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25.03.2002 16:58:20
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ВВС;
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Вопрос по "плазменному стэлсу"
Мое почтение!
Никаких статей на эту тему в российской прессе небыло последнее время? В Джейнс статей 15 нашел, но ничего подробного. Упоминается в этом отношении МиГ-31, 1.42/44, Тополь-М, какие-то китайские разработки Ченгду. Также, боинговский Фантом Воркс работает над плазменным генератором для самолетов.
Одна интересная статья попалась о сотрудничестве между Россией в Великобританией в области генераторов плазмы для самолетов в целях снижения радарной заметности и улучшения аэродинамических качеств:
"Russian-UK partnership in plasma power
Russian scientists have stunned a select group of Western physicists by claiming they have stumbled on a breakthrough in plasma
technology with the potential to reduce aircraft drag not merely by a few per cent but by as much as 30 per cent - maybe more. A plasma is an ionised gas. Run an electric current through a neon light tube, for example, and the end result is a plasma. Another common plasma is found in lightning. The claims are being publicised not by the Russians, but by BAe. Representatives from BAe have visited many previously uncharted former Soviet science establishments over the past five years in the search for innovative science and technology. Having 'found' the plasma research, BAe is seeking to validate the claims in laboratory experiments of its own. The experiments involve the introduction of a plasma or ionised gas into the airstream in front of an aircraft. If BAe can substantiate Russia's claims - and there is considerable scepticism that there is anything measurably real about the Russian work - it could lead to one of the biggest leaps in aircraft design since the coming of the jet age. According to the Russians, the potential advantages of 'plasma erodynamics' are not even limited to drag reduction. Other spin-offs include: sonic boom attenuation - delaying the onset of an aircraft's supersonic shockwave; aerodynamic control through selective drag reduction - allowing an aircraft or missile to manoeuvre by applying the plasma effect to different parts of the airframe; and thermal protection through reduced air friction.
It could also herald a breakthrough in stealth, since plasma generation is claimed vastly to reduce radar cross-section. The absorption of radio waves by plasmas has been well-known since the early days of manned space flight. The communications black-out that a space vehicle encounters on re-entry is caused by the shielding effects of plasma. This builds naturally in front of the spacecraft as it hits the
Earth's atmosphere and shocks the air to high temperature. The same principle applies to the absorption of radar energy. Although the aircraft would appear to glow like a lightbulb, with enough plasma generators to cover the entire airframe, it could be rendered totally invisible to radar. The story of how Russia's plasma research came to reside at BAe began in the early 1990s. For some years, the UK MoD and elements of the UK aerospace industry had been aware of the potentially beneficial effects of plasmas on airframe design; low-key
experiments, indeed, had been conducted in the UK in the early 1980s. Following the collapse of the Soviet Union in 1991, BAe struck an agreement with a Russian government agency charged with realising commercial benefit from the sale or licensing of technology and products developed under former Soviet space, aerospace and defence programmes. The accord was supposed to lead to synergies that would benefit both parties.
The deal broke down as the Russians tried to sell verything "from night sights to jet engines", according to one UK official, and the Russian market was soon found to be almost worthless due to the dire state of the economy. However, the premise was deemed sound.
All it needed, BAe officials concluded, was some focus. In 1993, BAe headquarters asked its Bristol-based Sowerby Research Centre (SRC) to lead the company's research-gathering project in Russia and other countries of the CIS. The SRC chose Professor Ron McEwen, executive scientist at the Bristol centre, to head the programme. He was familiar with aspects of Soviet fundamental science after visits to several recently opened 'science cities' in the Moscow area and contacts with Russian scientists at a high-technology exchange forum in Finland. The new, refocused BAe charter was now clear. One of its twofold aims was "to enable the acquisition of former Soviet technologies, materials, processes, products or facilities relevant to any aspect of BAe operations when this would be more cost-effective than by other means available to us". Among other potentially beneficial technologies, BAe has been looking at former
Soviet techniques for welding aircraft primary structures, a technique scoffed at by the rest of the world, but for which the Russians are
claiming weight savings of up to 40 per cent. With its partners, BAe is also evaluating new Russian-developed aluminium alloys. Russia
developed the world's first aluminium-lithium alloys, a material that has contributed much to the aerospace industry. It was, however, the
second aspect of the BAe charter that proved instrumental in the plasma discovery. This objective was "to investigate claims of hitherto
unknown former Soviet capabilities where these appear to offer the possibility of technical advantage".
