From: owner-skunk-works-digest@netwrx1.com (skunk-works-digest) To: skunk-works-digest@netwrx1.com Subject: skunk-works-digest V9 #27 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 Wednesday, April 12 2000 Volume 09 : Number 027 Index of this digest by subject: *************************************************** Re: YF-113G RE: B-2 Changing Colour? Re: YF-113G RE: B-2 Changing Colour? Re: B-2 Changing Colour? Re: YF-113G RE: B-2 Changing Colour? Re: B-2 Changing Colour? Re: B-2 Changing Colour? Re: B-2 Changing Colour? Re: B-2 groans (Was: B-2 Changing Colour?) Re: B-2 Changing Colour? RE: B-2 Changing Colour? RE: B-2 groans (Was: B-2 Changing Colour?) Re: B-2 Changing Colour? Re: B-2 Changing Colour? *************************************************** ---------------------------------------------------------------------- Date: Wed, 12 Apr 2000 00:18:29 EDT From: Xelex@aol.com Subject: Re: YF-113G Many of the "extended century series" aircraft were of foreign manufacture. Some (YF-113G, YF-117A, YF-117D, etc.) were made in the USA, as prototypes and demonstrators. Peter Merlin ------------------------------ Date: Wed, 12 Apr 2000 13:58:14 +0930 From: Dennis Lapcewich Subject: RE: B-2 Changing Colour? Considering the French prefer to go their own way in all things, including military alliances, why would they be shown such characteristics of a B-2. I find it hard to believe the French could ever be "duly impressed" by anything not French. :) Seems someone spread a little grey poupon on your sandwich ... :) > Intelligence, N. 61, 2 June 1997, p. 11 > > STEALTH - A Colorful "Private" Show in Paris. > > According to French intelligence rumors, a select group of French > military figures were very impressed last week by a "private" > demonstration inside a secured hangar at Le Bourget near Paris. In > preparation for the coming Paris Air Show at Le Bourget, a > U.S. B-2 stealth bomber arrived and was immediately "put under wraps". > The select group visited the hangar and watched in amazement as a B-2 > crew member in the cockpit changed the color of the aircraft from sky > gray to camouflage green and then to jet black. The technology for > variable aircraft coloration has been under development for some time > and was known now to be available. Apparently, by changing the > aircraft's skin temperature with embedded heating elements, the > thermally active paint changes color. French authorities were duly > impressed. > ..................................... > > > ------------------------------ Date: Wed, 12 Apr 2000 01:10:03 -0400 (EDT) From: Sam Kaltsidis Subject: Re: YF-113G > >My thoughts tie in with "acquired" Soviet hardware too. > > > >There were so many defections and covert thefts during the Cold War that I > >think its about time now that people start to ask what happened to them. > >The same sort of thing is happening with submarines. > > > > > >Prehaps we can compile a list of what we know the Americans have somewhere? > >I know off the top of my head they've got Mig-21s, 23s, 25s, 27s, and 29s. > >I once heard a rumour of a Bear lurking somewhere in the Nevada desert. > > > Yup, and they're asking for $75m this year (FY01) in the DoD budget, > down from $85m last year. The Air Force museam has several > Russian-desinged aircraft that came out of the Red Hats program and > furnishes short histories for each, the Smithsonian also has at least > one MiG-21 from the Red Hats. > > From the FY01 DoD RDT& E PROGRAMS (R- 1) > No Number Item Act FY 1999 FY 2000 FY 2001 > [124 0207248F Special Evaluation Program 7 97,142 84,162 75,443] > (Numbers are in thousands of dollars) > > This item has long been thought to be funding for the Red Hats- Paul > McGinnis' very well researched FY95 classified program analysis > states: > > 148 0207248F "special evaluation program" / $118.3 million / (until > fiscal year 1994, this program was known as "special > tactical unit detachments" and was funded like other > tactical aircraft units, such as F-117A squadrons. One > wonders what kind of aircraft are being flown in this > program...) > > With more and more former Warsaw Pact nations working with the US and > it's allies, and even training at Nellis, the need for the services > that the Red Hats performed in the past has diminished considerably. > > > Dan > > > _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ > The software you were born with helps > you write code into the wee small hours, > find the bugs in your