Key Points
CAD images that have appeared on Chinese websites suggest a strike version of Shenyang's J-31 stealth fighter
The CAD images cannot be verified but would make sense given the PLAAF's lack of interest in the existing J-31 programme
Computer-aided design (CAD) images that have appeared on the Chinese internet indicate that the Shenyang Aircraft Corporation (SAC) may be considering a larger "strike" version of its J-31 fighter.
It is not possible to confirm whether these CAD images are from a corporate source, such as SAC's 601 Design Institute, or perhaps the work of a student from the associated Shenyang University of Aeronautics and Astronautics, which was involved in designing a flying scale model of the J-31 first seen in 2010.
However, it is plausible that SAC would be working on additional variants of the J-31, which is an industry rather than military-funded programme.
The lack of People's Liberation Army Air Force (PLAAF) support for the existing J-31 may have prompted SAC to develop a new version that may prove more attractive.
The lengthened J-31 concept is reminiscent of the US Air Force's interest in a stealth fighter-bomber version of the Lockheed Martin F-22, sometimes called the FB-22, which was abandoned in favour of a new long-range bomber.
The CAD images show a triplane-configured fighter with front canards and rear horizontal stabilisers. The chined nose and the vertical stabilisers are similar to the J-31 fighter that first flew on 31 October 2012. The design also features clear planform co-ordination among the lifting surfaces to aid low observability.
The wing is much larger than the J-31 and increases fuel capacity for a greater strike radius, but the fuselage does not appear to be much wider. An internal weapon bay is not pictured but one image shows it armed with a single YJ-12 supersonic anti-ship missile on the centreline.
A chart that also appeared online shows the new design in comparison to the SAC J-15 carrier fighter, suggesting a possible future role on China's current and future aircraft carriers.
The chart shows that in terms of length, height, and wingspan, the new design is only slightly larger than the J-15, and as such may be compatible with Liaoning, China's Kuznetsov-class aircraft carrier, and a second indigenously designed carrier expected to be similar in size and configuration.
This lengthened and heavier version of the J-31 would require a more powerful engine than the Klimov RD-93 fitted to the J-31 to be employed from a short take-off but arrested recovery carrier such as Liaoning.
Russia's Klimov bureau has developed the 20,000 lb-thrust RD-33MK, while unconfirmed Chinese sources indicate that a slightly more powerful version of the WS-13 turbofan is also under development. The WS-13 has been WS-13 testing on a Chengdu FC-1 fighter since about 2010.