Prof McEwen began trawling Russia in 1994. He initially enquired about possible scientific breakthroughs at intermediate levels -
university directors - descending deeper as his investigation went on into individual departments. "I became well-known within the Moscow
region, so much so that people started coming to me," he said. He began to pick up rumours that the Russians had been conducting
exotic experiments with plasmas in the aerospace field. "They're complicated, a bit difficult to control and understand, though a lot is
understood, especially about relatively low-temperature plasmas," said Prof McEwen. Intriguingly, the Russians maintained they had
developed "special plasmas" that behaved differently at high pressures, when they are normally difficult to sustain. To garner Prof
McEwen's interest, a director of one particular institute demonstrated the effect with a portable, box-like device from which a jet of plasma
would shoot out and punch a hole through a razor-blade. The Russians maintained that the technology was semi-secret and that it had
potential applications in the anti-ballistic missile field and within supersonic combustion ramjets (scramjets) for hypersonic aircraft. Prof
McEwen, however, was unimpressed. Besides the sideshow atmosphere, BAe had no interest in either application. The effect was
sufficiently interesting, however, for him to commission a Russian scientist to write a review of all unclassified Soviet work in the plasma
field. When complete, the company realised it possessed what was probably the first truly authoritative account of Russian work on
plasmas. It documented papers that promised massive drag reductions by applying plasmas to flying vehicles.
"Normally, aerodynamicists can design the shape of a flying vehicle to suit the range of atmospheric conditions, speeds and so on that it
will experience," Prof McEwen said. "They assume there is nothing they can do about the atmosphere itself. The Russian approach, on
the other hand, seeks to alter the atmosphere through which the vehicle is flying." An important parameter is the speed of sound, which
depends on the temperature and the specific heats of the gas. Specific heats are in turn related to the complexity of the molecules
comprising the gas The gas laws themselves depend on the forces between the molecules. If some of the molecules are not just N2 and
O2 - the usual constituents of air - but more complex ones, or if there are unusual forces between them, the result is an atmosphere
modified from the norm and this will alter the aerodynamics of a body flying throug hit. The question, according to Prof McEwen, is: "What
are the details and how can it be made to work to our advantage?" He returned to Russia in 1996 with academic and company
aerodynamic experts. Mainly sceptical, they were keen to take a more in-depth look at the Russians' so-called 'special' plasmas.
Previous experiments conducted at TsAGI - the Central Aerodynamics and Hydrodynamics Institute outside Moscow - had shown drag
reductions, but these had explored conditions not of immediate interest to BAe. A further set of experiments was set up under the
auspices of BAe Military Aircraft, Sowerby Research Centre, the UK MoD and DERA. While BAe was mainly interested in plasma
application to aircraft for high-subsonic/low-supersonic, medium-altitude flight - the regime in which most of its military and civil products
fly - DERA was keen to evaluate its wider implications, and for hypersonic flight in particular. The Russians themselves were stressing the
potential application of plasmas at high altitudes and speeds at, or in excess of, Mach 5.
In the series of UK-sponsored tests run at TsAGI at the end of 1996, drag reductions were again noted. About this time, BAe and DERA
became aware of a growing interest in this topic in the USA and were invited to participate in an expert meeting in Colorado last June.
