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Re: Caça de 5a geração chinês

Enviado: Qui Jan 13, 2011 3:17 pm
por kekosam
Luís Henrique escreveu:E essas fotos com o mesmo caminhão. Chegaram a qual conclusão? Qual o tamanho da criança???
Ninguém respondeu??? Falta de educação. :evil:

Calculando, por trigonometria, aparenta ser, aproximadamente, 50% maior que o J-10.

Re: Caça de 5a geração chinês

Enviado: Qui Jan 13, 2011 4:05 pm
por Carlos Lima
Marino escreveu:EUA admitem apreensão com avião chinês

Denise Chrispim Marin

Os EUA expressaram ontem séria preocupação com o investimento da China na produção do J-20, supercaça invisível aos radares, e de outros equipamentos militares sofisticados. O chefe das Forças Armadas americanas, almirante Mike Mullen, afirmou ter se surpreendido com as imagens do primeiro teste de voo do J-20, na terça-feira, realizado poucas horas antes do encontro entre o secretário de Defesa, Robert Gates, com o presidente da China, Hu Jintao, em Pequim.

"A questão sempre presente é: por quê? Sei que a China tem seus próprios desafios, como um país emergente com influência global, e têm todo o direito de desenvolver sua capacidade de defender seus interesses, assim como os EUA", declarou. "Mas muitas dessas capacidades parecem estar focadas nos EUA", completou Mullen.

O teste do J-20 reduziu as chances de o governo americano extrair de Pequim um compromisso de diálogo na área militar. Esse seria um dos pontos fortes da visita de Hu ao presidente americano, Barack Obama, na semana que vem, em Washington. Mullen ressaltou que esse seria o tema "mais importante" da pauta bilateral, assim como o diálogo na área econômica.

Ao reiterar a posição americana em favor de maior pressão da comunidade internacional sobre a Coreia do Norte, o almirante chamou a atenção para o papel da China na garantia da paz na região.

Pequim é contra a adoção de novas sanções contra Pyongyang e prefere a via diplomática. "As provocações (entre as duas Coreias) podem se tornar catastróficas e a China tem grande responsabilidade nisso", afirmou Mullen.

O cronograma do J-20 prevê que os primeiros aviões serão entregues em maio de 2017. A aeronave atinge cerca de 2.200 quilômetros por hora e tem capacidade de manter-se em velocidade supersônica por um longo período.
O nome disso é...

Mais $$$$$$$$$$$$$ para o F-35 e quem sabe até a ressureição do F-22... :wink:

Os Japoneses que o digam...

[029]
[]s
CB_Lima

Re: Caça de 5a geração chinês

Enviado: Qui Jan 13, 2011 6:47 pm
por Penguin
Muito interessante análise:
Ares
A Defense Technology Blog

J-20s Stealth Signature Poses Interesting Unknowns
Posted by David A. Fulghum at 1/13/2011 10:01 AM CST
David Fulghum and Bill Sweetman/Washington

Anti-stealth and stealth detection technologies will bring into question all stealth designs, including China’s new J-20. How much invulnerability will current low-observability techniques retain as air defense systems adopt even larger and more powerful active, electronically scanned array (AESA) radars?

Airborne detection of stealth aircraft may already be an operational capability. Raytheon’s family of X-band airborne AESA radar family (in particular those on upgraded F-15Cs stationed in Okinawa) can detect small, low-signature cruise missiles. Moreover, Northrop Grumman’s lower-frequency, L-band AESA radar on Australia’s Wedgetail airborne early warning and control aircraft is larger and potentially more capable of detecting stealth aircraft at longer ranges.

Better images emerging from China point clearly to the J-20’s use of stealth technology, but there are still major uncertainties and unanswered questions.

The overall shape resembles that of the F-35 and F-22, with a single “chine line” uniting the forebody, upper inlet lips and wing and canard edges, a curved surface above that line and flat, canted body surfaces below it. The wing and canard edges are aligned – the wing and canard leading edges are parallel and the trailing edge of the canard is aligned with the opposite wing trailing edge. The same basic philosophy has also been adopted in British, Swedish and Japanese studies for stealth fighters.

The aim in all cases is to endow a practical, agile fighter configuration with a “bow-tie” radar signature, with the smallest signature around the nose and the greatest (still much lower than that of a conventional aircraft with curved or vertical-slab sides) to the side. The fighter’s mission planning system, using a database of known radar locations, then derives a “blue line” track that weaves between radars and avoids exposing the side-on signature to those radars more than transiently.

The diverterless supersonic inlet avoids a signature problem caused by a conventional boundary layer diverter plate – the F-22 has a conventional inlet, which is likely to require extensive radar absorbent material (RAM) treatment.

