From: skunk-works-digest-owner@mail.orst.edu To: skunk-works-digest@mail.orst.edu Subject: Skunk Works Digest V5 #641 Reply-To: skunk-works-digest@mail.orst.edu Errors-To: skunk-works-digest-owner@mail.orst.edu Precedence: Skunk Works Digest Friday, 29 March 1996 Volume 05 : Number 641 In this issue: re: Canards (verbose) Mil Spec. canards Re: A-12 0-person A-12s re: Mil Spec. canards Sender: owner-skunk-works Re: Canards Canards Re: Mil Spec. canards re: Mil Spec. canards Re: Canards dranacs PS dranacs RAM... (No, not the computer type).... Re: PS dranacs Re: PS dranacs Re: PS dranacs Re: Sonic Boom Carrying Distance Re: PS dranacs Re: Sonic Boom Carrying Distance USAF "New World Vistas" Technology Forecast Bill Park...... re: Bill Park...... "Spikes" and "fuzzball" 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: ahanley@usace.mil Date: Mon, 25 Mar 96 8:50:43  Subject: re: Canards (verbose) O.K. Charles, you make a good case for upsetting Burt Rutan in civil aviation. what do you think, though, of canards in the military field (i.e Grippen, Rafale, etc.) where you do get to put the fuel in the fuselage. P.S. You call that verbose? Have you ever read some of mine when I get going? Now THAT's Verbose! Art Hanley Not only do my employers not endorse the views above, they aren't even aware of them. ------------------------------ From: Charles_E._Smith.wbst200@xerox.com Date: Mon, 25 Mar 1996 10:00:07 PST Subject: Mil Spec. canards They are more than a little prone to inertia coupling. If you pull up and roll at the same time you might end up in going backwards! Once again, the canard planform plots to defeat itself. ------------------------------ From: larry@ichips.intel.com Date: Mon, 25 Mar 1996 10:08:22 -0800 Subject: Re: A-12 >Anyone got any info on the Lockheed A-12, I seem to remember reading that it >was a single-seat SR-71. Can anyone confirm/deny this. This is Skunk Works 101, but that's OK. It's more like the SR-71 was a two-seat version of the A-12 which also had its own two seat version, one of which was a trainer and the other launched the 0-seat version of the A-12 known as the D-21A. Lorenzo ------------------------------ From: larry@ichips.intel.com Date: Mon, 25 Mar 1996 10:40:00 -0800 Subject: 0-person A-12s This reminds me of a funny Groom Lake story that I learned at one of the MD-21 parties I attended at the Seattle Museum of Flight. Guys who were in the MD program told me this story. It seems that during the MD program at the Test Range, there was this little person that used to visit the MD program guys from time to time during off periods. They got to know him fairly well. Well, the MD guys used to like to joke around with people on some of the other test programs. One day, there was a gathering near the MD's hangar of a bunch of people who worked on several of the test programs at the site. Waiting around one day, this little fellow and the MD program guys had come up with an idea for a great spoof and they formulated a plan for some time in the future when the situation presented itself, where they could pull this prank off. Well, the situation was clearly the right time. Near the end of a waiting period, close to when the MD was supposed to fly, the little person excused himself, indicating that he had to go and suit up. Now, since the people in this other test program had seen the MD configuration before, the looks on their faces changed to one of puzzlement and amazement at the implication. Yes, the members of the MD test program immediately confirmed, answering their guests astonished looks. This little fellow was the test pilot of the D-21! Evidently, the members of the other test program believed this just long enough for everyone to enjoy a good laugh! Larry ------------------------------ From: ahanley@usace.mil Date: Mon, 25 Mar 96 10:18:41  Subject: re: Mil Spec. canards Charles, may we then infer that your idea of the perfect aircraft design would probably not be a canard-equipped B-2? Art Hanley Despite all appearances to the Contrary, my employers have nothing to do with any