Something old, something new: the very practical rules of Chinese aircraft development
Year-end revelations of two new Chinese combat aircraft designs, the Chengdu J-36 and the Shenyang J-XX, should have put an end to the idea that China’s aerospace and defense industry just copies the West.
Yet sometimes China does produce copies, for good practical reasons. At other times it just does its best with the technology it happens to have available.
Here are some principles that Chinese military aeronautics development follows.
Copy if possible and necessary. The Xi’an KJ-600 configuration copies the Northrop Grumman E-2 Hawkeye’s, down to details. As on the E-2, one of the inboard fins of the four-fin tail has a moving rudder and the other doesn’t. That works on the Hawkeye, so why do it any other way? There’s a reason that the Hawkeye is still in production after 66 years.
KJ-600. Original image source unknown.
Good enough. The Xi’an H-6 bomber is the Soviet Tu-16, 12 days younger than the B-52. But at the age of 55, the design got a complete makeover from the Chinese industry: a new forward fuselage housing a three-member crew, all with ejection seats and glass displays, and a multi-mode radar. 1970s Russian engines replaced the 1950s originals.
The H-6K update and later versions provide the Chinese air force and naval aviation force with a heavy weapons platform with some features that even the forthcoming B-52J (a B-52 update with new engines) cannot match: the Chinese bomber has six wing pylons and an ability to carry an outsize store on its centerline.
Innovate to meet urgent needs. Those stores include not only an air-launched boost-glide weapon but the AVIC WZ-8, one of a group of very innovative Chinese military drones that represent a much more creative culture than what we see in Western aerospace.
WZ-8. Image: Wikipedia.
The WZ-8 is an air-launched, runway-recoverable drone with a blended-delta shape and rocket propulsion. It has (by US intelligence estimates) a speed of Mach 3 at 30,000 metres altitude and a range around 500 nautical miles (900km) including a long gliding descent.
In most respects, it could have been designed and built in the 1950s. But a remarkable feature of the WZ-8, visible on the website of a company specialising in additive manufacturing, is that the entire center-section box, the structural heart of the aircraft, is 3D printed in titanium.
The WZ-8 is the definition of a point design—an inflexible one intended for a single purpose. China regards the ability to attack US aircraft carriers as a strategic goal. And it’s well known that the US Navy relies on its carriers’ ability to move fast and far in the time between when they’re detected and when an attack on them arrives. Jamming and decoys help. The WZ-8’s job is a last-minute reconnaissance sortie to locate the carrier.
Borrowing technology that the West has ignored. The Guizhou WZ-7 Soaring Dragon drone, in service in small numbers, resembles a Northrop Grumman Global Hawk in size and body shape. But it has a four-surface joined wing.
Advantages claimed for the joined wing include combining a skinny wing shape (high aspect ratio, to the aerodynamicists), thinness and sweep. The result is an unusual combination of high speed and low drag.
The joined wing was invented in the US and has been studied by NASA several times, but the space-fixated agency never found budget to demonstrate it in flight. The Chinese designers would have found plenty of open-source data to work from.
WZ-7. Image: Wikipedia.
But another drone, Shenyang’s WZ-9 Divine Eagle, has no parallel. It is a high-altitude carrier for two large-aperture radar arrays. Its status is uncertain. It was first seen in 2015 and reappeared on video in late December. The two radar antennas occupy separate fuselages, connected at their front and rear extremities by a wing and canard, with a single engine above the wing. With no crew and high-aspect-ratio wings, the drone can fly higher than a big-cabin crewed platform and has a longer radar horizon.
The WZ-9’s unique shape indicates something about China’s electronics technology. The designers must believe that their radars are so efficient that the cost in weight of carrying two separate units, each with its own power supply, is acceptable. The concept also shows that China can rely on using datalinks alone to operate a complex radar system.
The WZ-9 and WZ-8 typify another trend in China’s technology: firing weapons from one platform (a ship, submarine, aircraft or ground vehicle) by using targeting data from another source. Western experts already believe that China’s growing, diverse fleet of airborne radar systems can be used for direct weapon guidance. The WZ-9 allows weapon-quality guidance to be extended farther without endangering a large crew on an aircraft that cannot defend itself.
Viewed as a group, alongside new combat aircraft like the J-36 and J-XX (J-XDS, according to some sources), these programs also illustrate another, hugely important feature of Chinese aerospace development: the sheer number of new and unique projects.
An engineer who started at Chinese fighter specialist Chengdu Aircraft in the late 1990s could have successively joined new development programs for four combat-aircraft types—the JF-17, J-10, J-20 and J-36. That engineer could also have worked on major upgrades and engine changes for the first three of those. All have entered service or are on track to do so. Working at rival Shenyang Aircraft would provide a similar experience level, with Xi’an Aircraft not far behind.
That engineer’s US counterpart might have worked on one new program from inception to service entry—if he or she had chosen the right company to start with.
It is that growing experience gap, rather than individual systems, that should worry us more than it does.