From: skunk-works-digest-owner@harbor.ecn.purdue.edu To: skunk-works-digest@harbor.ecn.purdue.edu Subject: Skunk Works Digest V2 #10 Reply-To: skunk-works-digest@harbor.ecn.purdue.edu Errors-To: skunk-works-digest-owner@harbor.ecn.purdue.edu Precedence: bulk Skunk Works Digest Friday, 20 November 1992 Volume 02 : Number 010 In this issue: Re: F-117 Article (1-3) Re: F-117 V. E-2 Re: F-117 V. E-2 Re: F-117 V. E-2 Re: Copying Articles Re: Copying Articles Re: F-117 V. E-2 Re: F-117 V. E-2 Re: F-117 V. E-2 Re: F-117 V. E-2 Stealth VS Radar Re: F-117 Article (1-3) Re: F-117 Article (1-3) Re: F-117 Article (1-3) Re: F-117 Article (1-3) SR-71 Development 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: Blair Haworth Date: Tue, 17 Nov 92 08:01:53 EST Subject: Re: F-117 Article (1-3) >> [Nick] I'm probably being overly paranoid or formal or >>something, but the (presumably unauthorized) copying of >>that much (presumably) copyrighted material makes me >>nervous. I'm more comfortable with short excerpts and >>enthusiastic recommendations that we all find the original >>issue and read it. >[Dave] Wouldn't that come under the umbrella "U.S. >government work not protected by U.S. copyright" anyway? _Air Force_ isn't a government publication; it's the organ of the Air Force Association, an extra-service lobbying, outreach, and professional group like AUSA and the Naval Institute. Note however, that its "newsstand price" (ever seen it on a newsstand?) is almost certainly at or below cost, given its circulation, size, and use of glossy paper/color printing. It's largely (not entirely) an outreach publication and disseminating it to a bunch of enthuiaists - prime candidates for AFA membership - at no (palpable) cost probably isn't going to put anyone's nose out of joint. Now if, say, the Center for Defense Information tried the same thing, there'd be trouble, and all copyrighted hell would likely break loose... N.B.: I'm not a lawyer, nor a member nor a representative of AFA, and all of the above is strictly speculative. It's certainly not a good idea to post masses of copyright material, I just say that in this case it's nothing to work up a sweat over. -- Blair Haworth ------------------------------ From: mangan@Kodak.COM (Paul Mangan) Date: Thu, 19 Nov 92 08:13:59 EST Subject: Re: F-117 V. E-2 > From skunk-works-owner@ecn.purdue.edu Wed Nov 18 22:49:35 1992 > Subject: F-117 V. E-2 > To: "skunk-works" > Sender: skunk-works-owner@ecn.purdue.edu > Content-Length: 1899 > X-Lines: 32 > > Date sent: 18-NOV-1992 > > Hi all, > I really have a problem with the whole E-2 thing. If the E2 can pick > up the F117, which has the equivalent RCS of a "small Sparrow", then it is > probably picking up said sparrows regularly, you follow? As far as I know (and > I am a missileer, not a scientist or pilot) only the square wave radars, and > radar interferometry can pick the aircraft up at any real range. The only > report I heard was of a british scope dope picking one up just as it flew over > his van. This is to be expected. The E2 is not that great a package. It can > support a carrier air wing out to the range of the best carrier based weapons > or about 150 some odd miles. It doesn't have anywhere near the capability of > the E3 Sentry or the E8 JStars aircraft. The Coasties have given theirs back ^^^^^^^^^^ Sees the F117 as an occaisional flicker on the screen. AW&ST says they put iron on the wings to be seen in USA or Friendly countries. The turns are the biggest problem but straight and level from the front is no problem. The F117s were based in Turkey along with some F111s the primary group of 15s, 16s were in Saudi. Navy types were in the gulf and the Red Sea. The E2s were at an angle to the F117s that would allow alittle better observance. The E3s were out of Riiad (sp?) and would go up in a group of as many as 5 They would be refueled in the air and stay on station up to 16 hours. They were the main defense and and also used for target support. They are well known for there support (CAPS) of our F15s in the multiple shootdowns of Iraqi fighters. 2 F15s took on 6 Iraqi aircraft shooting down 4 and damaging the other 2. The AWACS guided them in with AWACS radar and then the F15s took care of the rest. It would not be unheard of for the AWACS to support the F117s on their missions. An AWACS for the EYES and the F117 for the STING. > because they weren't good enough. They now use the Air Force for the same job. > > Please keep in mind that as an Air Force officer, I have some small > prejudices. I have however spoken to the ops officer for the 37th Fighter Wing > (the F117 guys) about the strikes on Baghdad so I have some small knowledge. I > have also spent some time with the ops officer for the 462nd Fighter Sqdn (the > F4G's) and he told me his version. I am not speaking as a represntative of my > Air Force, just a wacko Skunker. 