https://nationalinterest.org/blog/reboot/china%E2%80%99s-j-20-stealth-fighter-getting-major-boost-thanks-russia-181006
China’s J-20 Stealth Fighter is Getting a Major Boost - Thanks to Russia
In yet another example of Sino-Russian military cooperation, Chinese J-20s will be carried aloft on the backs of Russian engines.
Here's What You Need to Remember: Ultimately the newest variant of the Chinese-built J-20, the J-20B, is intended to be equipped with powerful Chinese-designed WS-15 engines that would offer increased performance, likely better fuel efficiency, and a higher-altitude flight envelope. But because the production of the newer engine is lagging behind schedule, China has opted for a foreign design made in Russia.
One of the J-20’s more prominent features are canards, small wing-like control surfaces near the cockpit. Although canards are not necessarily incompatible with stealthy designs, they present radar operators with another surface that can reflect radar away from an airframe and amplify an aircraft’s radar signature. But the potential problems don’t end there—engines are another area that hinders the J-20.
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