Although many US delegates attended, little focused research had apparently been conducted in the USA until then. The work by BAe
and DERA in collaboration with the Russians made the US community take notice. That the USA is interested in the potential of plasma
aerodynamics is beyond doubt. US officials said that a "major meeting" on the subject has since been held at Princeton University, New
Jersey, and more recently at Norfolk, Virginia. Furthermore, US plasma experiments have been carried out, some of them replicating the
Russian tests. However, the conclusions drawn from their work so far are by no means clear. At NASA's Langley Research Center, the
focus of renewed US hypersonic activity, scepticism about the value of plasma aerodynamics abounds. "There is no smoking gun," said
Dennis Bushnell, senior scientist at the facility. "There is no phenomenon here. What we have are experimental observations only. Ifthere's anything in it, then there's no defensible theory."
Bushnell conceded that US experiments have recorded an effect - a drop in drag - and that the Russian work is "worth investigating and
running to ground". He is dismissive, however, of the measurement techniques that the Russians have used to analyse this "plasma
magic", as he calls it. "Besides, even if there is an effect, what do you do with it?" he asked. "Is there any new physics here? Even if there
is, there's the whole issue of how you make use of it." One concern is that the energy needed to generate a sufficiently workable plasma
may out weigh the energy savings that may accrue from a few percentage points in drag reduction. US experiments into plasma
aerodynamics are likely to continue for at least another 18 months, according to US officials, under the aegis of the USAF's Wright
Laboratory at Wright-Patterson AFB, Ohio, at NASA and within the Air Force Office of Scientific Research.
Part of the rationale for BAe's decision to go public on its plasma co-operation with the Russians is borne of the desire to do more work
with the USA. The nightmare scenario for any sophisticated aerospace nation, the UK included, is that a breakthrough in this field by
another country could render its current technology obsolete. A number of plasma experiments, heavily based on Russian work, are
continuing at BAe's Warton facility in Lancashire. BAe's Prof McEwen is philosophical about all that he has observed to date. "Are the
Russians achieving anything other than dumping heat into the airstream?" he asked. "There certainly are effects we just can't explain at
the moment and we have to continue our investigations until things become clearer. No-one, not even the Russians, has successfully
exploited the technology. Yet it does seem to have the potential to yield aerodynamic advantage." 7.4.2 Proposed partnership with UK on
new naval CIWS for export
Russia's Altair State Research and Development Corporation is seeking sponsors for the Trezubets (Trident) rocket-based close-in
weapon system that it has under development. According to Altair officials, the organization has approached both BAe Defence and GEC-Marconi
concerning possible collaboration, with particular reference to potential Far East markets. Trezubets would marry a novel dual-frequency
I/J-band (2/3cm) radar with a total weight of 5,000kg, with one or more 10-round trainable launchers, which also weigh 5,000kg
each. These are automatically reloaded with replacement five-round rocket pods mounted on below-deck carousels. System power
consumption is 20kW.The launchers fire proximity-fuzed unguided rockets having a maximum range of 1,500m. System reaction time is
2s. Altair has been developing a prototype of the mechanically scanned radar for the past two years. The scan rate of one sweep per
second during surveillance rises to six per second in tracking mode, which is said to make the design the fastest of its kind. The radar is
claimed to be capable of tracking 16 air targets simultaneously, even in the presence of intensive jamming (ECM suppression 80dB).
Coverage in elevation is -5 to +70 , and detection range is 30km against a 1m2 target. No Trezubets launcher has yet been constructed,
but the folding-fin rockets are based on an existing design. These have a nominal velocity of 1,000m/s, resulting in a flight time of 1.5s to
intercept range. Each of the 220mm-calibre rockets weighs 60kg, is 1.7m long and carries a heavy (25kg) warhead. Company literature
indicates that a single Trezubets launcher would provide a kill probability of 0.9 or greater at a range of 1,500m against each of four
missiles in a wave, assuming that the incoming weapons are flying along the same axis at intervals of 2s. Altair representatives state that
a kill against a Harpoon or anti-radiation missile could be virtually guaranteed by ripple-firing six rockets in a controlled-dispersion pattern."
С уважением, Venik