'Nuff said. > Cheers, > > Mike > *-----------------------------------------------------------------------------* > | Mike Cancellier, Lt, USAF ICBM Net: 34 06 24 N 117 48 21 W | > | CVALJ000@CSUPomona.edu or | > | Cal Poly Pomona Geography Dept. 47 55 31 N 97 01 57 W | > | Technical Specialist (Reply in 30 minutes, guaranteed!) | > | (714) 869-3590 Missileer in Waiting | > *-----------------------------------------------------------------------------* > > ------------------------------ From: "Philip R. Moyer" Date: Thu, 19 Nov 92 09:23:06 -0500 Subject: Re: F-117 V. E-2 >Some limited information on the TR3A may be found in various editions >of AvLeak, er, AvWeek. I don't get it so I have no references to give. The articles you refer to are in AW&ST, June 10, 1991, page 20. The first is entitled "Triangular Recon Aircraft May Be Supporting F-117A" and the second is entitled "TR-3A Evolved From Classified Prototypes, Based on Tactical Penetrator Concept". Both articles are authored by Bill Scott. Cheers, Phil ------------------------------ From: Geoff.Miller@Corp.Sun.COM (Geoff Miller) Date: Thu, 19 Nov 92 09:36:08 PST Subject: Re: F-117 V. E-2 mangan@Kodak.COM writes: >AW&ST says they put iron on the wings to be seen in USA or Friendly >countries. Iron on the wings??? I thought that radar reflectors were attached to the sides of the fuselage when needed, and removed for combat. In fact, I have an F-117 poster in my office, and the pattern of bolt-holes at the attachment point for the left-hand radar reflector is visible just aft of the national insignia. (I've seen photographs of these refelectors in either AvLeak or Koku-Fan, so I know where they're attached.) >The F117s were based in Turkey along with some F111s the primary group of >15s, 16s were in Saudi. This is the first mention I've seen of F-117s being based in Turkey. I'm positive that I read that they were based in Saudi Arabia. Regards, Geoff ------------------------------ From: larry@ichips.intel.com Date: Thu, 19 Nov 1992 10:02:38 -0800 Subject: Re: Copying Articles On Wed, 18 Nov 1992 10:32:51 -0800 Larry said: >T Velazquez writes: >> The following is an article that appears in the November 1992 issue of >>Air Force Magazine. > >Thanks for sharing this! In my opinion, this is what this mail list is all >about! Nick responded: >I'm probably being overly paranoid or formal or something, but the >(presumably unauthorized) copying of that much (presumably) copyrighted >material makes me nervous. I'm more comfortable with short excerpts and >enthusiastic recommendations that we all find the original issue and >read it. > >Just a thought, I know it's a pain, but, I agree that we need to adhere to copyright as well. I have had several private e-mail discussions on this. What I was referring to above was the researching or sharing of information, not the duplication of articles (unless those articles aren't copyrighted). Not all of us have access to the information, and some of the older sources are no longer available, so if people run across good historical or technical information, then I encourage people to take the time to share the facts from the article without copying it. You should still, of course, mention the sources. One of my private e-mail discussions on this subject has been helpful. The subject was an earlier article I had copied: Other skunker: >It's perfectly legal to reprint *excerpts* of copyrighted material for >discussion or review purposes -- the only prohibition is against copying >the piece in its entirety. Me: >So I could have kept some large percentage of the original intact? Other skunker: >Yup. Of course, precisely how much depends on your own judgment. The >point is that the intent should be to supply portions of the original for >discussion purposes, not to simply omit a single word in order to comply >with letter of the law but not the spirit. Now, I don't think that this other skunker is a lawyer, but he sounds 'familiar' with this issue. Any more comments? Larry ------------------------------ From: mike@percy.rain.com (Michael Heggen) Date: Thu, 19 Nov 1992 11:19:52 -0800 (PST) Subject: Re: Copying Articles larry@ichips.intel.com writes: > > One of my private e-mail discussions on this subject has been helpful. The > subject was an earlier article I had copied: > > Other skunker: > >It's perfectly legal to reprint *excerpts* of copyrighted material for > >discussion or review purposes -- the only prohibition is against copying > >the piece in its entirety. > > Me: > >So I could have kept some large percentage of the original intact? > > Other skunker: > >Yup. Of course, precisely how much depends on your own judgment. The > >point is that the intent should be to supply portions of the original for > >discussion purposes, not to simply omit a single word in order to comply > >with letter of the law but not the spirit. > > Now, I don't think that this other skunker is a lawyer, but he sounds > 'familiar' with this issue. Any more comments? While I am not a lawyer, either, I have had some experience with copyright law during my time working for Kinko's Copies (BTW, I do not speak for Kinko's, only for me -- don't work for 'em anymore, anyway). What you two were discussing is the so-called "Fair Use" clause of the copyright law. This is an extremely fuzzy area that Kinko's was sued over (won't go into that here). The gist of the Fair Use clause is that copyrighted material may be reproduced without permission in limited quantities as long as the work is not being reproduced in its entirety and (here's the important part) the purpose of the reproduction is for educational or critical purposes (as well as a few other purposes that slip my memory). As mentioned previously, I think the key issue here is intent. The intent of placing copyrighted material in this mailing list is not to avoid payment of royalties to the author, but to discuss and criticize the material. Correct me if I am wrong, but the article that was placed was, in fact, an excerpt, and not the article in its entirety, right? Further, althouhg there are a few hundred (?) people who read this mailing list, it is a pretty small number. - -- Michael Heggen "An expert is a person who avoids the small errors while sweeping on to the grand fallacy." --Weinberg's Corollary to Murphy's Computer Law ------------------------------ From: mangan@Kodak.COM (Paul Mangan) Date: Thu, 19 Nov 92 14:55:23 EST Subject: Re: F-117 V. E-2 > > > > > mangan@Kodak.COM writes: > > > >AW&ST says they put iron on the wings to be seen in USA or Friendly > >countries. > > Iron on the wings??? I thought that radar reflectors were attached to > the sides of the fuselage when needed, and re Iron is a quote, from the National Warplane Museum show at Geneseo,NY. They did a flyby there and an AF spokesman said that that is how they were able to be seen here to get along with commercial aircraft. It went something like " ...we bolt on 3 or 4 bars of iron to each wing to help..." Perhaps disinformation??? I'll try to keep my info to what is in the public domain from now on. > In fact, >I have an F-117 poster in my office, and the pattern of bolt-holes at And I have an actual photograph (no tail number but GRIFISS on the tail along with a large TR 37 FW & near the cockpit Capt. Greg Sembower) but that doesn't mean all machines are alike. Don't misunderstand ... no flames here just additional info. > the attachment point for the left-hand radar reflector is visible just > aft of the national insignia. (I've seen photographs of these refelectors > in either AvLeak or Koku-Fan, so I know where they're attached.) ^^^^^^^^ Me Too! > > > >The F117s were based in Turkey along with some F111s the primary group of > >15s, 16s were in Saudi. > > This is the first mention I've seen of F-117s being based in Turkey. I'm > positive that I read that they were based in Saudi Arabia. The ABC or CNN news were the ones that gave out the Turkey info and I agree that the only "written" info I've seen is for Khamis Mushait Air Base in Saudi and supposedly the 37th deployed their 415th TFS there. So I can't prove the ABC or CNN stuff and I am only being a reflection of that info. My son was there and I watched 3 TVs at a time for awhile. Quite often emotions got in the way of fact or disinformation, and I didn't tape record everything. > ------------------------------ From: Rick Lafford Date: Thu, 19 Nov 92 16:25:59 EST Subject: Re: F-117 V. E-2 >harle@jablab.gatech.edu (Mark R. Johnson) said: >I know I don't know what I'm talking about. Nothing wrong with dialog besides, how many of us know what we're talking about hmmmm. >However, it was mentioned >earlier that the F117 is not radar invisible from all sides - just >those that count (i.e. primarilly the front). It is also my understanding >that most of the radar evading ability comes from angular reflection >of tracking radar away from the source. Finally, it was also mentioned >that it had been decided that F117's are visible to radar from the rear. I'm not sure I'd go out on a limb to accept this. The F-117's radar signature is dramatically effected by many many things. Speed, bearing to the emitter, configuration of the aircraft, turning or straight, emitter type, distance to the emitter. It is not a safe assumption that the F-117 will fly a mission configuration straight to the target and over any radar sites that just happen to have been conviently placed between the countries borders and the target. If you will accept the assumption that the pilot might try to fly around the major radar installations then one would have to assume the the sides of the aircraft were also quite good at absorbing/deflecting EMR. >My suggestion is that the F117 is most visible from above and below, >as it is from these angles that it reveils the largest aspect, and >contains the slightest sloping surfaces. If this is the case, I >would assume that the E-2's would have a grand vantage point if >they track from high altitudes (i.e. significantly higher than the >F117 standard operational altitudes). Figure the E-2 at 30,000' and the F-117 at 500' - 