China's FC-31 with weapons: Illustration via Chinese media

China displayed a scale-model of its FC-31 stealth fighter jet at the Paris Airshow 2019 with different contours than that of its current prototype triggering speculation that the jet had been upgraded with new features.

“The displayed model shows noteworthy changes in design that could significantly improve its capabilities,” pro-government Global Times noted. The area behind the cockpit and the areas where the two engines are housed are now bulkier and the aerodynamic design has been optimized to further reduce wind resistance, the report noted.

These changes could mean the aircraft has been made more agile and is capable of carrying more fuel, which will give it a larger operational range; it might also carry additional electronic devices for communication or satellite links, the paper said quoting an industry expert.

The upgraded FC-31 might even feature a pair of new engines. The engine nozzles on the FC-31 model displayed in Paris are very different in structure and shape than the ones previously used suggesting more powerful engines.

Despite several years in the making, the J-31 (FC-31 is the designation for the export version), is nowhere near services entry. The first prototype/tech demonstrator flew in 2012. A second prototype with upgrades to its wings, inclusion of IRST sensor and a single piece canopy was shown at the 2014 Zhuhai airshow and its first flight happened only in December 2016.

At that time, it was believed that the design had been frozen and that the aircraft would begin the process of testing its various weapons, communication and stealth features. Speculation of project delays was rife when the jet did not put up a flying display at the 2018 Zhuhai Air show. However, with new-look mock-up at the ongoing Paris event, possibility of the project skipping timelines of prototype testing and certification cannot be discounted.