Faceting for stealth shown in open literature before F-117 unveiling

The first mention I recall of faceting was in Bill Sweetman's "Stealth Aircraft" around 1986/87 ish?
 
Very interesting, thanks Paul.

I have some conceptual drawings from Bill Gunston from the same decade and he always show smooth designs with a "Northrop look". I didn't discovered faceting until I saw the first F-117 pic.
 
AIAA-81-1506
Combat Survivability with Advanced Aircraft Propulsion Development

L.W. Throndson, Naval Weapons Center, China Lake, CA

Thanks for great finding, Overscan!
 
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Remembering these well-known faceted pieces of wood that were presented to firsts F-117 pilots as memorabilia to mask all the cross reference between faceting LO technology and actual airfrimes, i wonder how Mr. Throndson was faceted after this obvious leak.
 
I bet I've seen recently Varieze-based RPV(?) with significant faceting of forward fuselage from the mid-80s, but still can't find image in my 2Tb of stuff...
 
Wow... that paper being on the loose must have given people nasty moments, although fortunately most of the facets are pointed in exactly the wrong direction.

The Long-Eze thing was the Scaled Composites Model 144 aka California Microwave CM-44, IIRC...
 
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Isn't the Long EZ made out of fiberglass and foam core (at least the original ones)? you should be able to see right through it with radar and get reflections off the internal reflective components (me thinks). Furthermore, I think the prop and other non-aligned parts of the airframe would swamp whatever benefit you could get with faceting just the nose.
So what's with the curious shape of the nose? was it something related to the purpose of the testbed? ???
 
overscan said:
I wonder if that sketch inspired Italeri's MiG-37 Ferret-E?
Click to expand...

I asked to myself the same thing....

It really looks like the "Ferret-E" model (I received it as gift for my birthday, long long ago back in the glamorous 80s).
 
AeroFranz said:
Isn't the Long EZ made out of fiberglass and foam core (at least the original ones)? you should be able to see right through it with radar and get reflections off the internal reflective components (me thinks). Furthermore, I think the prop and other non-aligned parts of the airframe would swamp whatever benefit you could get with faceting just the nose.
So what's with the curious shape of the nose? was it something related to the purpose of the testbed? ???
Click to expand...

Could it be a window for a camera?
 
There was a book, I believe called "Stealth" that had a blue cover on it that was published in the 86ish timeframe I believe. While the other books had mainly stuck to the curved surfaces idea, this one had stated that it believed the (F-117A) was faceted, and not curved.
 
I always wondered what the reaction was when the faceted Lampryidae airframe was seen in MBB hangers during prototyping.
 
firepilot said:
There was a book, I believe called "Stealth" that had a blue cover on it that was published in the 86ish timeframe I believe. While the other books had mainly stuck to the curved surfaces idea, this one had stated that it believed the (F-117A) was faceted, and not curved.
Click to expand...

Yes, this was by Bill Sweetman and was the first time I read about faceting, as I posted earlier in the topic. The picture I posted was however from an unclassified article from 5 years previous to that.

Interestingly L.W. Throndson was previously at Rockwell - this faceted concept having some conceptual commonality to the Rockwell "Surprise Fighter" design.

surprise-fighter-pole-shots-1973_0005-jpg.174149
 
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Thanks, I could not remember who wrote it, and it had been a long time since I have seen a copy of it.
 
According to the designer of lampyridae, any physicist during the past 100 years could have worked the basic principles of facet stealth. The trick is to apply it to something that could fly.
 
ISTR hearing about a book by a Soviet designer, maybe from the '60s, regarding stealth and I think it discussed faceting. also, not that I have ever heard it referred to faceted surfaces, but the fictional Firefox from the movie has a faceted nose section, and the movie was made in '81 and released in '82. I guess you could also say the fictional Blue Thunder helo from the movie used faceted surfaces and it was released in '83.
 
famvburg said:
ISTR hearing about a book by a Soviet designer, maybe from the '60s, regarding stealth and I think it discussed faceting. also, not that I have ever heard it referred to faceted surfaces, but the fictional Firefox from the movie has a faceted nose section, and the movie was made in '81 and released in '82. I guess you could also say the fictional Blue Thunder helo from the movie used faceted surfaces and it was released in '83.
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With regards to Firefox, I believe the design of the movie aircraft was aided by engineers from Northrop explaining some features such an aircraft might have, IIRC. As for Blue Thunder, I don't think the panels had anything to do with stealth and everything to do with making a relatively low cost movie helo.
 