1000' during ingress. Given a distance to the E-2 of 100 miles or greater, I'll leave the aspect angles (look down) to your calculations as I hate higher math. I think you'll find that the look-down component is quite negligable with much of any reflection lost in the ground clutter. Obviously, an F-117 going right overhead has a sizable reflection both from the distance and aspect factors but... this might be a case of him (the F-117 pilot) having you right where he wants you ;-). >It this is all true (though it probably is not), then the F117 would >have a great deal of trouble against an opponent with AWACS or similar >capability. However, it is a benefit for the tacticians who very much >would like to keep track of the F117's as they fly their missions... Your opponents AWACs does present a problem particularly if your target happens to be near his orbit. But the F-117 is not a Lone Ranger. A typical strike package is going to give the AWACS lots to look at and probably lots of screen fuzz to boot. You can image that agressive movements would be made to move the AWACS track off the F-117's ingress track. Typical Allied doctrine would move the AWACS somewhere around 25- 300 miles behind the lines and out of any danger from opposing fighters. This puts the AWACS back to the low aspect angle problem again, one where the F-117's reflection might be small enough to avoid detection. >From: I am the NRA said: >(Unrelated, as to F117 self defense ability: saw one at Omaha, two years >ago(?). Someone asked the driver if he had any self defense capability, the >response, roughly: > We have some special stuff. We can look after ourselves. >Was he "disinforming"? Dunno.) Beyond active and passive IR, radar countermeasures and possibly a decoy system, I strongly suspect that the F-117's primary defense tactic is much like a Boomers... to become a hole in the ocean (of air). >Paul Mangan said: >the F15s took care of the rest. It would not be unheard of for the AWACS >to support the F117s on their missions. An AWACS for the EYES and the >F117 for the STING. Remember that the F-117 has no active radar capability but it does have a very nice datalink. The E-3 (or SOMETHING more secret ;-)), with the big pictured, can download data to the F-117. Between this data and the input from onboard passive systems, the F-117 pilot can develop a situational awareness without exposing himself with active emissions. BTW - the radar reflectors attached to the flanks of the F-117 during non-combat operations are called 'Warts'. The provide a very important function. If a F-117 loses his transponder and voice transmitter capability, he would be essentially invisible to conventional ATC radar and he would present a great hazard in the normal European or US congested ATC environment. The pilot would have to follow IFR loss of communications procedures and a corridor opened up for him based on his flight plan and ETA. The situation becomes much nicer (and safer) if ATC can at least see him on radar. At least then they don't have to close the airbast Regards, Rick - ---------------------------------------------------------------------------- Rick Lafford |"Mame, we're sorry to report the disappearance of Eastman Kodak Co. | your husband. His F-117 just disappeared from lafford@serum.kodak.com | our scopes shortly after takeoff." ============================================================================ ------------------------------ From: Geoff.Miller@Corp.Sun.COM (Geoff Miller) Date: Thu, 19 Nov 92 13:53:37 PST Subject: Re: F-117 V. E-2 >Iron is a quote, from the National Warplane Museum show at Geneseo,NY. >They did a flyby there and an AF spokesman said that that is how they >were able to be seen here to get along with commercial aircraft. It went >something like " ...we bolt on 3 or 4 bars of iron to each wing to help..." >Perhaps disinformation??? Sounds like it was meant as a joke. I can't imagine that bolting iron bars to the wings of an airplane would have a very positive effect, aerodynamically speaking. :) >And I have an actual photograph (no tail number but GRIFISS on the tail >along with a large TR 37 FW & near the cockpit Capt. Greg Sembower) but >that doesn't mean all machines are alike. True. It's surprising that "Griffiss" would be painted on an F-117. That's an Air Force base in upstate New York, as I recall. All the F-117s are based at Holloman AFB in New Mexico, and at Tonopah before that. Maybe it was a PR thing. >Don't misunderstand ... no flames here just additional info. No problem! Regards, Geoff ------------------------------ From: davem@ee.ubc.ca (david michelson) Date: Thu, 19 Nov 92 15:30:25 PST Subject: Re: F-117 V. E-2 > >AW&ST says they put iron on the wings to be seen in USA or Friendly > >countries. > > Iron on the wings??? I thought that radar reflectors were attached to > the sides of the fuselage when needed, and removed for combat. In fact, > I have an F-117 poster in my office, and the pattern of bolt-holes at > the attachment