The biggest uncertainty about the design concerns the engine exhausts, which as seen on the prototype are likely to cause a radar cross-section (RCS) peak from the rear aspect. One possibility is that a stealthier two-dimensional nozzle will be integrated later in the program: however, the nozzles on the current aircraft show some signs of RCS-reducing saw-tooth treatment, suggesting that the PLA has accepted a rear-aspect RCS penalty rather than the much greater weight and complexity of 2-D nozzles.

Other details of the design are unknowns. Stealth development has been dogged by detail design challenges. All the antennas on the aircraft have to be flush with the skin and covered with surfaces that retain stealth properties while being transparent in a specific frequency. Maintainability becomes a complex trade-off: some systems requiring frequent attention will be accessed via landing gear and weapon bays, and others by latched and actuated doors that can opened and closed without affecting RCS, but the latter are a heavy solution.

Perhaps the toughest challenge in stealth design is the need to manage RF surface currents over the skin. Early stealth designs used heavy, maintenance intensive RAM. The F-22 introduced a much lighter surface treatment, but it has proven unexpectedly difficult to maintain, causing corrosion issues. Lockheed Martin now claims that the F-35 will be robust and affordable to maintain in service, with a combination of a high-toughness sprayed-on topcoat and a conductive layer cured into composite skin panels.

The Chengdu J-20 design has struck many analysts and observers as familiar and somewhat different that the Lockheed-Martin F-22, F-35 or the Sukhoi T-50.

“The J-20 is reminiscent of the Russian MiG 1.42 both in terms of planform, and also with regard to the rear fuselage configuration,” says Douglas Barrie, senior fellow for military aerospace at London’s International Institute for Strategic Studies. “The most obvious difference is the greater forward fuselage shaping as the basis for low observable characteristics, along with the different engine intake configuration. The MiG program was cancelled by the Russian government around 1997.” However, the similarity to the MiG concept may suggest some collusion with the Russian aviation industry.

Re: Caça de 5a geração chinês

Enviado: Sex Jan 14, 2011 11:02 am
por marcelo l.
http://en.rian.ru/analysis/20101229/161986565.html

Both experts and amateurs who have studied the blurred photos of an unfamiliar fighter jet on a runway in China (http://china-defense.blogspot.com/2010/ ... rious.html) have concluded that Beijing has started testing its fifth-generation stealth fighter.
The J-20 prototype is expected to rival the U.S. F-22 and the Russian T-50 fighters. But is China ready to start mass-producing the aircraft? How good is the prototype?
Experts call it a combination of the Russian and U.S. fifth-generation fighters, but that greatly simplifies matters. In the last 20 years, China has been working closely with Russia to develop a modern fighter jet. But the J-20 is not simply a copy of a Russian design. Rather China has tried to build a completely new aircraft based on the technology and knowledge it has gained during its years of cooperation with Russia.
The future of the new Chinese fighter will depend on several factors.
Engine
It is not clear what kind of engine the plane will have. Some say it will use the prospective Chinese-made WS-15 engine with a maximum thrust exceeding 18,000 kg, but the engine is still in the pipeline.
China has been unable to reproduce Russia's highly efficient high-temperature turbofan AL-31F engine, designed in the early 1980s and currently mounted on the Su-27 fighter and its modifications. The engines for Sukhoi planes manufactured in China are made in Russia and then assembled and adjusted in China.
The AL-31F engine is also mounted on China's J-10 fighter planes. The engine's Chinese analogue, the WS-10, is less efficient than the Russian prototype.
Materials
A fifth-generation stealth fighter must be able to evade radar, and so it must be made from modern composite materials. However, China does not produce such materials in commercial amounts, and experts doubt that it can develop and produce them for its Air Force.
Electronics
Electronic equipment, primarily radar, in China stands at approximately the same level as its engines. Chinese designs fall short of the capabilities of their Russian, European and American counterparts. Although China has been gradually narrowing the gap, it still has to import modern electronic equipment for its aircraft.
The best aircraft radar systems are currently made for Russia's Su-30MKK fighters, and China will most likely copy this design. It is not clear how much it will differ in terms of specifications from next-generation Russian or American radar systems.
Weapons
The guided weapons used in the Chinese Air Force were mostly copied from U.S., Israeli and Russian prototypes made in the 1960s through 1980s. China will have to spend a great deal of time and effort to develop its own weapons, even if it borrows elements of prototypes bought from other countries. But foreign producers are becoming increasingly wary of sharing their next-generation technology with China.
Conclusions
Since the 1970s, China has consistently lagged 15 to 20 years behind the world leaders in aircraft manufacturing. This was true of their third- and fourth-generation aircraft, and this appears to be the case with its fifth-generation fighter plane.
The J-20 fighter was produced nearly 20 year after the U.S. YF-22 (the prototype of the mass-produced F-22A), 17 years after the Russian MiG-1.44 (MiG-MFI, or Multifunctional Frontline Fighter), and 14 after Russia's S.37 (Su-47).
If the J-20 is accepted as the prototype for a new series, China will be able to produce a fifth-generation fighter plane within 10 years. If not, it will begin batch production no sooner than 15 or 20 years from now.
No one knows for sure what will happen, but it's certainly not too early to make predictions about the future of the new plane.
Given its traditional policy of aircraft manufacturing, China will most likely create a functional analogue of foreign-made 5G planes that will cost 50% to 80% less than Russian and U.S. models. China will most likely sell the plane in Central Asia, the Middle East, Latin America and Southeast Asia, as well as to the richest African countries.
The export models of the J-20 and the planes of that series made for the Chinese Air Force will have foreign, including Russian, equipment and weapons. Moreover, in the next 20 to 30 years China will have to continue to import modern aircraft technology. Despite the strides made by China's aircraft designers in the last 20 years, China has only slightly narrowed the technological gap dividing it from the global leaders.
The views expressed in this article are the author's and do not necessarily represent those of RIA Novosti.