competitors' products, > and create fake demos for the first > six months of a project. It deserves > the operating system designed to work > with it: the MacOS. > _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ > The best way to defeat your enemy is to know your enemy. If we have the opportunity to experiment with non-western aircraft and other aircraft not in US inventory we should take full advantage of it. It never hurts to be prepared, just in case. Weapons from all sources are proliferating rapidly and remaining prepared is increasingly important as it is impossible to determine when and where some rogue nation or even a nation we consider an ally decides to do something retarded. Sam ------------------------------ Date: Wed, 12 Apr 2000 01:14:33 -0400 (EDT) From: Sam Kaltsidis Subject: RE: B-2 Changing Colour? > Considering the French prefer to go their own way in all things, including > military alliances, why would they be shown such characteristics of a B-2. I > find it hard to believe the French could ever be "duly impressed" by anything > not French. :) > > Seems someone spread a little grey poupon on your sandwich ... :) > Aye, I agree... I do not mean to offend anyone but I wouldn't trust the French with such information in a million years. I am confident they wouldn't trust us with their secrets either and I wouldn't blame them. Sam > > > Intelligence, N. 61, 2 June 1997, p. 11 > > > > STEALTH - A Colorful "Private" Show in Paris. > > > > According to French intelligence rumors, a select group of French > > military figures were very impressed last week by a "private" > > demonstration inside a secured hangar at Le Bourget near Paris. In > > preparation for the coming Paris Air Show at Le Bourget, a > > U.S. B-2 stealth bomber arrived and was immediately "put under wraps". > > The select group visited the hangar and watched in amazement as a B-2 > > crew member in the cockpit changed the color of the aircraft from sky > > gray to camouflage green and then to jet black. The technology for > > variable aircraft coloration has been under development for some time > > and was known now to be available. Apparently, by changing the > > aircraft's skin temperature with embedded heating elements, the > > thermally active paint changes color. French authorities were duly > > impressed. > > ..................................... > > > > > > > ------------------------------ Date: Wed, 12 Apr 2000 11:46:41 +0100 From: "Gavin Payne" Subject: Re: B-2 Changing Colour? I agree with you all totally. I don't know what this Intelligence magazine is, I just saw the posting on Usenet. Considering the French are said to have tipped Saddam off about a truck load of ALCMs in B-52s sitting on his doorstep a while ago I doubt the US would let them see this "special" technology. I can't imagine the French being able to afford this type of technology either. The only reason they can afford to have a military the size they do is because most of it they make themselves so no money leaves the country. - ----- Original Message ----- From: "Sam Kaltsidis" To: Sent: Wednesday, April 12, 2000 6:14 AM Subject: RE: B-2 Changing Colour? > > Considering the French prefer to go their own way in all things, including > > military alliances, why would they be shown such characteristics of a B-2. I > > find it hard to believe the French could ever be "duly impressed" by anything > > not French. :) > > > > Seems someone spread a little grey poupon on your sandwich ... :) > > > > > Aye, I agree... > > I do not mean to offend anyone but I wouldn't trust the French with such > information in a million years. I am confident they wouldn't trust us with their > secrets either and I wouldn't blame them. > > > Sam > > > > > > > Intelligence, N. 61, 2 June 1997, p. 11 > > > > > > STEALTH - A Colorful "Private" Show in Paris. > > > > > > According to French intelligence rumors, a select group of French > > > military figures were very impressed last week by a "private" > > > demonstration inside a secured hangar at Le Bourget near Paris. In > > > preparation for the coming Paris Air Show at Le Bourget, a > > > U.S. B-2 stealth bomber arrived and was immediately "put under wraps". > > > The select group visited the hangar and watched in amazement as a B-2 > > > crew member in the cockpit changed the color of the aircraft from sky > > > gray to camouflage green and then to jet black. The technology for > > > variable aircraft coloration has been under development