point for the left-hand radar reflector is visible just > aft of the national insignia. (I've seen photographs of these refelectors > in either AvLeak or Koku-Fan, so I know where they're attached.) > > Regards, > Geoff I assume that the F-117 uses some sort of conformal retrodirective (Van Atta) array for RCS enhancement. I just can't imagine them using corner reflectors as some have alluded to on the list recently. Of course,conformal Van Atta arrays are frequency selective by their nature but most ATC primary radars are clustered around in L-band anayway... Just some idle thoughts... Please feel free to correct and comment :-) - -- Dave Michelson davem@ee.ubc.ca ------------------------------ From: bruce@pages.com (Bruce Henderson) Date: Thu, 19 Nov 92 16:32:07 -0800 Subject: Stealth VS Radar It has been my experience that the F-117 along with some other low RCS aircraft are especially prone to some of the frequencies use by Synthetic Aperture Radar. The SAR system that I had the job of working with was able to get about 20% normal energy. (normal energy being what a non-stealth aircraft of the same size would yield). While this makes it harder to pick it out, it is still possible to do enough imaging to tell the kind of aircraft it is to within a reasonable margin of error. I'm not sure if it has to do with the frequency, the method of broadcast or the nature of SAR. Bruce PS. sorry I can't be more specific.... but I just can't. ------------------------------ From: dnadams@nyx.cs.du.edu (Dean Adams) Date: Thu, 19 Nov 92 23:20:02 MST Subject: Re: F-117 Article (1-3) larry@ichips.intel.com writes: >T Velazquez writes: >> The following is an article that appears in the November 1992 >> issue of Air Force Magazine. >Thanks for sharing this! In my opinion, this is what this mail >list is all about! Ditto! My thinking EXACTLY... >What is neat about this, is that this piece has the same flavor >as The OXCART History has, at least for me. Which of course was one of the "mother of all SW postings". :-) >Several key points I'd like to point out. >> Despite the F-117's public image as the most modern of >>warplanes, the radar-evading aircraft had its technical origins late >>in the administration of President Dwight D. Eisenhower. Hula-Hoops >>were in vogue when Lockheed's Kelly Johnson and Ben Rich turned their >>attention to improving on the U-2 spyplane then flying reconnaissance >>patrols over the Soviet Union. >This seems to echo what the OXCART History said as well - that stealth >began back in the 50's. See page 2 of The OXCART History. Yep... At least the concept of low-RCS was very much in mind when the U-2 follow-on proposals were under study, and with everyone working on the A-12. Here is a short note from Lockheed Horizons on the F-117s beginnings: Today's Stealth Fighter traces its roots to 1974 when DARPA asked five major military aircraft manufacturers to study the potential for developing fighter aircraft with significantly reduced radar detectability. Having not produced a fighter since the F-104, Lockheed was not invited to participate. By early 1975, word of the unclassified DARPA project reached interested ears at Lockheed ADP. This small section of Lockheed's Burbank plant had continually advanced aviation technology with products like the F-104, U-2, and SR-71, although many of it's developments remained largely secret. Ben Rich, then deputy to Clarence "Kelly" Johnson, knew that Lockheed's "stealth" experience on the SR-71 gave him the means to deliver exactly what DARPA was seeking. Rich got Johnson to obtain a letter from the CIA granting permission to discuss the SR-71's low observable characteristics in order to petition for Lockheed to be included in the project. >> From this point forward, stealth development went deep into >>"the black," or the classified world. The vehicle was the Have Blue ok >>program, Here is Lockheed's version: Under the project designation Have Blue, pole-mounted radar signature models were tested, and in April 1976 Lockheed was declared the winner of the DARPA competition. Lockheed's results exhibited such a breakthrough that the unclassified DARPA project immediately became black - deep black! Security was tightened by transferring administration of the program from the largely civillian-staffed DARPA to the Special Projects Office of the Air Force. >>which produced stealth technology demonstrators. >The plurality of 'demonstrators' is the key word. >Not the first time I've heard this. Well, I suppose that refers to the two flying Have Blue birds, plus the various static RCS test articles that both preceeded and followed them. Then starting on June 18, 1981 came the five F-117 flight test vehicles - -dean ------------------------------ From: dnadams@nyx.cs.du.edu (Dean Adams) Date: Thu, 19 Nov 92 23:21:00 MST Subject: Re: F-117 Article (1-3) upp@comm.mot.com (Steve Upp) writes: >> "Such a radical technology had its doubters. The model above >>was bombarded with radar beams without