of the above ------------------------------ From: MICHAEL WEATHERSBY Date: Mon, 25 Mar 1996 13:32:04 -0500 Subject: Sender: owner-skunk-works How about a slight change of pace... Does anyone know how far a sonic boom can be heard with fair conditions on a clear, warm day... There was discussion about the "boom" heard in California that shook a couple of towns or something and the explanation was Navy exercises over the Pacific with certain atmospheric conditions that allowed the sonic boom to be heard inland... With that in mind, I was watching the Nascar race in Darlington, S.C. ( approximately 80 miles from the coast but only about 40 miles from Shaw AFB) and during this race the announcers yelled something like "WHOA!! What was that!!" and you could slightly hear the echo of some kind of boom in the distance... They never did say anything else about it but I wondered if the F-16's from Shaw could be over the Atlantic (some 80 miles away) and maybe did the same thing that the Navy guys did over the Pacific??? Like I said before, it was a clear day with temps in the mid 70's. Is it possible that a sonic boom was heard from that distance over the sound of the cars on the track??? Just wondering... Mike Weathersby WEATHER@DHHS.STATE.SC.US ------------------------------ From: larry@ichips.intel.com Date: Mon, 25 Mar 1996 11:06:42 -0800 Subject: Re: Canards Let's bring this back to Skunky. Opinions about: 1. Winglets on Canards 2. Forward swept Canards 3. Both 1 and 2. ------------------------------ From: David Lednicer Date: Mon, 25 Mar 1996 14:05:23 -0800 (PST) Subject: Canards Yes, Chuck, canards are not the end-all and be-all. You forgot in your postings that their induced drag sucks because it is a nightmare to get all the circulation distributions to add up to an ellipse, and if you do, you end up with a wing carrying all of its lift way outboard. Obviously, this leads to big root bending moments and you can't put fuel out there to alleviate this, through inertial relief. Plus, propulsive efficiency can really suffer, if its a pusher, from all of the wakes you are throwing through the prop. Lastly, trying to add retractable landing gear is difficult - it wants to go where the fuel goes (the inboard wing/strake). I don't agree with you about canard "stalls". I have done a lot of aero work for Burt, I helped Beech fix the Starship and I helped fix the JetCruzer so that AASI could get it certified. A properly designed and built canard aircraft is totally incapable of "stalling", not matter what you do. The only way they could get the Starship POC to depart was to kick serious rudder at high alpha, stalling the winglet. This was fixed on the production aircraft, with vortex generators. On the other hand, an improperly designed or built canard aircraft can be dangerous, but the same holds true for conventional aircraft. Despite all canarad shortcomings, would 5000 sets of VariEze and Long EZ plans have been sold if their were conventional configuration aircraft?????? - ------------------------------------------------------------------- David Lednicer | "Applied Computational Fluid Dynamics" Analytical Methods, Inc. | email: dave@amiwest.com 2133 152nd Ave NE | tel: (206) 643-9090 Redmond, WA 98052 USA | fax: (206) 746-1299 ------------------------------ From: Brett Davidson Date: Tue, 26 Mar 1996 10:49:49 +1200 (NZST) Subject: Re: Mil Spec. canards On Mon, 25 Mar 1996 Charles_E._Smith.wbst200@xerox.com wrote: > They are more than a little prone to > inertia coupling. If you pull up and roll at the same > time you might end up in going backwards! > > Once again, the canard planform plots to defeat itself. > Hmmm reminds me of a line in an interview with an aircraft designer I once read: "The best place for a canard is on the other guy's plane!" - --Brett ------------------------------ From: Brett Davidson Date: Tue, 26 Mar 1996 10:51:31 +1200 (NZST) Subject: re: Mil Spec. canards On Mon, 25 Mar 1996 ahanley@usace.mil wrote: > Charles, may we then infer that your idea of the perfect aircraft design would > probably not be