J-7 Fighter Aircraft

Last updated: 3 August 2008

J-7III (J-7C)

As the J-7I and J-7II day interceptor fighters could not meet PLAAF’s requirements, Chengdu began to develop an improved all-weather variant in the early 1970s. The project was initially proposed in 1972, but it did not enter full-scaled development until the late 1970s. The development and production responsibilities were shared between Chengdu Aircraft Factory (now CAC) and Guizhou Aircraft Factory (also known as Base 011, now Guizhou Aviation Industries Group Co, GAIGC). Chengdu was responsible for the aircraft’s fuselage as well as flight testing. Guizhou was responsible for the aircraft’s wings and the landing gear. The aircraft received official designation J-7III (later renamed J-7C).

The J-7III variant was to be based on the Soviet MiG-21MF (NATO codename: Fishbed-J), which was the all-weather, multirole fighter version of the MiG-21 family. China obtained an example of MiG-21MF from Egypt in February 1979. The aircraft was then handed to Chengdu for reverse-engineering. The development began in May 1979 and was completed by May 1980. J-7III was the first Chinese-made aircraft to have used computer aided design (CAD) and system engineering management in its development. Static testing of the airframe was completed in April 1984, and the aircraft made its first flight on 26 April 1984.

	The J-7C in the camouflage paint scheme (Chinese Internet)

Despite sharing the same designation with previous J-7 models, the J-7III was largely a new design, with 80% of its parts being newly developed. The aircraft is generally similar to MiG-21MF in aerodynamic design, though its avionics, armaments, and powerplant were all indigenous designs.

J-7III was the first Chinese-made fighter to be fitted sophisticated avionics suite for all-weather operations. The enlarged nose inlet cone accommodated a JL-7 multi-purpose pulse Doppler (PD) fire-control radar, which had a maximum detecting range of 30km against airborne targets. Based on integrated circuit technology, the JL-7 radar could work in air-to-air or air-to-ground mode. In air-to-air mode its functions included air target search, manual target acquisition, identification of friend or foe, target tracking using optical gun sight or head-up display (HUD), tail attack. In air-to-ground mode the radar could perform rangefinding and ground attack using optical sight.

The aircraft was originally fitted with a SM-8 (HK-03D) optical sight, but this was replaced by a HK-13A head-up display (HUD). Other avionics included KJ-11 autopilot, ADS-1 air data computer, WL-7 radio compass, 264A radio altimeter, XS-6A beacon marker receiver, Type 481 data transmission/navigation system, Type 506 HF radio, Type 605A IFF, Type 930-II radar warning receiver (RWR), and GT-1 and chaff/flare dispenser.

The aircraft was powered by an improved WP-13 turbojet developed by Guizhou Liyang Aero Engine Company. The engine was rated at 4,100kg dry and 6,600kg with afterburning. Like MiG-21MF, J-7III had an enlarged dorsal spine to accommodate additional fuel. As a result, the aircraft had its cockpit canopy redesigned with a fixed three-piece windscreen and a (right) side-hinged canopy. The enlarged dorsal spine further reduced the aircraft’s already poor cockpit visibility. Therefore the pilot had to rely completely on a single canopy mirror for rear vision. The aircraft's escape system had a HTY-4 rocket ejection seat.

J-7III carried four PL-2 or PL-5 IR-homing, short-range air-to-air missiles under the wing stations. The centreline fuselage station is pumped to carry a 480 litre or 760 litre drop tank. Alternatively it could be used to carry integrated bomb pylon, navigation pod, targeting pod, reconnaissance pod, or EW/ECM pod. For air-to-ground attack the aircraft carried 57mm, 90mm or 130mm rocket launcher pods under the wing stations. Fixed weapon included a Type 23-III 23mm twin-barrel cannon with 200 rounds.

Despite PLAAF’s high hope in the J-7III fighter, the aircraft later proved trouble prone. The JL-7 fire-control radar was unreliable and lacked features such as ‘beyond-visual-range’ (BVR) combat and ‘look-down, shoot-down’ which were commonly found on Western and Russian fighters introduced in the same age. The modification in the airframe design also increased the aircraft’s external profile and overall weight considerably, resulting in degraded manoeuvrability. The fighter only saw limited service (20~30 examples) with PLAAF under the designation J-7C. Painted in the special camouflage colour scheme, these J-7Cs were used as dedicated night fighters in PLAAF 15th Air Division based at Zhangjiakou, Hebei Province.

	The J-7D variant in service with the PLAAF (Chinese Internet)

J-7D

In response to J-7C’s weaknesses, Chengdu and Guizhou introduced the improved J-7D (originally named J-7IIIA or J-7IV) in the early 1990s. The improvements focused on the avionics, including the JL-7A fire-control radar, HK-13A HUD, JD-3II tactical aircraft navigation (TACAN) system, Type 563B inertial navigation system (INS), KJ-8602 radar warning receiver, and TKR-122 VHF radio. The powerplant was replaced by an improved WP-13F1 turbojet with increased thrust. The J-7D fighter was capable of firing the more advanced PL-7 and PL-8 short-range AAM, but still lacked the BVR combat capability.

Development of J-7D began in 1988, and the aircraft first flew on 20 August 1991. The production was approved in November 1994 and the fighter achieved initial operation capability with PLAAF in 1995. By then the PLAAF had already decided to allocate its resources to more capable fighters such as Su-27/30 and J-8B. As a result only 20~30 examples of the J-7D were built before the production finally stopped in 1999.

Unlike other members of the J-7 family, the J-7C and J-7D do not have export versions.