From: owner-skunk-works-digest@netwrx1.com (skunk-works-digest) To: skunk-works-digest@netwrx1.com Subject: skunk-works-digest V8 #58 Reply-To: skunk-works@netwrx1.com Sender: owner-skunk-works-digest@netwrx1.com Errors-To: owner-skunk-works-digest@netwrx1.com Precedence: bulk skunk-works-digest Saturday, May 8 1999 Volume 08 : Number 058 Index of this digest by subject: *************************************************** Mach 1 Props Bombing the F-117 Re: Bombing the F-117 Non-Skunky question Re: Non-Skunky question RE: Non-Skunky question Re: SR-71 (968) Re: SR-71 (968) FWD: (TLC-Mission) F-111 [short history] RE: NEW X-34 SPACEPLANE TO BE UNVEILED AT DRYDEN OT: Need help wth a helicopter question Re: OT: Need help wth a helicopter question Re: OT: Need help wth a helicopter question Re: OT: Need help wth a helicopter question Borrowed from the AFNEWS Re: skunk-works-digest V8 #57 Free entry to win $1000.00 at PlanetRockCasino.com !! RE: skunk-works-digest V8 #57 NEWS: Better chance for crippled aircraft *************************************************** ---------------------------------------------------------------------- Date: Mon, 26 Apr 1999 08:50:36 -0700 From: David Lednicer Subject: Mach 1 Props A ducted or shrouded prop is a great way to go slow. Test data has shown time and time again that a shrouded prop has increased static thrust, but as the vehicle starts moving, the drag of the shroud starts increasing, eventually overtaking an gains from the ducted installation. In part, this is why turbofans on airliners have such a great dropoff in propulsive efficiency vs. turbojets as Mach increases. The only reason turbofans are prefered is that their higher bypass ratio gives them a higher overall propulsive efficiency. - ------------------------------------------------------------------- David Lednicer | "Applied Computational Fluid Dynamics" Analytical Methods, Inc. | email: dave@amiwest.com 2133 152nd Ave NE | tel: (425) 643-9090 Redmond, WA 98052 USA | fax: (425) 746-1299 ------------------------------ Date: Mon, 26 Apr 1999 08:57:42 -0700 From: David Lednicer Subject: Bombing the F-117 Bombing the F-117 wreckage would have been difficult and very risky for debatable benefit. Remember - it went down at night in a well defended area. By the time they could have found it to bomb it, the sun would have been up, increasing the risk. Not only that, but the pilot was still in the area until almost dawn and his rescue was higher priority. As to benefit - it would simply have taken big pieces or RAM and turned them into smaller pieces. The only way to deny anyone the wreckage would have been to vaporize it with a nuke. A compotent investigator can determine a lot from a tiny piece of wreckage. The AAIB figured out the Pan Am 747 bombing from a fragment of a computer chip from the bomb, found in a field. Second guessing is easy when you don't know all the facts! - ------------------------------------------------------------------- David Lednicer | "Applied Computational Fluid Dynamics" Analytical Methods, Inc. | email: dave@amiwest.com 2133 152nd Ave NE | tel: (425) 643-9090 Redmond, WA 98052 USA | fax: (425) 746-1299 ------------------------------ Date: Mon, 26 Apr 1999 21:51:26 -0700 From: jaz Subject: Re: Bombing the F-117 David Lednicer wrote: > Bombing the F-117 wreckage would have been difficult and very >risky for debatable benefit. Wouldn't Phosphorus or napalm work, let it burn for a bit, then bomb it. Charred and shattered. Would probably have little useful left. Wasn't the plane found in an open field? James Z. ------------------------------ Date: Tue, 27 Apr 1999 17:45:57 -0700 (PDT) From: Wei-Jen Su Subject: Non-Skunky question Hey guys, I have a non-skunky question for you. Probably people in here know a lot about it. I am looking for some commercial flight simulator software in which you can input the stability and control of the airplane and fly it. Anyone know any software that can simulate it? Preferable for low speed airplane. Yeah... I am testing the stability and control of the SR-71 that I built at low speed... Just kidding ;) May the Force be with you Wei-Jen Su E-mail: wsu@cco.caltech.edu - ------------------------------------------------------------------------------ "Picard's theorem. In the neighborhood of an isolated essential singularity "a", an otherwise analytic function "f(z)" can take on any value whatsoever with perhaps one exception." ------------------------------ Date: Thu, 29 Apr 1999 01:11:40 -0700 From: patrick Subject: Re: Non-Skunky question At 05:45 PM 4/27/99 -0700, Wei-Jen cautioned:> > > Yeah... I am testing the stability and control of the SR-71 that I >built at low speed... Just kidding ;) > >--------------------------------------------------------------------------- - --- You gotta master the takeoff's and landings before you can transition to high speed flight. You aren't fooling us for a minute Wei-Jen!! patrick ------------------------------ Date: Thu, 29 Apr 1999 10:48:27 -0700 From: Erik Hoel Subject: RE: Non-Skunky question Wei-Jen Su writes: > Hey guys, I have a non-skunky question for you. > Probably people in here know a lot about it. > I am looking for some commercial flight simulator software in > which you can input the stability and control of the airplane > and fly it. > Anyone know any software that can simulate it? Preferable for > low speed airplane. Try MS Combat Flight Simulator. They (MS) are now distributing a nice SDK for it as well. There is at least one SR-71 model out there (as well as a U-2R); goto: http://www.combatfs.com/warbirds/spy.shtml BTW - of course MS CFS is a WWII simulator, but people have built numerous models for newer aircraft. My observation has been that it is fairly difficult for a WWII era fighter to shoot down an SR-71 that is at speed and altitude. Snicker. Erik - -- Erik Hoel mailto:ehoel@esri.com Environmental Systems Research Institute http://www.esri.com 380 New York Street 909-793-2853 (x1-1548) tel Redlands, CA 92373-8100 909-307-3067 fax ------------------------------ Date: Thu, 29 Apr 1999 19:39:03 -0400 (EDT) From: Mary Shafer Subject: Re: SR-71 (968) This SR-71A had been brought over from the hangar at Plant 42 to be made flyable, as the idea of counting the Dryden B as their third airplane had only been a stopgap for the USAF. This plane will go back to Plant 42. The A we sent back, along with the other A, have been put into flyable storage, as has the B, and these two As are coming here. We're flying the LASRE plane without the half-model tenth-scale lifting body but with the canoe and reflection plane on two flights and then this plane's going into flyable storage. The reason we're keeping all this stuff installed is that there have been some inquiries about using the equipment. The idea is that we'll be able to fly half models on the one A and put other experiments on one of the unmodified (ex-USAF) As. We won't have to put the canoe and reflector plane on or take it off if we have an unmodified plane available. This is the straight skinny from Fast Eddie; I'm quoting his remarks to an international group of engineers and researchers who I took over for a quick look at the last Blackbird during lunch at the PIO Workshop they were attending. Mary Mary Shafer DoD #0362 KotFR shafer@ursa-major.spdcc.com "Some days it don't come easy/And some days it don't come hard Some days it don't come at all/And these are the days that never end...." On Thu, 19 Nov 1998 Xelex@aol.com wrote: > The "third" USAF Blackbird, SR-71A (61-7968), has been sitting out on the DET > 2 ramp for the last two days. It is missing its verticals and rear canopy. > It's kind of dusty, too. I'm not sure what they are planning to do with it. > > Also, thanks to everyone who gave me support in the face of my recent faux > pas. Everyone makes boo-boos from time to time. Some are just more boo-boo- > esque than others. > > Peter Merlin > ------------------------------ Date: Thu, 29 Apr 1999 20:08:10 -0400 (EDT) From: Mary Shafer Subject: Re: SR-71 (968) I forgot to mention that Fast Eddie made his remarks on 8 April. Mary Shafer DoD #0362 KotFR shafer@ursa-major.spdcc.com "Some days it don't come easy/And some days it don't come hard Some days it don't come at all/And these are the days that never end...." On Thu, 29 Apr 1999, Mary Shafer wrote: > This is the straight skinny from Fast Eddie; I'm quoting his remarks to an > international group of engineers and researchers who I took over for a > quick look at the last Blackbird during lunch at the PIO Workshop they > were attending. ------------------------------ Date: Sat, 01 May 1999 23:35:59 -0700 From: "Terry W. Colvin" Subject: FWD: (TLC-Mission) F-111 [short history] Recently we had a bit of traffic on the TLC Mission server re the problem encountered by the F-111 on its initial combat test in SEA. I just received my monthly bulletin from the 30th Flight, The Order of Daedalians which meets at March ARB. The bulletin gives a short, interesting summary of last month's presentation on the F-111 by LTC "Fuzzy" Zeller, a former "Aardvark" pilot. An excerpt from the bulletin follows: ***************************************************************************** LTC Fuzzy Zeller flew down from Edwards to give us the history of the F-1ll (and FB- and EF-). He brought Lockheed Martin test pilot Terry Tomeny along to see us. Mr. McNamara's mandated "Common Fighter" for the armed forces started