Sukhoi S-37 "Berkut"(Possible Plasma Based Stealth ?)

Main competitor-colleague of Mikoyan-Gurevich Design Bureau is the Sukhoi Design Bureau which was able to create, develop, build, and start testing of the 5th generation fighter in just 10 years comparing to MFIs long 15 years. This aircraft is called S-37 Berkut [Ber-koot]. The configuration of forward-swept wings combined with canard wings can be compared to the American X-29. This configuration makes the aircraft more stealthier and maneuverable. Powerplants are temporarily taken from the Mig-31 as Russian 5th generation powerplants will not enter service until 2005(?) (no one can chase Sukhoi in advanced design). Very little is known about this aircraft but a few pictures of the Berkut have been released. The aircraft which probably gets most of its stealth capability from its paint and (rumour has it) the electro - magnetic plasma field around the aircraft. This technology is one of the most closely guarded secrets of the Russian Airforce and details are not published yet. However I found this article and re-produce it below.

Russian Plasma-Based Stealth?
Better, Cheaper Than US Version?

The following is an alleged Russian ITAR-TASS agency release about a new way of obtaining stealthiness, via the use of "plasma". They say that it is or will be far better than the US Lockheed Skunk Works or Northrop versions.

By Nicolai Novichkov

ITAR-TASS Information Agency
Moscow, January 20, 1999
Translation by Philip Kaploun

Research team at the Research Center named after M.V. Keldysh has developed new technologies allowing dramatic decrease in aircrafts' radar observability. Russian approach to low observability (LO) technologies is completely different from US Stealth and offers complete furtiveness of the protected object at a significantly lower price. An exclusive interview about these technologies was conducted by Nicolai Novichkov, ITAR-TASS with director of the Center, academic of Russian Scientific Academy Anatoliy Korteev.

As academic explained, American approach to LO (Stealth technology) applied on B-2, F-117A, and fifth generation fighter F-22 "Raptor" is based on the following principles. The airframes of these aircrafts are designed to minimize their radar cross section (RCS), avoid all possible elements of the structure, which could reflect electromagnetic radiation. In order to minimize reflected radiation radio absorbing materials (RAM) are also applied to the surface of the structure. The main drawbacks of the Stealth technology are its negative effects on the flight and agility characteristics of the stealth aircrafts.

Russian scientists approach the issue from the other direction. They proposed to create a plasma formation around protected object, which prevents radars from seeing it. Thus, aerodynamical characteristics of the plane itself do not suffer. Without interfereing with technical characteristics the artificially created plasma cloud surrounding the plane guarantees more than hundred times decrease in its observability.

The physics of plasma protection can be described as following. If an object is surrounded by a cloud of plasma, several phenomenas are observed when the cloud interacts with electromagnetic waves radiated by enemy radar. First, an absorption of electromagnetic energy occurs in the cloud, since during plasma penetration it interacts with plasma charged particles, pass onto them a portion of its energy, and fades. Second, due to specific physical processes, electromagnetic wave tends to pass around plasma cloud. Both of these phenomenas results in dramatic decrease of the reflected signal.

Static and flight experiments proved the effectiveness of this technology. The first generation devices, producing plasma field surrounding an aircraft and decreasing reflected signal were created in the Center. Later, a possibily of creating second generation advanced systems (capable of not only decreasing reflected signal and changing its wavelength, but also producing some false signals) was discovered. Such systems significantly complicate determination of actual aircraft's speed, its location and leads to development of completely new approaches to LO provision, unachievable to conventional Stealth technology. Furthermore, the weight of the systems developed in Russia do not exeed 100 kg, and power consumption ranges from kilowatts to tens of kilowatts.

Advances in development of the third generation LO systems allowed to clear the systems of first and second generation for export, commented academic Anatoliy Korteev.

26/01/99 (c) ITAR-TASS,

Below are 4 views of the Berkut S-37 kindly supplied to me by Peter Whitman to whom I am very grateful. Thanks Pete, and to everyone who contributes, without whose help I could not keep site up to date.