China is building a new carrier-based fighter jet to replace its J-15 fighters. The J-15 was based on a prototype of the fourth-generation Russian Sukhoi Su-33 twin-engine air superiority fighter, a design that is more than 30 years old. It was developed by Shenyang Aircraft Corporation, a unit of state-owned Aviation Industry Corporation of China.

With a maximum take-off weight of 33 tonnes, the aircraft is the heaviest active carrier-based fighter jet in the world, used on China’s first aircraft carrier, the Liaoning.

China’s FC-31 is a newer generation stealth fighter that made its first flight in 2012 and is smaller and lighter than the J-15.