out at 42,000 pounds empty, and got rapidly worse. The Navy wanted none of it--their short-nose F-lllB rutted the deck! The tail slab is the size of a Mig-21 wing! The big bird got a bad rap in "Coronet Lancer", its initial test in Vietnam (Laos). What initially was blamed on the terrain following system eventually proved to be a bad weld in the stabilator which caused pitch-down. The F-111 was the best deep-strike fighter in the world. The plane served well in combat, including its second tour in Vietnamm, the Libyan raid,and Desert Shield/Storm. A total of 563 were built. Only the Aussies still have them in operational service, the F-l1lC. They plan to retire them around 2020. (Bob's comment: I was in the 20th TFW at RAF Upper Heyford during 1975 - 1978. The 20th was equipped with the F-111E which was the only truly viable all-weather, nuclear strike aircraft in the NATO inventory throughtout most of the '70s. The 48th TFW converted from F-4s to F-111Fs around 1979 and those two wings remained the only NATO strike units with terrain following systems into the mid '80s. The only way that strike aircraft could avoid the extensive Warsaw Pact air defense system at that time was by hugging the terrain to stay below radar. With the lone exception of the F-111, NATO aircraft required weather that would allow pilots to see and avoid ground obstacles. In bad weather--typical in Europe-- only the F-111 could hug the ground using its terrain following avionics. Furthermore, it carried two "nukes", the other aircraft only one. It was one helluva fine aircraft with excellent capabilities. The "Aardvark" was greatly admired by the aircrews who flew her in USAFE.) The F-111 is mach 2+. Zeller has had it to 2.4. The escape pod weighs 4,000 pounds, and must go through 122 separate sequential functions to work. If it does, and the 'chute deploys, there is a final squib that is supposed to let you hit keel down. Otherwise, you go in on your nose, and it does hit hard. The F-111 has a fuel jettison system that vents at the tail. Some pilots found that a spectacular show could be put on by dumping a bit of fuel then lighting the afterburner. The torch could be seen for miles! Zeller has more than a thousand hours in the F-1ll. **************************************************************************** Bob Arnau 21st SOS, "Knife" (CH-3E) NKP 1969-70 Riverside, CA - -- Terry W. Colvin, Sierra Vista, Arizona (USA) < fortean@primenet.com > Home Page: < http://www.geocities.com/Area51/Shadowlands/8832 > Sites: Fortean Times * Northwest Mysteries * Mystic's Cyberpage * TLCB * U.S. Message Text Formatting (USMTF) Program - ------------ Member: Thailand-Laos-Cambodia Brotherhood (TLCB) Mailing List TLCB Web Site: < http://www.tlc-brotherhood.org > Southeast Asia (SEA) service: Vietnam - Theater Telecommunications Center/HHC, 1st Aviation Brigade (Jan 71 - Aug 72) Thailand/Laos - Telecommunications Center/U.S. Army Support Thailand (USARSUPTHAI), Camp Samae San (Jan 73 - Aug 73) - Special Security/Strategic Communications - Thailand (STRATCOM - Thailand), Phu Mu (Pig Mountain) Signal Site (Aug 73 - Jan 74) ------------------------------ Date: Mon, 3 May 1999 09:58:23 +0930 From: Craig Norton Subject: RE: NEW X-34 SPACEPLANE TO BE UNVEILED AT DRYDEN Can someone confirm that the rollout actually happened, and if so are their any photo's that NASA has released ?? Craig... >-----Original Message----- >From: Martin Hurst [SMTP:martinh@ix.netcom.com] >Sent: Friday, April 23, 1999 11:49 AM >To: 'Skunk Works - post to the list' >Subject: NEW X-34 SPACEPLANE TO BE UNVEILED AT DRYDEN > >NASA press releases: > > The first of three X-34 demonstration vehicles will be >"rolled out" at NASA's Dryden Flight Research Center, >Edwards, CA, on Friday, April 30, opening an era of low-cost >reusable space planes. > > The X-34, a single-engine rocket plane, will fly itself >using onboard computers. The vehicle is approximately 58 >feet long, 28 feet wide at wing tip and 11 feet tall from >the bottom of the fuselage to the top of the tail. The X-34 >will launch from an L-1011 airliner and will reach altitudes >of up to 250,000 feet and travel up to eight times faster >than the speed of sound. > > Flights of the X-34 will test many new technologies: >composite material structures, composite tanks and new, >integrated avionics. The vehicle also will demonstrate the >ability to fly through inclement weather, land horizontally >at a designated landing site, and safely abort during >flight. The planned 27 flights within a year will >demonstrate the program's ability to fly within 24 hours of >its last mission, using a small ground crew. > > The X-34 has completed ground vibration tests, ensuring >there will