Re: Caça de 5a geração chinês

Enviado: Sex Jan 14, 2011 6:47 pm
por Penguin
http://sitelife.aviationweek.com/ver1.0/Content/images/store/13/2/6d32b19e-528c-4378-a249-4240e74ab8b5.Full.jpg
Lockheed's immediate pre-JAST/JSF design

http://sitelife.aviationweek.com/ver1.0/Content/images/store/7/7/8704817c-eb4f-4a83-a734-545e97616185.Full.jpg
J-20

http://www.aviationweek.com/aw/blogs/de ... d=blogDest

Re: Caça de 5a geração chinês

Enviado: Sex Jan 14, 2011 11:07 pm
por Bender
:mrgreen: Isso é que é desenvolvimento local... :roll:

Sds.

Re: Caça de 5a geração chinês

Enviado: Sex Jan 14, 2011 11:24 pm
por Wardog
^Prefere o nosso?

Re: Caça de 5a geração chinês

Enviado: Sáb Jan 15, 2011 12:14 am
por Boss
O nosso é de 8ª geração, tão stealth que nem fotos e notícias temos.

Re: Caça de 5a geração chinês

Enviado: Sáb Jan 15, 2011 11:09 am
por Penguin
Imagem

Re: Caça de 5a geração chinês

Enviado: Dom Jan 16, 2011 12:12 pm
por Moltoben
there are about 30 countries able to buil a raptorsky shape "looking like " 5G fighter and put engines into to test flights!

any country willing to design a new fighter in 2010 will not choose a badly copied 30 years old shape, but make a 6th gen fighter!


Imagem

Re: Caça de 5a geração chinês

Enviado: Dom Jan 16, 2011 12:17 pm
por Wardog
Moltoben escreveu:there are about 30 countries able to buil a raptorsky shape "looking like " 5G fighter and put engines into to test flights!

any country willing to design a new fighter in 2010 will not choose a badly copied 30 years old shape, but make a 6th gen fighter!


Imagem

Ok, but what is this plane in the picture?

Re: Caça de 5a geração chinês

Enviado: Dom Jan 16, 2011 12:37 pm
por NovaTO
O Neuron é um demonstrador de tecnologia, sendo desenvolvido em consórcio por vários países da Europa, Dassault coordenando, mas com grande participação da SAAB. É um DEMONSTRADOR, que visa manter e adquirir expertise em furtividade. Poderá gerar frutos ou não. Talvez um UCAV de ataque furtivo seria o mais viável, mas para um caça de 6ª geração, esse demonstrador está muito longe disso.

Abraços

Re: Caça de 5a geração chinês

Enviado: Dom Jan 16, 2011 2:11 pm
por marcelo l.
http://www.openthemagazine.com/article/ ... sible-bird

Bom artigo...mas, longo para colocar todo aqui

Re: Caça de 5a geração chinês

Enviado: Qua Jan 19, 2011 12:25 am
por faterra
Imagem
Chengdu J-20 fighter
1 - Esta ave já está voando?
2 - O que são estas aberturas na lateral das rodas traseiras?

Re: Caça de 5a geração chinês

Enviado: Qua Jan 19, 2011 4:26 am
por Skyway
1- Aparentemente já, apesar de eu achar muito estranhas as tubeiras dos motores.
2- São os porões do trem de pouso, com portas ridiculamente grandes e que não fecham no chão.

Eu pessoalmente não acho esse avião bonito, mas gosto é gosto. :mrgreen:

Um abraço!