a canard-equipped B-2? > > Art Hanley Charles is going to love this - an illustration in Flight International a month or so back showed a MiG proposal for a stealth bomber... it looked like a canard-equipped B-2. Actually, to spoil a good joke, it was a blended wing-body with a lot of YF-23 in it. - --Brett ------------------------------ From: Brett Davidson Date: Tue, 26 Mar 1996 10:55:34 +1200 (NZST) Subject: Re: Canards On Mon, 25 Mar 1996 larry@ichips.intel.com wrote: > > Let's bring this back to Skunky. > > Opinions about: > 1. Winglets on Canards > 2. Forward swept Canards > 3. Both 1 and 2. How about flying canards? - --Brett ------------------------------ From: Charles_E._Smith.wbst200@xerox.com Date: Tue, 26 Mar 1996 04:09:00 PST Subject: dranacs Dave writes >A properly designed >and built canard aircraft is totally incapable of "stalling", not matter >What you do. Dave, I dissagree. The statement you make makes perfect sense aerodynamically, but could only be true if the airplane has zero mass. Just because the canard stalls, one cannot make the statement that the pitch will stop increasing. That would require a instantaneous change in pitch rate which would necessitate an infinite force (well, r X F, okay) to overcome the angular momentum of the aircraft. And as I tried to explain, but did a lousy job, turbulence and gusting can changes in alpha. This is usually only a problem at low velocities- but thats the problem area of the flight regime anyway. About the EZ`s. Now , Advance Scaled Composites is a pretty neat organization, full of wonderfully talented and dedicated individuals......... I`m not sure how old you are Dave, so you may or may not remember a lot of this. The VariEZ was as I remember, the first real foam and glass homebuilt. It was popular (and still is) more for the fact that you didn`t have to weld, mess around with Stitts or Ceconite and the performance was excellent. Up to the EZs, if you wanted a fast homebuilt you needed to be a great (and dedicated!) riveter and build something like an RV3 or go with the tiny KR2, and be a great gluer. To say the EZ was a success because it was a canard...... lets just say, when`s the last time you say a Vari Viggen? Which is a to me, a much neater A/C than the EZ`s. Everything else you say I agree with. I`m flight dynamics and you`re aerodynamics. I like aerodynamics but could never get into the black robes and dead chickens and Gregorian chants required when you guys go behind closed doors. And I`m allergic to incense and bat`s wings. Chuck ------------------------------ From: Charles_E._Smith.wbst200@xerox.com Date: Tue, 26 Mar 1996 10:54:26 PST Subject: PS dranacs Oh, forgot, Myth # 2 canard. A stalled canard does not push the nose up. Nope- It is still pushing up! Just not as hard, and with more drag. END OF SUBJECT We`re way off charter. Chuck ------------------------------ From: Ralph the Wonder Llama Date: Tue, 26 Mar 1996 15:16:13 -0600 (CST) Subject: RAM... (No, not the computer type).... With all this discussion of canards and 'magic shapes' of stealth aircraft, what sort of publicly known research has been done into radar absorbing materials, the other half of a stealth machine? And somewhat along those same lines, has there been any more information released on the 'avacado' skunky aircraft? (There was some talk on this one a while back - it appears to be a stealth A/C that has an 'avacado' like appendage, apparently for noise reduction). I think Popular Science had a short blurb on this aircraft some time ago... (admittedly not the best source, but skunkers read what they can get :) - - Michael ------------------------------ From: habu@why.net (habu) Date: Tue, 26 Mar 1996 15:53:59 -0800 Subject: Re: PS dranacs Charles_E._Smith.wbst200@xerox.com wrote: > END OF SUBJECT > We`re way off charter. > > Chuck Amen. ------------------------------ From: ahanley@usace.mil Date: Tue, 26 Mar 96 17:12:59  Subject: Re: PS dranacs Reply by : Art Hanley@IM@SPK Date : Tuesday, March 26, 1996 17:12:57 Reply to : , smtp@SPKSYS12@Servers[skunk-works@mail.orst.edu] Reply: Just to be difficult (I was actually enjoying the discussion)... Your attention is directed to the cover story of the March 25 Aviation Week "X-36 Rollout" How Agile Can Stealth be?" The subheading in the article is "Some features of stealthy designs can hurt agility. The X-36 may show how to overcome them." The X-36 sure looks like a canard aircraft to we of the uninitiated. The canards are supposedly there to overcome the forebody lift at high angles of attack and to destabilize the aircraft in pitch. I would say this qualifies as on-charter and I'd be curious regarding what those more knowledgeable than me think of MDD's design. Art Hanley In compliance with the Full Employment For Lawyers Act, I must state that the Above does not represent my employer's Views, only mine -------------------------- [Original Message] ------------------------- To : "Skunk Works" From : habu@why.net (habu) Subject : Re: PS dranacs Date : Tuesday, March 26, 1996 at 3:53:59 pm PST - ------------------------------------------------------------------------------ Charles_E._Smith.wbst200@xerox.com wrote: > END OF SUBJECT > We`re way off charter. > > Chuck Amen. ------------------------------ From: BaDge Date: Tue, 26 Mar 1996 20:34:43 -0500 (EST) Subject: Re: PS dranacs Hi gang, I've been stuck with my head in a book for a few weeks, OK, no wisecracks, but, wasn't there supposed to be a televised rollout this month of the new X plane? Gosh, I think I even reported it here, heh. Art's post about the X36 reminded me. Anyone have any .gif pics of it or anything? If I find one, I'll put it on my ftp site. regards, ________ BaDge ------------------------------ From: keller@eos.ncsu.edu Date: Wed, 27 Mar 96 08:50:27 EST Subject: Re: Sonic Boom Carrying Distance Michael Weathersby shaped the electrons to say... >How about a slight change of pace... >Does anyone know how far a sonic boom can be heard with fair >conditions on a clear, warm day... There was discussion about the >"boom" heard in California that shook a couple of towns or something >and the explanation was Navy exercises over the Pacific with certain >atmospheric conditions that allowed the sonic boom to be heard >inland... [deletia] No one has answered this publicly yet. I can toss out some first-hand experience here. In a former life while employed at a nuclear power plant about 50 miles west of Phoenix, Arizona we used to hear sonic booms regularly. The site was located between Luke AFB and the Luke gunnery range, so, given that Luke was (and I understand still is), the primary training base for F-15 and -16 drivers, presumably what we hearing were those, and maybe some T-38s. At the time I lived about thirty miles east of the plant site, and I never heard a sonic boom at home, admitedly in a popoulated area just to the west of Phoenix. Thus, apparently the booms carry less than thirty miles in the clear, dry, desert air. FWW: I've been enjoying the canards discussion, and do not consider it to be off-topic. I would enjoy hearing more about mil-spec canards. Yes, I've seen the X-36 article in this week's AvWeek, but haven't had time to read it carefully yet. Somebody (was it McD-D & Northrup?) had canards on their NATF proposal, didn't they? Paul Keller keller@eos.ncsu.edu ------------------------------ From: fmarkus@pipeline.com (Frank Markus) Date: Wed, 27 Mar 1996 09:47:14 -0500 Subject: Re: PS dranacs On Mar 26, 1996 20:34:43, 'BaDge ' wrote: >Hi gang, > >I've been stuck with my head in a book for a few weeks, OK, no >wisecracks, but, wasn't there supposed to be a televised rollout this >month of the new X plane? > >Gosh, I think I even reported it here, heh. > >Art's post about the X36 reminded me. Anyone have any .gif pics of it or >anything? > >If I find one, I'll put it on my ftp site. > > >regards, >________ >BaDge > > There is a photograph of the X-36 on the cover of the current Aviation Week. There are more photographs and a three-view line drawing of the aircraft in an article inside. The X-36 is not a full-size manned aircraft. Rather, it is a 28% scale