Monday marks the 10th anniversary of China's J-20 stealth fighter's maiden flight, which saw the aircraft land successfully at a test base in southwest China after an 18-minute flight.

Since then, the fourth-generation fighter jet for which China has sole intellectual property rights has had numerous tests on various prototypes.

The J-20 appeared in public for the first time in November 2016 when two jets flew in formation during the China International Aviation & Aerospace Exhibition in Zhuhai, also known as the Zhuhai Airshow.

On February 9, 2018, the People's Liberation Army Air Force (PLAAF) officially commissioned the J-20 into military service.

Analysts said at the time that compared with other fourth-generation fighters, the J-20 had clear advantages in research, development and testing. 

It took part in air warfare training with the J-16, J-10C and other fighter jets, boosting the air forces' overall combat strength, according to the PLAAF.

In May that year, the J-20 participated in its first combat training over the ocean.

Half a year later, the aircraft appeared again at the Zhuhai Airshow, flying in four-plane formation for the first time in public.

According to various sources, the fourth-generation stealth fighter was first equipped with Russian AL-31 engines, but the latest signs show that this is changing.

In a recent video released by the PLAAF for its pilot recruitment program, a J-20 was identified as the fighter jet is equipped with China's domestically developed WS-10C engine.

Computer-generated imagery of four twin-seat J-20 variations was also seen in a video released by the aircraft's developer, Aviation Industry Corporation of China.

According to the Global Times, it was the first time an official promotional source had featured such a variation.

Military analysts said the new signs show that the J-20 is heading for a higher level, enabling more complicated tasks. Domestic engines will enable mass production of the fighter jet without the limit of imported engines, they said.