for some time > > > and was known now to be available. Apparently, by changing the > > > aircraft's skin temperature with embedded heating elements, the > > > thermally active paint changes color. French authorities were duly > > > impressed. > > > ..................................... > > > > > > > > > > > > ------------------------------ Date: Wed, 12 Apr 2000 11:49:37 +0100 From: "Gavin Payne" Subject: Re: YF-113G Without getting too deep, how many aircraft do you think they could look after for that amount of money? With the amount of secrey involved I can't imagine it being that many. - ----- Original Message ----- From: "Sam Kaltsidis" To: Sent: Wednesday, April 12, 2000 6:10 AM Subject: Re: YF-113G > > >My thoughts tie in with "acquired" Soviet hardware too. > > > > > >There were so many defections and covert thefts during the Cold War that I > > >think its about time now that people start to ask what happened to them. > > >The same sort of thing is happening with submarines. > > > > > > > > >Prehaps we can compile a list of what we know the Americans have somewhere? > > >I know off the top of my head they've got Mig-21s, 23s, 25s, 27s, and 29s. > > >I once heard a rumour of a Bear lurking somewhere in the Nevada desert. > > > > > > Yup, and they're asking for $75m this year (FY01) in the DoD budget, > > down from $85m last year. The Air Force museam has several > > Russian-desinged aircraft that came out of the Red Hats program and > > furnishes short histories for each, the Smithsonian also has at least > > one MiG-21 from the Red Hats. > > > > From the FY01 DoD RDT& E PROGRAMS (R- 1) > > No Number Item Act FY 1999 FY 2000 FY 2001 > > [124 0207248F Special Evaluation Program 7 97,142 84,162 75,443] > > (Numbers are in thousands of dollars) > > > > This item has long been thought to be funding for the Red Hats- Paul > > McGinnis' very well researched FY95 classified program analysis > > states: > > > > 148 0207248F "special evaluation program" / $118.3 million / (until > > fiscal year 1994, this program was known as "special > > tactical unit detachments" and was funded like other > > tactical aircraft units, such as F-117A squadrons. One > > wonders what kind of aircraft are being flown in this > > program...) > > > > With more and more former Warsaw Pact nations working with the US and > > it's allies, and even training at Nellis, the need for the services > > that the Red Hats performed in the past has diminished considerably. > > > > > > Dan > > > > > > _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ > > The software you were born with helps > > you write code into the wee small hours, > > find the bugs in your competitors' products, > > and create fake demos for the first > > six months of a project. It deserves > > the operating system designed to work > > with it: the MacOS. > > _/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/_/ > > > > > The best way to defeat your enemy is to know your enemy. If we have the > opportunity to experiment with non-western aircraft and other aircraft not in US > inventory we should take full advantage of it. It never hurts to be prepared, > just in case. Weapons from all sources are proliferating rapidly and remaining > prepared is increasingly important as it is impossible to determine when and > where some rogue nation or even a nation we consider an ally decides to do > something retarded. > > Sam > ------------------------------ Date: Wed, 12 Apr 2000 09:19:10 -0400 From: "Weigold, Greg" Subject: RE: B-2 Changing Colour? This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. - ------_=_NextPart_001_01BFA481.B06E5842 Content-Type: text/plain; charset="iso-8859-1" Here's a thought..... The whole story is a fake, to put out counter-intelligence that we have such a system working on the B-2, which would go a long way toward combining radar stealth with optical stealth.... this would hopefully make other countries (Russia?) try to develop such a system OR try to develop a system that would optically track planes that can mimic the background color of the sky behind them.... I agree that the French would be one of the last large 'allied' countries that we would show such a system too, or offer to share the technology with... their track record for the last 300 years hasn't been too good...... Greg W - -----Original Message----- - ------_=_NextPart_001_01BFA481.B06E5842 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable RE: B-2 Changing Colour?

