China Claims To Be Developing Two-Seater J-20 Stealth Jet, But Evidence Remains Off The Radar

The Mighty Dragon With Two Heads?

The first stealth fighter developed and produced outside of the United States, the J-20 is a beefy twin-engine fighter believed to exhibit high speed, good range and payload, and decent forward-aspect stealth to be leveraged in air superiority and limited precision-surface strike roles.

On the downside, its current stop-gap engines fall short of producing the desired thrust, it is thought to be less maneuverable than peers, and its side and rear aspects are though to be significantly more radar reflective.

Chinese industry is particularly working on improvements to the J-20’s propulsion system, including developing higher-thrust domestic WS-10C and WS-15 turbofan engines, possible vector-thrust controls to enhance maneuverability, and serrated exhaust nozzles designed to reduce radar cross-section when scanned from the rear.

The claim that the Chengdu Aerial Design Institute has been “working” on an innovative two-seat J-20 for several years (with an unveiling to come “soon”) originated on a social media post by a small defense company and then was picked up by major periodicals.

But even the source rumors remains vague as to how far the development effort has advanced. For example, there’s no claim or photographic evidence that a prototype exists or is under construction.

An image cited as “proof” (see below) of the two-seat J-20 involves sketches of an ejection system posted by a Chinese defense company claimed to show a seating configuration resembling the side-by-side seating on the duck-billed Russian Su-34 Fullback bomber, rather than the tandem arrangement found on most two-seat fighters.

Side-by-side seating has the benefit of improved cooperation between the crew, but widening the fuselage would entail even more extensive alterations to the airframe than stretching the cockpit area rearward.

However, as the sketches cited as proof are from the side aspect, it’s hardly clear that they show the claimed two-seat arrangement. Furthermore, the same image was earlier attributed to show a rival FC-31 stealth fighter instead!

Andreas Rupprecht, author of numerous books on Chinese military aviation, messaged me that “… a [J-20] twin seater is in my opinion highly likely….but in my opinion never ever as a side-by-side type like the Su-34.”

A social media account run by Australia’s Air University described the claims as “sensationalist” and unsupported by evidence.

Two-seat jet fighters most commonly are used as combat-capable advanced trainers like the F-15D or Rafale-B, and/or as fighter bombers like the F-15E Strike Eagle, in which case the back seat Weapon Systems Officer (WSO) more efficiently operates sensors and precision-guided weapons, freeing the pilot to focus on flying.

Indeed, hawkish Chinese state-owned periodical Global Times reports that a two-seat J-20 may see use as a high-speed fighter-bomber, comparing it to the abandoned concept for a regional bomber variant of the F-22 Raptor called the FB-22. But the Times also mentions a potential role as an electronic warfare (EW) aircraft presumably akin to the U.S. Navy’s EA-18G Growler jets.

An anonymous insider cited by Minnie Chan of the South China Morning Post claims to the contrary that the two-seat J-20 would carry only a few air-to-air missiles internally for self-defense. Instead, the back-seater would use advanced sensors and communication systems to turn the airplane into a stealthy “early warning” plane with the ability to provide command and control support to drones, manned aircraft and even ground-based missile launchers.

Stealthy Coastal Artillery Spotter?

Serving as a mini-AWACS may sound like a strange role for a high-performance jet fighter and Rupprecht wrote to me that the Post’s military articles are regarded as unreliable by many PLA military watchers.

However, the U.S. Air Force has long maintained that its F-35 stealth fighters could serve as a force multipliers by networking their powerful sensors with friendly forces a safer distance away. And a fast, stealthy scout could also fill in a gap in China’s naval warfare strategy.

China has built a formidable arsenal of anti-ship ballistic and cruise missiles on trucks, ships and aircraft that can target ships from hundreds of miles away. But those weapons only work if the launch platform receives up-to-date target data on the ship’s location and bearing, which usually will require a “spotter” with sensors much closer to the vessel. Forming a kill chain between the spotter and the shooter is argued to be the Achille’s heel of China’s long-range ship-killing weapons.

In the suggested role, a J-20 could offer a fast-response link in the kill chain that would be harder to detect and far less vulnerable to surface-to-air missiles and fighters than a traditional maritime patrol plane.

One possible concept of operations would be to dispatch a two-seat J-20 to follow up on initial reports of enemy warships, provide a precise firing solution and perhaps even stick around to provide mid-course updates to the missile or verify whether a missile volley hit or not.

In fact, China has reportedly developed its DR-8 supersonic stealth drone to perform that mission. That shows interest in that concept, but doesn’t explain why China would also pursue a pricier manned stealth jet to that job as well. However, a two-seat J-20 drone might serve as a relatively survivable drone-control platform, a concept known as Manned-Unmanned Teaming.

Manufacturing a two-seat J-20 would effectively entail a radically altered airframe, a task further complicated by the need to maintain a low radar cross-section. That’s surely a big factor as to why the U.S. Air Force never made two-seat variants of its F-22 an F-35 stealth fighter, unlike the two-seaters models of its F-15D, F-16D, and FA-18F non-stealth jets.

Furthermore, while the J-20 is believed to have greater range than the average tactical fighter, it still would have vastly less loiter time over the Pacific than a traditional maritime patrol aircraft.

Lastly, it’s worth noting that the presence of a J-20 scout might still be detectible by the low-band radars on U.S. Navy ships and E-2D Hawkeye early-warning aircraft, even if those radars aren’t precise enough to provide targeting data for missiles. In that event, a J-20 scout might still have to avoid being intercepted at close range by a carrier taskforce’s combat air patrol (CAP), which may include Super Hornet fighters equipped with longish-range Infrared-Search and Track systems (IRSTs).

Regardless, the reports in Chinese media at least suggest a degree of interest in and a rationale for China to develop the world’s first two-seater stealth fighter. If a serious effort is genuinely being undertaken to build a two-seat J-20, firmer evidence will likely emerge in time.