Stealth...

Maharana

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Hope this thread would contribute in making this forum more informative.


Some information about Petr Ufimtsev:

Pyotr Yakovlevich Ufimtsev (born 1931 in Altai Krai) is a Soviet/Russian physicist and mathematician, considered the seminal force behind modern stealth aircraft technology. In the 1960s he began developing equations for predicting the reflection of electromagnetic waves from simple two-dimensional shapes.

Much of Ufimtsev's work was translated into English, and in the 1970s American Lockheed engineers began to expand upon some of his theories to create the concept of aircraft with reduced radar signatures. Northrop made extensive use of Ufimtsev's work in developing the B-2 bomber.

Developing the mathematics-

Ufimtsev became interested in describing the reflection of lasers while working in Moscow. He gained permission to do work on it after being advised that work was useless and would curtail his advancement. Because the work was considered of no military or economic value, Ufimtsev was allowed to publish his work internationally.

A stealth engineer at Lockheed, Denys Overholser, had read the publication and realized that Ufimtsev had created the mathematical theory and tools to do finite analysis of radar reflection. This discovery inspired and had a big role in the design of the first true stealth aircraft, the Lockheed F-117. Northrop also used Ufimtsev's work to program super computers to predict the radar reflection of the B-2 bomber.

In the 1960s Ufimtsev began developing a high-frequency asymptotic theory for predicting the scattering of electromagnetic waves from two-dimensional and three-dimensional objects. Among such objects were the finite size bodies of revolution (disk, finite cylinder with flat bases, finite cone, finite paraboloid, spherical segment, finite thin wire). This theory is now well known as the Physical Theory of Diffraction (PTD).

The first results of PTD were collected in the book: P.Ya. Ufimtsev, Method of Edge Waves in the Physical Theory of Diffraction, Soviet Radio, Moscow, 1962. In 1971 this book was translated into English with the same title by U.S. Air Force, Foreign Technology Division (National Air Intelligence Center ), Wright-Patterson AFB, OH, 1971. Technical Report AD 733203, Defense Technical Information Center of USA, Cameron Station, Alexandria, VA, 22304-6145, USA.

According to the following publications, this theory played a critical role in the design of American stealth-aircraft F-117 and B-2

- Ufimtsev, P.Ya. Theory of Edge Diffraction in Electromagnetics, Tech Science Press, Encino, California, 2003.
- Ufimtsev, P.Ya. Fundamentals of the Physical Theory of Diffraction, Wiley & Sons, Inc., Hoboken, New Jersey, 2007.


In these two books, P.Ya. Ufimtsev presented the further development and application of PTD and its validation by the exact mathematical theory. In particular, a new version of PTD, based on the concept of elementary edge waves, is presented in his book Fundamentals of the Physical Theory of Diffraction (2007). With appropriate modifications the modern PTD can be utilized for the solution to many practical problems. Among them are the design of microwave antennas, mobile radio communication, construction of acoustic barriers to decrease a noise level, evaluation of radar cross sections for large objects (tanks, ships, missiles, etc.).

Dr. Ufimtsev has been affiliated with a number of research and academic institutions, including the Institute of Radio Engineering and Electronics of the USSR Academy of Sciences (Moscow), Moscow Aviation Institute, the University of California (Los Angeles, Irvine) and most recently, the Moscow State University (Russia, 2007) and the Siena University (Italy, 2008). Currently he is a retiree and a consultant in the field of electromagnetics. Among his honors and awards are the USSR State Prize and the Leroy Randle Grumman Medal.

Ufimtsev taught at the University of California, Los Angeles (UCLA), which is the same school that Ben Rich, developer of the F-117 "Stealth Fighter", studied for his graduate degree.

Regards.
 
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W.G.Ewald

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The Germans were very early into stealth technology!

Stealth aircraft - Wikipedia, the free encyclopedia
During World War I, an attempt to reduce the visibility of military aircraft through the experimental use of "Cellon" plastic transparent covering material resulted in single examples of the Fokker E.III Eindecker fighter monoplane, the Albatros C.I two-seat observation biplane, and one German heavy bomber design, the Linke-Hofmann R.I all being covered with the "Cellon" material; the latter two aircraft had all-wooden structures covered with the "Cellon" material, which degraded rapidly in direct sunlight and were not proceeded with any further.
 

aerokan

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Maharana

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Guys, seriously funny ^^:laugh:

I believe that the modern stealth technology was introduced by the Nighthawk but a Russian Dr. Ufimtsev actually developed the concepts which are today pioneered by the Raptor, B-2 spirit & the PAK FA as well.

Wiki says - Stealth aircraft are aircraft that use stealth technology to avoid detection by employing a combination of features to interfere with radar as well as reduce visibility in the infrared, visual, audio, and radio frequency (RF) spectrum.

The Germans were very early into stealth technology!

Stealth aircraft - Wikipedia, the free encyclopedia
During World War I, an attempt to reduce the visibility of military aircraft through the experimental use of "Cellon" plastic transparent covering material resulted in single examples of the Fokker E.III Eindecker fighter monoplane, the Albatros C.I two-seat observation biplane, and one German heavy bomber design, the Linke-Hofmann R.I all being covered with the "Cellon" material; the latter two aircraft had all-wooden structures covered with the "Cellon" material, which degraded rapidly in direct sunlight and were not proceeded with any further.
@W.G.Ewald

Sir, I agree that the above example has much more to do with invisibility to a human eye. Please throw some more light on modern stealth as well which has much more to do with the invisibility to the radar not just with angles to deflect radar waves but also with the flying wing concept.

More on German research in the Flying Wing concept :-

Hugo Junkers patented a wing-only air transport concept in 1910. He saw it as a natural solution to the problem of building an airliner large enough to carry a reasonable passenger load and enough fuel to cross the Atlantic in regular service. He believed that the flying wing's potentially large internal volume and low drag made it an obvious design for this role. In 1919 he started work on his "Giant" JG1 design, intended to seat passengers within thick wings, but two years later the Allied Aeronautical Commission of Control ordered the incomplete JG1 destroyed for exceeding post-war size limits on German aircraft. Junkers conceived futuristic flying wings for up to 1,000 passengers; the nearest this came to realization was in the 1931 Junkers G-38 34-seater Grossflugzeug airliner which featured a large thick-chord wing providing space for fuel, engines and two passenger cabins.

A more serious attempt at "invisibility" was tried with the Horten Ho 229 flying wing fighter-bomber, developed in Germany during the last years of World War II. In addition to the aircraft's shape, which may not have been a deliberate attempt to affect radar deflection, the majority of the Ho 229's wooden skin was bonded together using carbon-impregnated plywood resins designed with the purported intention of absorbing radar waves.

Testing performed in early 2009 by the Northrop-Grumman Corporation established that this compound, along with the aircraft's shape, would have rendered the Ho 229 virtually invisible to the top-end HF-band, 20-30 MHz primary signals of Britain's Chain Home early warning radar, provided the aircraft was traveling at high speed (approximately 550 mph (890 km/h)) at extremely low altitude (50–100 feet).

In the closing weeks of WWII the US military initiated "Operation Paperclip", an effort by the US Army to capture as much advanced German weapons research as possible, and also to deny that research to advancing Soviet troops. A Horten glider and the nearly complete Ho 229 V3 third prototype airframe were secured and sent to Northrop Aviation for evaluation in the United States, who much later used a flying wing design for the B-2 stealth bomber.
Regards.
 

W.G.Ewald

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Wonder Woman's Invisible Plane

 

Maharana

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The Grand Daddy of the flying wing stealth -




And here's the modern avatar of that--


Regards..
 
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