be no potentially hazardous vibrations during >flight. The L-1011 and the X-34 prototype were tested >separately and together at Dryden. > > After the rollout, the X-34 will be mounted underneath >the L-1011 and flown on "captive-carry" flights to allow the >Federal Aviation Administration to approve modifications to >the L-1011. When powered flights begin for X-34, the >demonstrator will be carried aloft and separate from the L- >1011 before igniting its rocket engine. Following the >powered portion of flight, the unpiloted X-34 will land >horizontally, initially on a dry lakebed and eventually on a >runway. > > The April 30 rollout, which is open to the media, will >air live on NASA Television. A press conference will be held >at 1 p.m. EDT, and the rollout ceremony will take place at 2 >p.m. EDT. For accreditation and more information, reporters >should contact Leslie Mathews at Dryden Public Affairs on >(661) 258-3893. > > NASA TV is available on GE-2, transponder 9C at 85 >degrees west longitude, with vertical polarization. >Frequency is on 3880.0 megahertz, with audio on 6.8 >megahertz. > > In a cooperative program among NASA Centers, Dryden >will provide flight-testing and ground vibration testing. >NASA's Marshall Space Flight Center, Huntsville, AL, manages >the X-34 project. Orbital Sciences Corporation Dulles, VA, >is designing, developing and testing the vehicle. > > - end - >NASA press releases and other information are available automatically >by sending an Internet electronic mail message to domo@hq.nasa.gov. >In the body of the message (not the subject line) users should type >the words "subscribe press-release" (no quotes). The system will >reply with a confirmation via E-mail of each subscription. A second >automatic message will include additional information on the service. >NASA releases also are available via CompuServe using the command >GO NASA. To unsubscribe from this mailing list, address an E-mail >message to domo@hq.nasa.gov, leave the subject blank, and type only >"unsubscribe press-release" (no quotes) in the body of the message. > ------------------------------ Date: Mon, 03 May 1999 00:42:47 GMT From: georgek@netwrx1.com (George R. Kasica) Subject: OT: Need help wth a helicopter question Hello: I know this is WAY OT, but...I need some info on the helicopters used by the Mileaukee Regional Medical Center Flight For Life program. A 1998 news story mentions a KU117 but repeated web searches turn up zip....its for a patient there who is quite ill and also a big aircraft buff....my wife happens to be his primary nurse, hence the weird round about way of the request....I always thought they used Bell JetRanger or LongRangers but..... Thanks for any assistance you can provide. George George, MR. Tibbs & The Beast Kasica West Allis, WI USA georgek@netwrx1.com gkasica@hotmail.com gkasica@lycos.com gkasica@netscape.com http://www.netwrx1.com ICQ #12862186 Zz zZ |\ z _,,,---,,_ /,`.-'`' _ ;-;;,_ |,4- ) )-,_..;\ ( `'_' '---''(_/--' `-'\_) ------------------------------ Date: Sun, 02 May 1999 22:59:23 -0500 From: Dave Bethke Subject: Re: OT: Need help wth a helicopter question "George R. Kasica" wrote: > I know this is WAY OT, but...I need some info on the helicopters used > by the Mileaukee Regional Medical Center Flight For Life program. A > 1998 news story mentions a KU117 but repeated web searches turn up > zip.... Could that be a BK 117, made by MESSERSCHMITT-BOLKOW-BLOHM of Germany? The Milwaukee County Regional Medical Center web page says that's the model they use. (http://www.mcw.edu/emr/medical_services.html) It appears to be used by quite a few medical facilities, including Hermann Life Flight here in Houston. (And that's where I started my Web search. :-)) - -- Dave Bethke - (ex-Milwaukeean) on the fringe of Houston ------------------------------ Date: Mon, 03 May 1999 10:39:58 GMT From: georgek@netwrx1.com (George R. Kasica) Subject: Re: OT: Need help wth a helicopter question John: Thank you! I sort of took the bull by the horns here and called the Flight For Life dispatch center and got connected to the on-duty pilot, Jim, he was happy to talk to me and I found out they are flying a BK-117 from Messcherschmidt/Kawasaki and a Bell 222UT to be replaced soon the another BK-117. Finding info for the BK-117 was easy, the Bell 222UT was not, took several hours of web searching bit I did find enough to make the pt. happy. Thanks again, George ===[George R. Kasica]=== +1 414 541 8579 Skunk-Works ListOwner +1 800 520 4873 FAX http://www.netwrx1.com West Allis, WI USA georgek@netwrx1.com gkasica@hotmail.com gkasica@lycos.com gkasica@netscape.com ICQ #12862186 Digest Issues at: http://www.netwrx1.com/skunk-works ------------------------------ Date: Mon, 03 May 1999 10:48:15 GMT From: georgek@netwrx1.com (George R. Kasica) Subject: Re: OT: Need help wth a helicopter question On Sun, 02 May 1999 22:59:23 -0500, you wrotd: >"George R. Kasica" wrote: > >> I know this is WAY OT, but...I need some info on the helicopters used >> by the Mileaukee Regional Medical Center Flight For Life program. A >> 1998 news story mentions a KU117 but repeated web searches turn up >> zip.... > > Could that be a BK 117, made by MESSERSCHMITT-BOLKOW-BLOHM of >Germany? The Milwaukee County Regional Medical Center web page says >that's the model they use. >(http://www.mcw.edu/emr/medical_services.html) It appears to be used by >quite a few medical facilities, including Hermann Life Flight here in >Houston. (And that's where I started my Web search. :-)) Dave: You're exactly correct...I read the Waukesha Freeman article and they have a misprint I think KU117, I SAW the above web site and totally blew it and missed seeing that info...I re-looked now and feel somewhat stupid...oh well,it was late here.....yeah thats my story and I'm sticking to it... Thanks again, George George, MR. Tibbs & The Beast Kasica West Allis, WI USA georgek@netwrx1.com gkasica@hotmail.com gkasica@lycos.com gkasica@netscape.com http://www.netwrx1.com ICQ #12862186 Zz zZ |\ z _,,,---,,_ /,`.-'`' _ ;-;;,_ |,4- ) )-,_..;\ ( `'_' '---''(_/--' `-'\_) ------------------------------ Date: Sat, 8 May 1999 01:17:46 +0000 From: John Szalay Subject: Borrowed from the AFNEWS Since the list seems to be slow, heres a press release from the AFNEWS - ----------------------------------------------------------------------------- 990888. 'Stealth works,' says wing commander > by Senior Master Sgt. Jim Katzaman > Air Force Print News > > WASHINGTON -- After "a bunch" of sorties which dropped more than 1 million > pounds of ordnance on Yugoslav targets, the B-2 Spirit wing commander had > a triumphant message: "Stealth works." > > From the first days of NATO's Operation Allied Force, B-2s have taken off > from Whiteman Air Force Base, near Knob Noster, Mo.; flown almost 15 hours > to Yugoslavia; dropped precision-guided munitions on fixed ground sites; > and returned after another 15 hours to Missouri. Often, in the time it takes > to take on a new load of bombs, aircraft and crews are on their way again. > > "The jet's performance really has exceeded all of our expectations," said > Brig. Gen. Leroy Barnidge Jr., 509th Bomb Wing commander, who spoke May 5 > to the Pentagon press corps. > > He called the B-2, "a combination of stealth, long range, large payload > and precise munitions. It's not only a world-class, long-range bomber, but > also a pretty valuable asset to have in the skies over Serbia today." > > Asked if the B-2 program was worth its $40 billion estimated cost, the > general said, "it's worth three times that amount. This jet works, and it > keeps our guys alive. It keeps Americans alive." > > He then described a typical sortie with two pilots on each bomber carrying > up to 16 2,000-pound bombs converted into joint direct-attack munitions. > With JDAM modifications, unguided free-fall bombs become precision-guided > "smart" munitions. Already, B-2s have dropped more than 500 JDAMs on > Yugoslav targets, according to Barnidge. > > "The B-2s go out there and carry 16 very precise munitions," he said. > Although the smaller F-117A stealth bomber is "a wonderful machine," he > said, "it can only carry two 2000-pound laser-guided bombs. > > "A B-2 is equivalent to eight F-117s. We can take this thing thousands of > miles; we can go into very lethal environments, and we can put the bombs > exactly where we want them. Then we bring the guys home, turn the jets > and do it again. That's not a bad return on your investment." > > "The marvel of this operation has been that we seamlessly integrate with > an entire NATO strike package even though we launch 13 to 14 hours before > everybody else does," Barnidge said. "We seamlessly integrate with them > because of the planning process. I could not ask for a better, more > integrated planning process and user-friendly operation." > > The B-2 and JDAM combination, the general added, has also reaped dividends > where battlefield commanders demand it most: on the ground. > > "I've seen zero collateral damage from our strikes," Barnidge said, "and > that's a pretty good record." > > Neither bomber nor bombs would work as well as they do today, the wing > commander said, without "the folks who work in and around the B-2. They > are the heroes of B-2 operations. They're clearly the best team I've ever > had." > > Although the bat-winged B-2 might be the star of the show, the general > noted, "We are a small