Analysis The death-tech beat has spoken of little else but China's new "stealth fighter" for some weeks now – and yesterday, funnily enough just as the US Defense Secretary was visiting Beijing, the J-20 (or whatever it may turn out to be officially called) finally took to the air.
The People's Republic is making no real effort to keep the plane secret – interested bloggers and photographers have been able to watch the plane in ground trials unhindered from the fence line at the Chengdu test site for weeks. Needless to say, vids of yesterday's first flight are widely available:
As will be obvious from the clips and many online pictures of the new plane, the J-20 (or J-whatever, as the craft's official number has not been announced) has been designed to be "low observable" – that is, difficult to see on radar, at least from certain angles.
Such a shape, combined with many other rather more difficult technologies (radar-absorbent coatings, heat dump into the fuel tanks to lessen infrared signature, complex frequency-hopping invisible radars and communications, etc, etc), offers so-called "stealth" capability. This doesn't mean that a plane is totally invisible to the enemy, just that – hopefully – it can detect and strike airborne opponents while they are still unable to get a lock on it. Alternatively, when trying to penetrate an enemy's groundbased air-defence system, a stealth plane may be able to avoid detection for part or all of its mission by flying carefully planned routes and/or cooperating with supporting electronic-warfare jammer aircraft.
There's no particular indication that China has any of the necessary supplementary technologies to create a true stealth capability. Furthermore, the J-20's shape indicates that its low-observability on radar would probably be much more limited in angle than is the case with operational stealth planes such as the US F-22 Raptor and B-2 Spirit (there's very little effort to stealth up the exhausts compared to the US designs, for instance, and the intakes and control surfaces look likely to be a lot more visible from a lot more places on the sphere of possible viewpoints around the aircraft).
Then, the J-20 is plainly large and cumbersome, and appears to lack thrust vectoring. One possible theorised effect of stealth design on air combat is that opposing stealth fighters – unable to lock each other up for long-range missile duels – would find themselves tackling one another in close-in dogfights using such tools as helmet-mounted sights and agile short-ranged missiles able to attack targets well off the launching fighter's line of flight. The cumbersome J-20 would probably suffer a gruesome fate in close with the highly manoeuvrable Raptor, or even the more affordable F-35 Lightning II.
Indeed, as China almost certainly can't yet build a Raptor-style stealthy targeting radar (and thus J-20 style jets would be unable to use long-range missiles while remaining unseen) the J-20 would probably be defeated even by ordinary Western fighters such as the F-15, Rafale and Eurofighter. If it lit up its radar to shoot at them from afar, they would instantly detect it and win the fight with long-ranging missiles such as the forthcoming Meteor. If the J-20 remained silent and stealthy in a meeting engagement it would encounter enemy fighters at short range, where their manoeuvrability and dogfighting weapons would defeat it easily.
If the J-20 has a military purpose (rather than merely being a demonstration/propaganda/industrial-subsidy project as is probably the reality) it would be to act more as a bomber than a fighter – to try to slip undetected past opposing air defences and strike at key targets: enemy bases, aircraft carriers, patrolling AWACS planes and such like. But this is highly unrealistic in today's Pacific; the whole Far East is a chain of US allies from Japan down to Australia, thickly sown with powerful American and allied air forces able to sweep the skies with radar and infrared-search-and-track (IRST) scanners, both ground and airborne. The seas are full of dangerous warships – US supercarriers each equivalent to a mobile Taiwan, Aegis air-defence vessels able to sweep hundreds of miles of sky, warships and submarines able to launch thousands of cruise missiles at targets far inland.