According to at least one magazine article, input from Lockheed engineers.
 
Also, probably, since it was using technology related to the Apache and the Apache had flat surfaces.
 
Sorry - I can't cite a reference for this but I seem to recall reading somewhere that the Germans faceted the tops of periscopes in an attempt to defeat Allied radar. Anyone else remember this?
 
AeroFranz said:
Isn't the Long EZ made out of fiberglass and foam core (at least the original ones)? you should be able to see right through it with radar and get reflections off the internal reflective components (me thinks). Furthermore, I think the prop and other non-aligned parts of the airframe would swamp whatever benefit you could get with faceting just the nose.
So what's with the curious shape of the nose? was it something related to the purpose of the testbed? ???
Click to expand...
Funny thing is the EZ owes itself to fiberglass being transparent to radar, in a way.


That Jiran made aircraft was intended to fly over China and 'sniff' their nuclear particles. Rutan had a very minor hand in it, and its one of the things that convinced him of foam and fiberglass being viable for aircraft.
 
overscan (PaulMM) said:
firepilot said:
There was a book, I believe called "Stealth" that had a blue cover on it that was published in the 86ish timeframe I believe. While the other books had mainly stuck to the curved surfaces idea, this one had stated that it believed the (F-117A) was faceted, and not curved.
Click to expand...

Yes, this was by Bill Sweetman and was the first time I read about faceting, as I posted earlier in the topic. The picture I posted was however from an unclassified article from 5 years previous to that.

Interestingly L.W. Throndson was previously at Rockwell - this faceted concept having some conceptual commonality to the Rockwell "Surprise Fighter" design.
Click to expand...
Nice find. Rockwell seemed to forget about this when they entered the ATF program and basically borrowed b1 era stealth
 
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rooster said:
overscan (PaulMM) said:
firepilot said:
There was a book, I believe called "Stealth" that had a blue cover on it that was published in the 86ish timeframe I believe. While the other books had mainly stuck to the curved surfaces idea, this one had stated that it believed the (F-117A) was faceted, and not curved.
Click to expand...

Yes, this was by Bill Sweetman and was the first time I read about faceting, as I posted earlier in the topic. The picture I posted was however from an unclassified article from 5 years previous to that.

Interestingly L.W. Throndson was previously at Rockwell - this faceted concept having some conceptual commonality to the Rockwell "Surprise Fighter" design.
Click to expand...
Nice find. Rockwell seemed to forget about this when they entered the ATF program and basically borrowed b1 era stealth
Click to expand...
Initial requirements for ATF were not that high for RCS, doable with a bit of B-1 era stealth and some careful avoidance of big spikes in the front quarter. The published Rockwell ATF design is from this era. Then Lockheed and Northrop convinced USAF a truly stealthy ATF was possible, and the requirement was changed. Rockwell's design was significantly revised for this, but this version remains unseen.
 
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Aerodynamic and Inlet Flow Characteristics of Several Hypersonic Airbreathing Missile Concepts
James L. Dillon , Don C. Marcum Jr. , Patrick J. Johnston and James L. Hunt
Journal of Aircraft
Volume 18, Issue 4
July 1981

This shape was the result of a parametric study aimed at
simultaneously achieving high aerodynamic performance
(L/D<<4.0), good volumetric efficiency (K2/5/<<0.23) and
stealth in a vehicle designed for long-range cruise at Mach 6.
Click to expand...
 

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This is hardly surprising. When I worked in LO, a lot of the science being used was from Soviet journals. This was somewhat ironic in a highly classified USArmy program
 

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