Here's a thought.....

The whole story is a fake, to put out = counter-intelligence that we have such a system working on the B-2, = which would go a long way toward combining radar stealth with optical = stealth....  this would hopefully make other countries (Russia?) = try to develop such a system OR try to develop a system that would = optically track planes that can mimic the background color of the sky = behind them....

I agree that the French would be one of the last = large 'allied' countries that we would show such a system too, or offer = to share the technology with...  their track record for the last = 300 years hasn't been too good......

Greg W

-----Original Message-----

- ------_=_NextPart_001_01BFA481.B06E5842-- ------------------------------ Date: Wed, 12 Apr 2000 09:03:10 PDT From: "wayne binkley" Subject: Re: B-2 Changing Colour? i'm a little skeptical about this B-2 thermally active paint story.isn't the B-2s skin made of carbon fiber? what effect on it's RCS would result from putting a cover of wires in some kind of paint?wouldn't all the wires have to be controlled by computer?the skin temp is constantly changing.the temp near the engines and exhaust is different than the leading edges.the fuel tanks have a lot of thermal mass and react differently than fillet fairings.wouldn't sensors be required to compensate?how would they be installed with out messing up the acft skin? wayne d.binkley >From: "Gavin Payne" >Reply-To: skunk-works@netwrx1.com >To: >Subject: Re: B-2 Changing Colour? >Date: Wed, 12 Apr 2000 11:46:41 +0100 > >I agree with you all totally. > >I don't know what this Intelligence magazine is, I just saw the posting on >Usenet. >Considering the French are said to have tipped Saddam off about a truck >load >of ALCMs in B-52s sitting on his doorstep a while ago I doubt the US would >let them see this "special" technology. > >I can't imagine the French being able to afford this type of technology >either. The only reason they can afford to have a military the size they >do >is because most of it they make themselves so no money leaves the country. > > >----- Original Message ----- >From: "Sam Kaltsidis" >To: >Sent: Wednesday, April 12, 2000 6:14 AM >Subject: RE: B-2 Changing Colour? > > > > > Considering the French prefer to go their own way in all things, >including > > > military alliances, why would they be shown such characteristics of a >B-2. I > > > find it hard to believe the French could ever be "duly impressed" by >anything > > > not French. :) > > > > > > Seems someone spread a little grey poupon on your sandwich ... :) > > > > > > > > > Aye, I agree... > > > > I do not mean to offend anyone but I wouldn't trust the French with such > > information in a million years. I am confident they wouldn't trust us >with >their > > secrets either and I wouldn't blame them. > > > > > > Sam > > > > > > > > > > > Intelligence, N. 61, 2 June 1997, p. 11 > > > > > > > > STEALTH - A Colorful "Private" Show in Paris. > > > > > > > > According to French intelligence rumors, a select group of French > > > > military figures were very impressed last week by a "private" > > > > demonstration inside a secured hangar at Le Bourget near Paris. In > > > > preparation for the coming Paris Air Show at Le Bourget, a > > > > U.S. B-2 stealth bomber arrived and was immediately "put under >wraps". > > > > The select group visited the hangar and watched in amazement as a >B-2 > > > > crew member in the cockpit changed the color of the aircraft from >sky > > > > gray to camouflage green and then to jet black. The technology for > > > > variable aircraft coloration has been under development for some >time > > > > and was known now to be available. Apparently, by changing the > > > > aircraft's skin temperature with embedded heating elements, the > > > > thermally active paint changes color. French authorities were duly > > > > impressed. > > > > ..................................... > > > > > > > > > > > > > > > > > > ______________________________________________________ Get Your Private, Free Email at http://www.hotmail.com ------------------------------ Date: Wed, 12 Apr 2000 18:27:57 +0100 From: "David" Subject: Re: B-2 Changing Colour? FWIW, I don't buy this story on a number of counts. I don't see Le Bourget as the kind of place such a highly classified demo would take place. Can't see the point of the demo - no country ( including the France) is going to buy any Spirits, so why show anything about the a/c that doesn't need to be shown ? As you say, the a/c won't be a standard temp all over, so if the colour change is thermally controlled, it's going to look like something from an Austin Powers movie or Jimi Hendrix album cover. I heard the colour shift effect on whatever test a/c it's used on, was generated by a similar tech. as flat panel monitors, and was primarily aimed at confusing line scanning video cameras on missiles rather than a creating a Klingon cloaking device. It's my understanding that matching the luminance of the object to the sky or ground is the real key to reducing its visible sig ( i.e. Project Yehudi). D