The J-10B is a modified variant of the J-10 multirole fighter aircraft, with modifications in airframe and avionics. Chengdu Aircraft Corporation (CAC) of AVIC began to develop a follow-on variant of its J-10 fighter around 2004/05. A J-10B prototype reportedly made its maiden flight in December 2008. Photos of the aircraft began to emerge on the Chinese Internet in March 2009. Once commissioned, the J-10B is likely going to become the standard for later J-10 productions.
Rampless Inlet
The J-10B features a chin-mounted diffuser supersonic inlet (DSI) air inlet. The traditional rectangle-shape air inlet on the J-10 requires a large moveable inlet ramp to generate a rearward leaning oblique shock wave to aid the inlet compression process. The ramp sits at an acute angle to deflect the intake air stream from the longitudinal direction. The air inlets comprises many moving parts, which increases the aircraft’s weight and radar reflections.
The newly designed rampless inlet, first tested on the FC-1/JF-17 fighter design by Chengdu, employs a one-piece bump at the top of the inlet replacing the movable ramp. This eliminates all moving parts on the inlet, lightening the overall weight and reducing the aircraft’s radar signature.
Electro-Optic Targeting System
The J-10B has been added with an electronic-optic targeting system (EOTS) commonly found on all fourth-generation Russian fighter aircraft such as Su-27 and MiG-29. Placed forward of the cockpit canopy to the right, the system comprises an infrared search and track (IRST) sensor and a laser rangefinder, which can detect enemy targets passively without requiring to turn on the fire-control radar, thus reducing the chance of the aircraft being detected. The EOTS of the J-10B is likely based on a Russian design.
Tailfin ECM Pod
The upper edge of J-10B’s tailfin is curved, in contrast to the straight-edged tailfin of the J-10. A large fairing is added to the tip of the tailfin to accommodate electronic warfare and countermeasures (EW/ECM) equipment.
ECM Antenna Array
The J-10B has four black antenna arrays attached externally to the fuselage, a larger one on either side of the cockpit and a smaller one on either side of the rear fuselage near the engine nozzle. The specific purpose of these antennas is unknown but they are thought to be for electronic countermeasures purpose.
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