result. Once, a skeptical > ^^^^^^^^^^^^^^ >What the heck does 'without result' mean here? It means there was not a significant reflection. a.k.a. "Stealth". >Do you really believe that the airframe was able to absorb or >deflect 100% of the radar beam? Give me a break... Remember one thing, this was a test article. Not an actual airframe. >This kind of claim is an absolute joke, Maybe, maybe NOT. I see no reason to totally discount it. >I would assume many people who read this list heard the reports of >F-117's being observable over Iraq during the war. They certainly were not "observed" over BAGHDAD! >I had the opportunity to talk with an individual who flew many missions >during the war aboard an E-2 (a Navy carrier based radar aircraft) . >He confirmed the press reports that said that they were able to track >the airplane without difficulty during its entire mission. I have to be highly skeptical of that, especially in reference to "entire mission". There ARE times that an F-117 can be tracked, such as with certain antennas deployed or radar reflectors attached. >I'm trying to remember now, but I believe that during the first night of the >air battle the F-117's were accompanied by radar jamming aircraft (Wild >Weasles). Wild Weasles are not jammers. They carry HARM anti-radiation missiles and are charged with the mission of taking out anti-aircraft radar and SAM sites. During the first night of the war, these aircraft would be at their busiest, knocking out all of the Iraqi air defense assets. They "accompanied" the F-117 only as a very active participant of the opening campaign... *NO* other manned aircraft besides the F-117 flew into Baghdad. >That says quite a bit about the confidence the Air Force had >in their ability to avoid enemy radar! Yes, that confidence was very high. >After all the jammers could have been used to escort more of the >known 'non-stealthy' missions that instead were left more vulnerable >because they had to escort the 'stealthy' aircraft. WRONG. The EA-6B Prowler and EF-111 Ravens were all quite busy escorting strike packages of non stealthy aircraft... NOT F-117s. >> A small team, working free from public scrutiny, brought stealth from >>the laboratory to operational use, which many said couldn't be done." >There is a definite downside to this. The lack of public scrutiny could >also mean that there is less risk that their funding will get cut because >the system doesn't work as well as the price tag suggests. I would certainly agree that many black programs should be open to more "public scrutiny", but i'm afraid you are giving the F-117 undeserved criticism in this case... ------------------------------ From: dnadams@nyx.cs.du.edu (Dean Adams) Date: Thu, 19 Nov 92 23:21:41 MST Subject: Re: F-117 Article (1-3) wb9omc@ecn.purdue.edu (Duane P Mantick) writes: >I can think of one *possible* VERY good reason to send Weasels in with >the F117a's (one reasons with several clauses, that is....) Well, I can think of one major *critical* reason NOT to. :-) The F-117s is stealthy. A Wild Weasel F-4G very much is *not*. Combining a flight of stealth and non-stealth aircraft on a combat mission will totally eliminate the advantage of the stealth ships. Therefore, such a combination would NEVER be employed (in combat). What happens is you have a *seperate* flight of 117s and F-4Gs, each with their own flight plan and designated targets... ------------------------------ From: dnadams@nyx.cs.du.edu (Dean Adams) Date: Thu, 19 Nov 92 23:22:57 MST Subject: Re: F-117 Article (1-3) Nick Laflamme <@VM.CC.PURDUE.EDU:NLAFLAMM@IRISHVMA> writes: >>Thanks for sharing this! In my opinion, this is what this mail >>list is all about! Once again, I totally agree. >I'm probably being overly paranoid or formal or something, but the >(presumably unauthorized) copying of that much (presumably) copyrighted >material makes me nervous. Well, there is one obvious solution to anyone that is "nervous"... :-) >I'm more comfortable with short excerpts and enthusiastic >recommendations that we all find the original issue and read it. I am MUCH more comfortable with ALL the available information. It is not always so easy for everyone to "find the original issue". I for one have been checking around for that very magazine, but have not been able to obtain a copy. I am VERY grateful for the contribution to the list. mike@percy.rain.com (Michael Heggen) writes: >... >As mentioned previously, I think the key issue here is intent. The >intent of placing copyrighted material in this mailing list is >not to avoid payment of royalties to the author, but to discuss and >criticize the material. Correct me if I am wrong, but the article >that was placed was, in fact, an excerpt, and not the article in its >entirety, right? Further, althouhg there are a few hundred (?) people >who read this mailing list, it is a pretty small number. "intent" is the factor that makes all the difference to ME at least. Nobody posts information here for the purpose of "profiting" or to derive some sort of illicit gain at the expense of an author of a copyrighted work. We are here to freely EXCHANGE INFORMATION and discuss it. I for one feel MUCH better having as complete an account of such material as possible for this purpose. Nobody is trying to "defraud" any author of their work, and I do not see how any "loss" could be attributed by having an article posted to this group. I looked quite a bit to find that AFM issue, and if I find it I will STILL purchase a copy. BUT, many people will have NO way to get a copy of some articles or other information. Posting such information is therefore the only means of getting it for some. The only thing that makes me "nervous" is thinking that someone might WITHHOLD sharing such an article because of some "paranoia"... When people become afraid of sharing information, it's pretty much time to close up shop and go home. - -dean ------------------------------ From: dnadams@nyx.cs.du.edu (Dean Adams) Date: Fri, 20 Nov 92 04:28:51 MST Subject: SR-71 Development I recently picked up a nice new reprint of a couple interesting articles which i'm quite sure some of you saw a long time ago. But, for the benefit of others i'll go ahead and excerpt some of the best stuff. (Originally from: "Lockheed Horizons", Winter 1981) DEVELOPMENT OF THE LOCKHEED SR-71 BLACKBIRD by Clarence L. Johnson This paper has been prepared by the writer to record the development history of the Lockheed SR-71 reconnaissance airplane. In my capacity as manager of Lockheed's Advanced Development Division (more commonly known as the "Skunk Works"), I supervised the design, testing, and construction of the aircraft referred to until my partial retirement five years ago. Because of the very tight security on all phases of the program, there are very few people who were ever aware aspects of the so-called "Blackbird" program. Fortunately, I kept as complete a log on the subject as one individual could on a program that involved thousands of people, over three hundred subcontractors and partners, plus a very select group of Air Force and Central Intelligence Agency people. There are still many classified aspects of the design and operation of the Blackbirds by my avoiding these, I have been informed that I can still publish many interesting things about the program. In order to tell the SR-71 story, I must draw heavily on the data derived on two prior Skunk Works programs -- the first Mach 3-plus reconnaissance type, known by our design number as the A-12 and the YF-12A interceptor, which President Lyndon Johnson announced publicly 1 March 1964. He announced the SR-71 on 24 July of the same year. BACKGROUND FOR DEVELOPMENT [..] Starting in 1956, we made many studies and tests to improve the survivability of the U-2 by attempting to fly higher and faster as well as reducing its radar cross-section and providing both infrared and radar jamming gear. Very little gains were forthcoming except in cruise altitude so we took up studies of other designs. We studied the use of new fuels such as boron slurries and liquid hydrogen. The latter was carried into the early manufacturing phase because it was possible to produce an aircraft with cruising altitudes well over 100,000 feet at Mach numbers of 2.5. This design was scrapped, however, because of the terrible logistic problem of providing fuel in the field. GETTING A GRASP OF THE PROBLEM [..] Special attention had to be given to the crew escape system to allow safe ejection from the aircraft over a speed and altitude range of zero MPH at sea level to Mach numbers up to 4.0 at over 100,000 feet. [..] << Note: that statement about the *ejection* system has seemed to me a << likely source for some labeling the SR a "Mach 4+, 100K ft+" aircraft. << The fact is, an ejection seat should be rated for margins ABOVE those << which you expect to encounter in normal flight... HOW THE BLACKBIRD PROGRAM GOT STARTED In the time period of 21 April 1958 through 1 September 1959, I made a series of proposals for Mach 3-plus reconnaissance aircraft to Mr. Richard Bissell of the CIA and to the U.S. Air Force. These airplanes were designated in the Skunk Works by design numbers of A-1 through A-12. We were evaluated against some very interesting designs by the General Dynamics Corporation and a Navy in-house design. This latter concept was proposed as a ramjet-powered rubber inflatable machine, initially carried to altitude by a balloon and then rocket boosted to a speed where the ramjets could produce thrust. Our studies on this aircraft rapidly proved it to be totally unfeasible. Convair's proposals were much more serious, starting out with a ramjet powered Mach 4 aircraft to be carried aloft by a B-58 and launched at supersonic speeds. Unfortunately, the B-58 could not go supersonic with the bird in place, and even if it could, the survivability of the piloted vehicle would be very questionable due to the probability of ramjet blow-out in maneuvers. At the time of this