From: wayne binkley | i'm a little skeptical about this B-2 thermally active paint story.isn't the | B-2s skin made of carbon fiber? what effect on it's RCS would result from | putting a cover of wires in some kind of paint?wouldn't all the wires have | to be controlled by computer?the skin temp is constantly changing.the temp | near the engines and exhaust is different than the leading edges.the fuel | tanks have a lot of thermal mass and react differently than fillet | fairings.wouldn't sensors be required to compensate?how would they be | installed with out messing up the acft skin? ------------------------------ Date: Wed, 12 Apr 2000 19:01:59 +0100 From: "Gavin Payne" Subject: Re: B-2 Changing Colour? > i'm a little skeptical about this B-2 thermally active paint story.isn't the > B-2s skin made of carbon fiber? The centre is made from carbon fibres the wings are made from composite materials/plastics. Or so they tell us (sorry I just had to say that!) Whenever its taxying(?) you can hear it a mile off and keep waiting for it to snap! ------------------------------ Date: Wed, 12 Apr 2000 14:11:16 -0500 From: "Allen Thomson" Subject: Re: B-2 groans (Was: B-2 Changing Colour?) > > B-2s skin made of carbon fiber? > > The centre is made from carbon fibres the wings are made from composite > materials/plastics. Or so they tell us (sorry I just had to say that!) > Whenever its taxying(?) you can hear it a mile off and keep waiting for it > to snap! Really? As in the B-2 creaks, groans, pops etc. loudly while the plane is rolling along? (I've never been near one of the things and wouldn't know.) BTW and just as an aside, this thread on a variable-color/colour paint job reminded me of the minor flap several years ago in which the B-2's skin was said to be very sensitive to water damage. I never quite understood that, as the plane's radar stealth obviously depends mostly on shaping. But -- and this is very, very speculative -- if there were some optical stealthiness such as a variable-color surface treatment used, that might explain the hydrophobia. A random notion in search of evidence. ------------------------------ Date: Wed, 12 Apr 2000 14:25:13 -0500 From: "Tom C Robison" Subject: Re: B-2 Changing Colour? Gavin wrote: "The centre is made from carbon fibres the wings are made from composite materials/plastics. Or so they tell us (sorry I just had to say that!) Whenever its taxying(?) you can hear it a mile off and keep waiting for it to snap!" Wonder how many tubes of Testors airplane glue it takes to build a B-2? ------------------------------ Date: Wed, 12 Apr 2000 12:39:39 -0700 From: Erik Hoel Subject: RE: B-2 Changing Colour? Tom wrote in response to Gavin: >> "The centre is made from carbon fibres the wings are made >> from composite >> materials/plastics. Or so they tell us (sorry I just had to >> say that!) >> Whenever its taxying(?) you can hear it a mile off and keep >> waiting for it to snap!" > > Wonder how many tubes of Testors airplane glue it takes to > build a B-2? Why is it necessary to build the center (I am assuming that Gavin means the wing spars) of carbon fibers rather than an aluminum alloy of some sort? Would this be for weight reduction, or is it for stealth (or both)? If it is for stealth, are there other bits that one would normally find in the wings that are also made from composites/carbon fiber (e.g., tubing, hinges, etc.) for this same reason? 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: Wed, 12 Apr 2000 16:10:34 -0400 From: "Weigold, Greg" Subject: RE: B-2 groans (Was: B-2 Changing Colour?) This message is in MIME format. Since your mail reader does not understand this format, some or all of this message may not be legible. - ------_=_NextPart_001_01BFA4BB.292DF2E0 Content-Type: text/plain; charset="iso-8859-1" I think that discussion was about the RAM coating on the F-117, wasn't it? - -----Original Message----- From: Allen Thomson [mailto:thomsona@flash.net] Sent: April 12, 2000 3:11 PM To: skunk-works@netwrx1.com Subject: Re: B-2 groans (Was: B-2 Changing Colour?) > > B-2s skin made of carbon fiber? > > The centre is made from carbon fibres the wings are made from composite > materials/plastics. Or so they tell us (sorry I just had to say that!) > Whenever its taxying(?) you can hear it a mile off and keep waiting for it > to snap! Really? As in the B-2 creaks, groans, pops etc. loudly while the plane is rolling along? (I've never been near one of the things and wouldn't know.) BTW and just as an aside, this thread on a variable-color/colour paint job reminded me of the minor flap several years ago in which the B-2's skin was said to be very sensitive to water damage. I never quite understood that, as the plane's radar stealth obviously depends mostly on shaping. But -- and this is very, very speculative -- if there were some optical stealthiness such as a variable-color surface treatment used, that might explain the hydrophobia. A random notion in search of evidence. - ------_=_NextPart_001_01BFA4BB.292DF2E0 Content-Type: text/html; charset="iso-8859-1" RE: B-2 groans (Was: B-2 Changing Colour?)

