In early 2009 images of the first prototype of the advanced J-10B variant emerged on a number of Chinese websites.
The design has a number of prominent changes which will improve performance and capabilities.
The radome geometry has been altered with a new tilted bulkhead which will reduce radar bay RCS. Aft of the radome is mounted a new electro-optical sensor turret, most likely an Infra-Red Search / Track (IRST) set. The dark colour could be a painted dummy optical dome, or a Germanium longwave dome.
The most important design change is the completely revised higher massflow inlet design. The new inlet combines two design features observed in earlier US designs, a general arrangement similar to the F-8U3 Crusader III prototype, and a diverterless inlet bulge design similar to the F-16 demonstrator used to prove the inlet design for the X-35 JSF demonstrators. The inlet to fuselage join will significantly reduce the radar signature of the forward fuselage in the upper bands.
Other interesting changes include an extended antenna fairing on the vertical fin, and large inboard pylons - or instrumentation pods - with what appear to be dielectric radomes over the front and aft of the pylon. The prototype carries inert PL-8 Python 3 rounds.
To date no performance figures have been disclosed. What is clear is that this design has been engineered to be fitted with a more powerful engine and radar than the J-10A.