flown at Mach 1 (or Mach 1+) is that it is easier and (and cheaper) to accomplish this with an repulsion (jet / rocket) type engine. This may already have been discussed but I seem to recall P-51s exceeding the Mach One during power dives. Does that count? ------------------------------ End of Skunk Works Digest V5 #207 ********************************* To subscribe to skunk-works-digest, send the command: subscribe skunk-works-digest in the body of a message to "majordomo@mail.orst.edu". 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