model of a "notional" manned fighter. Two have been built. I have to wonder whether it is a cover for other "real" aircraft in the black world. I would not be the first time. ------------------------------ From: Charles_E._Smith.wbst200@xerox.com Date: Wed, 27 Mar 1996 10:11:43 PST Subject: Re: Sonic Boom Carrying Distance You should be able to get a reasonable approximation using D`Lambert`s wave equation. The only fly in the ointment is putting the adiabatic lapse rate into the geometry. (The speed of sound decreases as you go up, then increases again, but seems the assumption of constant temp at sea-level would be OK) Also, the size of the disturbance has a lot to do with it. The difference in pressure on either side of the wave depends on Mach number, and some other goofy stuff. Chuck ------------------------------ From: CULLY@svr81trw.kee.aetc.af.mil (CULLY, George Mr) Date: 27 Mar 96 13:58:26 EST Subject: USAF "New World Vistas" Technology Forecast For those who have been following the latest USAF technology forecasting effort, "New World Vistas," the Scientific Advisory Board is offering a copy of the 90-page summary for the asking by e-mailing to or writing HQ USAF/SB, 1180 Air Force Pentagon, Washington DC 20330-1180. Thirteen volumes of the study will be made available later (May?) for a price to be announced. George Cully Keesler AFB ------------------------------ From: jstone@shivasys.com (John Stone) Date: Thu, 28 Mar 1996 02:52:36 -0800 (PST) Subject: Bill Park...... Sorry if someone has already posted this but... I just read a blurb in the Lockheed Skunk Works Newspaper that Bill Park passed away March 17 at the 70. Second person to fly an A-12, the first and only person to pilot the D-21/M-21 combo. First to fly U-2R, and the first to land a U-2R on an aircraft carrier, and first to fly Have Blue. He went on to become Director of Flight Operations at Lockheed Skunk Works. :( Best, John | / ^ \ ___|___ -(.)==<.>==(.)- --------o---((.))---o-------- SR-71 Blackbird U-2 Dragon Lady John Stone jstone@shivasys.com U-2 and SR-71 Web Page http://www.shivasys.com/blackbird/ ------------------------------ From: albert.dobyns@mwbbs.com (ALBERT DOBYNS) Date: Thu, 28 Mar 96 18:58:00 -0500 Subject: re: Bill Park...... JS> Date: Thu, 28 Mar 1996 02:52:36 -0800 (PST) > To: skunk-works@mail.orst.edu > From: jstone@shivasys.com (John Stone) > Subject: Bill Park...... JS> Sorry if someone has already posted this but... JS> I just read a blurb in the Lockheed Skunk Works Newspaper that Bill Park > passed away March 17 at the 70. Second person to fly an A-12, the first and > only person to pilot the D-21/M-21 combo. First to fly U-2R, and the first > to land a U-2R on an aircraft carrier, and first to fly Have Blue. He went > on to become Director of Flight Operations at Lockheed Skunk Works. :( JS> Best, JS> John John, I'm glad you posted your note..otherwise I probably wouldn't have heard about it. He certainly had an interesting career! And I'm sure all would agree that he contributed a lot to expanding the limits of what can be done with some unique aircraft. I'm sure the aviation community will miss him. Al * SLMR 2.1a * This is not the time for a funny tagline. ------------------------------ From: Wei-Jen Su Date: Fri, 29 Mar 1996 03:50:52 -0500 (EST) Subject: "Spikes" and "fuzzball" Hello Skunkers!!! Here is a good topic that we can discuss and it is very skunky... Talking about Stealth, they come up with a new terminology: "spikes" and "fuzzball". What I understand a "spikes" is when they reflect the radiation to a different angle rather than return directly to the direction of emition (like a flat plate in a angle). And a "fuzzball" return the radiation to a low energy omnidirectional (like a ball). Anyone has better and more detail explanation? May the Force be with you Su Wei-Jen E-mail: wsu02@barney.poly.edu ------------------------------ End of Skunk Works Digest V5 #641 ********************************* 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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