I think that discussion was about the RAM coating on the F-117, wasn't it?

-----Original Message-----
From: Allen Thomson [mailto:thomsona@flash.net]
Sent: April 12, 2000 3:11 PM
To: skunk-works@netwrx1.com
Subject: Re: B-2 groans (Was: B-2 Changing Colour?)



> > B-2s skin made of carbon fiber?
>
> The centre is made from carbon fibres the wings are made from composite
> materials/plastics.  Or so they tell us (sorry I just had to say that!)
> Whenever its taxying(?) you can hear it a mile off and keep waiting for it
> to snap!

Really? As in the B-2 creaks, groans, pops etc. loudly while the plane is
rolling along? (I've never been near one of the things and wouldn't know.)

BTW and just as an aside, this thread on a variable-color/colour paint job
reminded me of the minor flap several years ago in which the B-2's skin was
said to be very sensitive to water damage. I never quite understood that, as
the plane's radar stealth obviously depends mostly on shaping.  But -- and
this is very, very speculative -- if there were some optical stealthiness
such as a variable-color surface treatment used, that might explain the
hydrophobia.  A random notion in search of evidence.


- ------_=_NextPart_001_01BFA4BB.292DF2E0-- ------------------------------ Date: Wed, 12 Apr 2000 23:00:15 +0100 From: "Gavin Payne" Subject: Re: B-2 Changing Colour? > > Why is it necessary to build the center (I am assuming that Gavin means the > wing spars) of carbon fibers rather than an aluminum alloy of some sort? > Would this be for weight reduction, or is it for stealth (or both)? If it is > for stealth, are there other bits that one would normally find in the wings > that are also made from composites/carbon fiber (e.g., tubing, hinges, etc.) > for this same reason? The reasons and actual structure content were a touchy subject when I was speaking to the ground crew next to their Spirit. When it was moved though they had to explain why it was creaking. I don't know too much about aircraft design however I get the impression that the centre of the aircraft is carbon fibre/aluminum where as the wings are a frame with a thin shell over them. When you look at it close up though you can see that the coating is different thicknesses depending on the locations on the surfaces. E.g. the smoother and flatter plans that are more likely to reflect radar are darker in colour. ------------------------------ Date: Wed, 12 Apr 2000 18:10:20 -0700 From: Timothy Toth Subject: Re: B-2 Changing Colour? If we assume the B-2 to use RAM (very likely). It would be normal for the aircraft to use different thicknesses AND types of RAM in different parts of the aircraft. This is due to the fact that there are a wide variety of RAMs each having different advantages/disadvantages. For example some RAM work better against radar waves coming at a high angle of incidence , some have better resistance to heat, some are more rigid/less flexible etc... And some of these RAMs have a thickness directly related to the radar wavelength they are supposed to be effective against. However all stealth aircraft also use RAS (radar absorbing structures), because some materials can be (even if marginaly) transparent to radar waves and radar waves can also induce currents in the structure of the aircraft. So a lot of the insides of the B-2 is made of low conductivity/reflectivity material (this would include tubing, hinges etc...) Of course once again just as for RAM, designers would have to take into considerations the different caracteristics of these materials (weight of course would be important). Timothy Tom wrote: Why is it necessary to build the center (I am assuming that Gavin means the wing spars) of carbon fibers rather than an aluminum alloy of some sort? Would this be for weight reduction, or is it for stealth (or both)? If it is for stealth, are there other bits that one would normally find in the wings that are also made from composites/carbon fiber (e.g., tubing, hinges, etc.) for this same reason? Gavin Payne wrote: > Why is it necessary to build the center (I am assuming that Gavin means the wing spars) of carbon fibers rather than an aluminum alloy of some sort? Would this be for weight reduction, or is it for stealth (or both)? If its for stealth, are there other bits that one would normally find in the wings that are also made from composites/carbon fiber (e.g., tubing, hinges, etc.) for this same reason?The reasons and actual structure content were a touchy subject when I wasspeaking to the ground crew next to their Spirit. When it was moved though they had to explain why it was creaking. I don't know too much about aircraft design however I get the impression that the centre of the aircraft is carbon fibre/aluminum where as the wings are a frame with a thin shell over them. When you look at it close up though you can see that the coating is different thicknesses depending on the locations on the surfaces. E.g. the smoother and flatter plans that are more likely to reflect radar are darker in colour. ------------------------------ End of skunk-works-digest V9 #27 ******************************** 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