part of a pretty big team out there comprised not > only of our American air power team, but also the NATO alliance. > > "Our view from Whiteman and central Missouri is that we're just real glad > that we can make a valuable contribution to this team, and we plan to > continue to do just that," he said. > ----------------------------------------------------------------------------- ------------------------------ Date: Fri, 07 May 1999 23:31:15 -0400 From: Don Hackett Subject: Re: skunk-works-digest V8 #57 Where are you? Haven't received anything in 11 days. ------------------------------ Date: Sat, 8 May 1999 00:04:45 From: planetrockcasino@hotmail.com Subject: Free entry to win $1000.00 at PlanetRockCasino.com !! Here is your entry to win our $1000.00 giveaway, cds and concert tickets. 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Haven't received anything in 11 days. ------------------------------ Date: Sat, 08 May 1999 20:26:51 +0200 From: Frits Westra Subject: NEWS: Better chance for crippled aircraft URL: http://www.newscientist.com/ns/19990424/newsstory2.html News Crash course Duncan Graham-Rowe CRIPPLED COMBAT AIRCRAFT should soon stand a better chance of making it back to base, thanks to a novel neural network that has just passed its first major test. When the control surfaces of an aeroplane, such as the rudder or ailerons, are damaged or malfunctioning there is often very little a pilot can do to avert a disaster. But in a series of tests that finished last week, NASA engineers have shown that smart software can keep aircraft flying even if some of their control surfaces are disabled. The tests, at NASA's Dryden Flight Research Center in Edwards, California, used a modified F-15 aircraft similar to those flying combat missions against Serbia. The software was tested in high performance manoeuvres, such as tracking a target or performing a 360 degree roll. The neural net managed to keep disabled planes under control even at supersonic speeds. This is the first time such a system has helped control a piloted aircraft. The software was developed at NASA's Ames Research Center in Moffett Field, California. It is designed to kick in when the flight control system detects a mismatch between data on the plane's airspeed, bearing and the forces on its wings, tail and fuselage, and a computer model showing what data should be received if the plane were flying normally. Neural networks are programs that learn to perform a certain task by trial and error, rather like the human brain. The Ames team trained theirs to control an F-15 on a flight simulator, before letting it loose on the real thing. In an emergency, the network reassesses flight data six times every second to work out the best way of using the available control surfaces and the plane's engines to maintain normal flight. The pilot would be warned of any failures, such as the loss of his ailerons. But in most cases, he shouldn't notice that the plane is handling differently from normal. "The computer would determine that the ailerons aren't available and would have another scheme in mind," says Mike Thomson, the engineer at Dryden who supervised the tests. "It would learn to use another control surface instead." Thomson believes commercial airliners could also benefit from the system, although it would be restricted to modern fly-by-wire planes. When an airliner loses its control surfaces, the results can be horrific: at Sioux City, Iowa, in 1989, a full hydraulic failure left an aircrew trying to land a DC-10 using only the throttles of its two remaining engines. It crash-landed, killing 110 passengers. However, civil authorities may be less willing than the military to embrace the system. They will demand standardised tests of the system's performance, says Tom Anderson, an expert on software reliability at Newcastle University. But such tests will be hard to devise, as the performance of neural networks is inherently difficult to predict. From New Scientist, 24 April 1999 ------------------------------ End of skunk-works-digest V8 #58 ******************************** To subscribe to skunk-works-digest, send the command: subscribe in the body of a message to "majordomo@netwrx1.com". 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 local-skunk-works@your.domain.net To unsubscribe, send mail to the same address, with the command: unsubscribe in the body. Administrative requests, problems, and other non-list mail can be sent to georgek@netwrx1.com. 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 viewing by a www interface located at: http://www.netwrx1.com/skunk-works If you have any questions or problems please contact me at: georgek@netwrx1.com Thanks, George R. Kasica Listowner