proposal the total flight time for the Marquardt ramjet was not over 7 hours, and this time was obtained mainly on a ramjet text vehicle for the Boeing Bomarc missile. Known as the X-7, this test vehicle was built and operated by the Lockheed Skunk Works! The final Convair proposal, known as the Kingfisher, was eliminated by Air Force and Department of Defense technical experts, who were given the job of evaluating all designs. On 29 August 1959 our A-12 design was declared the winner and Mr. Bissell gave us a limited go-ahead for a four-month period to conduct tests on certain models and to build a full-scale mock-up. On 30 January 1960 we were given a full go-ahead on the design, manufacturing, and testing of 12 aircraft. The first one flew on 26 April 1962. The next version of the aircraft, an Air Defense long-range fighter, was discussed with General Hal Estes in Washington, D.C. on 16 and 17 March 1960. [..] It was on 27 and 28 December 1962 that we were finally put on contract to build the first group of six SR-71 aircraft. BASIC DESIGN FEATURES [..] AERODYNAMIC TESTING [..] A full-scale fuel system test rig was used to test fuel feed capability for various flight attitudes. By far the most tunnel time was spent optimizing the nacelle inlets, bleed designs, and the ejector. A quarter-scale model was built on which 250,000 pressure readings were taken. With engines located half way out on the wing span, we were very concerned with the very high yawing moment that would develop should an inlet stall. We therefore installed accelerometers in the fuselage that immediately sensed the yaw rate and commanded the rudder booster to apply 9 degrees of correction within a time period of 0.15 seconds. This device worked so well that our test pilots very often couldn't tell whether the right or left engine blew out. They knew they had a blowout, of course, by the bad buffeting that occurred with a "popped shock". Subsequently, an automatic restart device was developed which keeps this engine-out time to a very short period. POWERPLANT DEVELOPMENT (here there is another article inserted) J58/SR-71 PROPULSION INTEGRATION, (OR) THE GREAT ADVENTURE INTO THE TECHNICAL UNKNOWN by William H. Brown, Pratt & Whitney Aircraft Group [...seven page article which I don't have time to type in :( ] STRUCTURAL PROBLEMS [..] Having made the basic materials choice [titanium], we decided to build two test units to see if we could reduce our research to practice. The first was to study thermal effects on our large titanium wing panels. We heated up this element with the computed heat flux that we would encounter in flight. The sample warped into a totally unacceptable shape. To solve this problem we put chordwise corrugations in the outer skins and reran the tests very satisfactorily. [..] I was accused of trying to make a 1932 Ford Trimotor go Mach 3 but the concept worked fine. The second test unit was the forward fuselage and cockpit, which had over 6,000 parts in it of high curvature, thin gages, and the canopy with its complexity. This element was tested in an oven where we could determine thermal effects and develop cockpit cooling systems. [..] For an outfit that hates paperwork, we really deluged ourselves with it. Having made over 13 million titanium parts to date we can trace the history of all but the first few parts back to the mill pour and for about the last 10 million of them even the direction of the grain in the sheet from which the part was cut has been recorded. FLUID SYSTEMS [..] THE FLIGHT TEST PHASE The first flight of the A-12 took place 26 April 1962 or thirty months after we were given a limited go-ahead on 1 September 1959. We had to fly with P&W J75 engines until the J58 engine became available in January 1963. [..] OPERATIONAL COMMENTS The SR-71 first flew 23 December 1964. It was in service with the Strategic Air Command a year later. In-flight refueling from KC-135s turned out to be very routine. Over 18,000 such refuelings have been made to date by all versions of the Blackbirds and they have exceeded Mach 3 over 11,000 times. [Note: this is as of 1981/2] - --- The article ends with a bio of Kelly Johnson. ------------------------------ End of Skunk Works Digest V2 #10 ******************************** To subscribe to skunk-works-digest, send the command: subscribe skunk-works-digest in the body of a message to "listserv@harbor.ecn.purdue.edu". If you want to subscribe something other than the account the mail is coming from, such as a local redistribution list, then append that address to the "subscribe" command; for example, to subscribe "local-skunk-works": subscribe skunk-works-digest local-skunk-works@your.domain.net A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace all instances of "skunk-works-digest" in the commands above with "skunk-works". Back issues are available for anonymous FTP from harbor.ecn.purdue.edu, in /pub/skunk-works/digest/vNN.nMMM (where "NN" is the volume number, and "MMM" is the issue number).