Two months after the impressive new Chinese fighter, the J-20, made its first flight, it's been possible to scrutinize the photos, videos and other evidence, and form a better idea of where the Chinese are with their new "stealth fighter." While the J-20 looks like the American F-22 when viewed head on, it's overall shape, weight and engine power is closer to the American F-15C. In other words, it's about 20 meters (62 feet) long, with a wing span of 13.3 meters (42 feet). J-20 has about the same wing area as the F-15C, which is about 25 percent less than the F-22 (which is a few percent larger than the F-15 in terms of length and wingspan). Worse, for the J-20, is the fact that it's engine power is about the same as the F-15C, while the F-22 has 65 percent more power. With the afterburner turned on, the J-20 has more power than the F-15C, and nearly as much as the F-22. But because the afterburner consumes so much fuel, you can't use more than a few minutes at a time. The F-22 is still one of only three aircraft (in service) that can supercruise (go faster than the speed of sound without using the afterburner.) In addition to the F-22, the Eurofighter and the Gripen can also supercruise.
The J-20 has some stealthiness when it's coming at you head on. But from any other aspect, the J-20 will light up the radar screen. For this reason, the J-20 is seen as a developmental aircraft, not the prototype of a new model headed for mass production. As such, it is only the fifth stealth fighter to fly, the others being the U.S. F-22 and F-35, plus the Russian T-50 and I.42. The older U.S. F-117 was actually a light bomber, and the B-2 was obviously a heavy bomber. Based on recent Chinese warplane development projects (J-11 in particular), the J-20 has a long development road ahead of it, and will likely change size and shape before it reaches the production design.
While the shape of the J-20 confers a degree of stealthiness (invisibility to radar), even more electronic invisibility comes from special materials covering the aircraft. It's not known how far along the Chinese are in creating, or stealing, these materials. Same with engines. The current J-20 engines are sufficient for early flight tests, but not capable of providing the supercruise, something that would be essential for the J-20. That's because China would most likely use the aircraft singly, or in small groups, to seek out and attack American carriers. As for F-22 class engines, that is being worked on. Two years ago, China announced it was developing the WS-15 engine, a more powerful beast well suited for the J-20. No date was given as to when the WS-15 would be available for use, or whether it would have the same vectoring (ability to move the hot jet exhaust in different directions in order to make the fighter more maneuverable) the F-22 uses.
For the J-20 to be a superior fighter, it would need electronics (including radars and defense systems) on a par with the F-35 and F-22. So far, the Chinese have not caught up with stuff used by current American fighters. But the gap is being closed, faster than it was during the Cold War and the Russians were creating, or stealing, their way to military tech equivalence with the West.
Work on the J-20 began in the late 1990s, and the Chinese knew that it could be 25 years or more before they had a competitive stealth fighter-bomber. The J-20 is being tested at an airfield near the Chengdu Aircraft Company (CAC), which builds the J-10 and JF-17. Located in central China, CAC was known to be working on the J-20.
The twin engine J-20 appears to be about the same weight as the 30 ton F-15C. The F-35A is a 31 ton, single engine fighter while the twin-engine F-22 is slightly larger at 38 tons. The I.42 was a 42 ton aircraft, and the T-50 weighed in at 37 tons.
China is also developing other support technologies, like the AESA radar, highly efficient cockpit, stealth and software to tie everything together. Developing, or even copying, this tech is not easy. But the Chinese already know that, having decades of experience adapting stolen technology to their needs. Thus it appears that China is planning on having the J-20, in some form, ready for service by the end of the decade. The key factor is their ability to develop or steal the needed technology by then. The J-20 appears to be a fighter-bomber, as this kind of aircraft would be most useful dealing with the U.S. Navy and key targets in Taiwan or Japan, In any event, the J-20 is an attempt to develop some kind of 5th generation aircraft, complete with stealth.
The only other competitor in this area is Russia, where fifth generation fighter developments were halted when the Soviet Union disintegrated in 1991. Actually, all development work on new fighters, by everyone, slowed down in the 1990s. But work on the F-22, F-35, Eurofighter and Rafale continued, and those aircraft became, in roughly that order, the most advanced fighter aircraft available today. MiG resumed work on the I.42 in the 1990s, but had to stop after a few years because of a lack of money. Sukhoi has never stopped working on its T-50, funded by much higher sales of its Su-27/30 fighters. This fifth generation may come to be called the "last generation," after they are replaced by the second generation of pilotless combat aircraft (counting armed Predators and the like as the first).