China's J-31 Stealth Fighter: Then and Now
J-31's Debut
The J-31 "31001" technology demonstrator flies past in a public demonstration at the Zhuhai 2014 Airshow. In addition to generating export interest, Shenyang Aircraft Corporation is looking to get J-31 business from the PLAAF.
Hunter Chen
Much has been made of China’s J-31 stealth fighter making an appearance at the 2014 Zhuhai Airshow. (Too much in fact; for example
Foreign Policy magazine tried to tie the news to Obama’s visit this week, despite the fact that the airshow has been going on since 1996 and the plane flying since 2012.) But what can we learn from its appearance?
J-31 Lands
The J-31 "31001" makes another approach at Zhuhai. The J-31 is still a tech demonstrator at this point, and lacks extras like electro-optical and missile launch warning sensors, as well as likely using a preexisting radar (J-10) at this point.
Flyer via Weibo
Made by the Shenyang Aircraft Corporation (SAC), it is highly likely that the J-31 will be China's version of the Joint Strike Fighter; its development is expected to spiral into both PLAAF and PLANAF variants. However, the J-31’s primary mission at Zhuhai has been to hunt for export customers. Beyond Chinese sales, likely customers for the J-31 include nations that have operated earlier generation Chinese export fighters like the F-7 and JF-17 (such as Pakistan and Egypt), as well as those looking for less expensive or non-U.S. alternatives.
J-31
The J-31 differs from the F-35 in that it has two engines, which in turn reduces its area ruling, making for more efficient supersonic flight, including future supercruise once the J-31 obtains more powerful engines.
Hunter Chen
Currently, "31001" is a technology demonstrator for SAC's stealth fighter technology. Hence it uses preexisting systems, like the Russian RD-93 engines found on the FC-1 fighter, as well as having an older two piece canopy over the cockpit. "31001" was stated at the Zhuhai 2012 airshow to have a combat weight of 17.6 tons; like the transition from the X-35 to the F-35, production variants of the J-31 are likely to be heavier than the demonstrator.
FC-31
This up to date scale model of the FC-31 (the J-31's export designation) at Zhuhai 2014 shows several important upgrades from "31001", including the installation of a Electro Optical Targeting Sensor (EOTS) pod under the nose (shiny gold fairing).
Blitzo at Sinodefense Forum
Stealthines
The updated FC-31 design has several radar cross section reduction measures, such as clipped wing edges, and revised vertical stabilizers, to reduce reflected radar waves.
Andreas Rupprecht via China Defense Forum
While "31001" flew crowd pleasing maneuvers at Zhuhai, a new and updated scale model of the J-31, or FC-31 in its export designation, on display shows changes that would come to any likely final plane. The new model has redesigned wings, clipped at the corners to enhance stealth, and all new vertical stabilizers, which have been enhanced for stealth. The new model also has an Infrared Search and Track sensor installed on the underside of its nose, to enable the J-31 to track the heat signatures of enemy aircraft. It also has redesigned, stealth optimized engine nozzles, which suggest that a Chinese 10- to 11-ton thrust engine will ultimately replace the Russian RD-93. Notably, such future engines could allow the J-31 to supercruise, a feature that the F-35 does not have.
New Engines
The stealthy new engine nozzles on the FC-31 model indicate that SAC looks to replace the current RD-93 turbofans. The yet unnamed turbofan engines will each generate about 10-11 tons of afterburning thrust, which could enable the J-31 to supercruise.
mil.ifeng.com
Next Gen Display
This flight simulator/cockpit avionics display shows state of the art pilot/cockpit interface technology, including a holographic Heads Up Display (HUD), a built in helmet wide display, and multi-functional display screens (not shown) that would show and fuse sensor data, managed communications, as well as firing and controlling weapons.
china.com
The J-31 is clearly intended to be a true “fifth-generation” fighter, not only in stealth but also in sensor fusion and flight avionics. To its advantage, the J-31 does not have the difficult challenge of producing a design that allows both traditional flight and a STVOL variant like the F-35B. However, the great challenges in producing a multi-role fifth-generation fighter and high-performance engines means that SAC has its work cut out if the J-31 is going to enter service in 2022, a decade after its first flight.
China's J-31 Stealth Fighter: Then and Now | Popular Science