According to the test pilot of PLAAF, the Chengdu J-20 fighter is likely to integrate two-dimensional thrust vectoring engines for improved manoeuvrability.
The Chengdu J-20 is a single-seat, twinjet, all-weather, stealth, fifth-generation fighter aircraft developed by China’s Chengdu Aerospace Corporation for the People’s Liberation Army Air Force (PLAAF).
The J-20 made its maiden flight on 11 January 2011 and the aircraft entered service in March 2017.
The aircraft has continued to integrate new features and upgrades which have significantly improved the performance of successive batches of fighters over the past four years.
The beginning of serial production of a new variant of the aircraft, the J-20B, from 2020, is expected to see a number of new improvements, including a stealthier and more durable high composite airframe.
The pilot of the J-20’s first flight, Li Gang, indicated that the fighter is likely to integrate two-dimensional thrust-vectoring engines for improved manoeuvrability – meaning these could become a standard feature for the J-20B.
Thrust vectoring engines were pioneered by Russia in the 1990s, and are currently used to improve maneuverability on five aircraft classes including Russia’s Su-30, Su-35, and Su-57, America’s F-22, and China’s J-10C.
Of these, the older F-22 and Su-30 use two-dimensional thrust-vectoring engines while the three newer aircraft which all entered service since 2014 have three-dimensional thrust vectoring. China is thought to have benefitted from technology transfers from Russia’s defence sector to acquire three-dimensional thrust vectoring engine technologies – which are speculated to have been sold along with the 24 Su-35 jets the country purchased.
Thrust vectoring engines are highly prized for the overwhelming advantage they can provide fighters with in short range engagements, although they add considerably to the weight and cost of the aircraft.
It may be that three-dimensional thrust-vectoring engines are seen as unnecessary for an aircraft such as the J-20 which is optimised for long range combat and relies more heavily on stealth than manoeuvrability to remain survivable – leading to the decision to integrate engines with two-dimensional thrust vectoring.
Li Gang noted that in the future more capable thrust-vectoring engines could be integrated onto the J-20 with nozzles that can move both vertically and horizontally like those on the Su-35 – but unlike those on the American F-22 which can move only vertically.
There has been some speculation that the J-20 has already begun to integrate thrust-vectoring engines at least for testing purposes, with the fighter’s chief designer Yang Wei stating in 2018 when asked when the J-20 would integrate such engines “You asked about when, but how do you know it hasn’t?”
The J-20 is currently the only stealth fighter developed outside the United States that is widely operated, with only Russia having otherwise developed a fifth-generation fighter with the Su-57 although only a single one of these aircraft is in service.