The J-7E was the third-generation derivative of the Chengdu Aircraft Industrial Corporation (CAC) J-7 family. First introduced in the early 1990s, the aircraft was based on the airframe of the J-7II, but with redesigned wings and upgraded avionics. The fighter was also prompted to the international market under the designation F-7MG, and is serving with the Pakistani Air Force (PAF) under the designation F-7PG. The J-7E production began in the early 1990s and stopped in 2002. A further improved domestic variant designated J-7G was introduced in 2002.
As Chengdu’s attempt to reverse engineer the MiG-21MF Fishbed-J all-weather fighter was not entirely successful, the company went back to the J-7II (MiG-21F-13 Fishbed-C) design in the late 1980s to develop an improved variant J-7E for the PLA. The J-7E first flew in May 1990 and the flight testing had been completed by 1992. The J-7E began to serve with the PLA Air Force (PLAAF) and PLA Naval Air Force (PLANAF) in 1995. The export variant F-7MG upgraded with Western avionics was first revealed during the 1996 Zhuhai Air Show.
A significant amount of new technologies has been adopted in the J-7E/F-7MG’s development and production, including computer aided design and manufacturing (CAD/CAM), numerical control processing, laser/electromagnetic tests, composite materials, and water jet cutting. These technologies enabled the 1950s-era design to be built in the 1990s quality standards, thus improving the aircraft’s performance and capabilities.
Improvements on the J-7E mainly focused on aerodynamic performance and avionics. The original delta wing plan-form was with a new “double-delta” design similar to that of the Russian Su-15 and Swedish Saab J-35 Draken. The new wings retain the existing leading-edge sweep angle of 57° inboard but have reduced sweep angle of 42° on the outboard wing, which also has a leading-edge flap fitted. This design offered an excellent solution to the inherent low aspect ratio problem of a slender delta. The slighting larger wingspan and 8.17% more wing area also gave an increased internal fuel capacity (from 2,080kg to 4,165kg) and much enhanced manoeuvrability.
J-7E: The J-7E is the first member of the third-generation J-7 family featuring the 'double-delta' wings (source: Chinese Internet)
The aircraft’s performance was further enhanced by the introduction of an improved Liming (LMC) Wopen-13F turbojet rated at 44.1kN dry and 66.7kN with afterburning, giving a thrust-to-weight ratio of about 0.9 in clean, take-off configuration compared with 0.8 of J-7B. The sea-level climbing rate has increased from 155m/s to 195m/s; the ferry range has increased from 1,500km to 2,200km; the G limit has increased from 7g to 8g. The maximum instantaneous turn rate of the J-7E is 25.2 degree/sec, and the maximum sustained turn rate at 1,000m altitude is 16 degree/sec. According to CAC’s advertisement, compared with the J-7B, the overall aerodynamic performance of J-7E has increased by 43%, and the combat effectiveness has increased by 84%.
Avionics suite of the aircraft includes the Type 226 ranging radar, JT-1 head-up display (HUD), KW8602 radar warning receiver (RWR), Type 8430 air data computer, JD-3 tactical aircraft navigation (TACAN), KG-8605 internal radar noise jammer, and Type 941-4AC chaff/flare dispenser.
Fixed weapon includes one 30mm Type 30-1 cannon with 60 rounds fitted in lower starboard side of the fuselage. Four under-wing stores stations can carry up to 2,000kg of disposable stores (each unit rated at 500kg), typical weapons are PL-5 or PL-8 short-range AAMs, free-fall weapons such as 500, 250, 100 and 50kg bombs, and multiple rocket launcher pods each carrying twelve 55mm or seven 90mm unguided rockets. Centre fuselage station and two outboard wing stations are pumped to carry 720 litre drop tanks.
F-7MG
The F-7MG is an export fighter aircraft developed by Chengdu Aircraft Corporation (CAC) based on the J-7E. The project was jointly funded by CAC, Shenyang Liming Aero Engine Group (LMC), and China Aviation Technology Import and Export Corporation (CATIC). Liming was also responsible for the development and production of the improved WP-13F turbojet engine, while CATIC was responsible for the marketing of the aircraft.
The F-7MG was based on the J-7E airframe, but upgraded with Western avionics. The fighter was fitted with an X-band British Marconi Electronic Systems Super Sky Ranger pulse-Doppler fire-control radar. The Super Skyranger was an improved variant of the Skyranger radar used on the F-7M fighter. It has the ‘look-down/shoot-down’ capability and five working modes. The radar can track up to 8 targets simultaneously while attacking one of them.
Marconi head-up display (HUD) and fire-control computer are fitted as standard. The HOTAS (hands on throttle-and-stick) cockpit design allows the pilot to fly the aircraft without taking his eyes off the horizon and HUD, thus improving his situational awareness. If necessary, the fighter can also be integrated with a helmet-mounted display (HMS). The fighter has been added with a second 30mm Type 30-I cannon carrying 60 rounds fitted in the lower port side of the fuselage.
Other avionics include a stores management system, which helps the pilot to establish the status of stores including configuration, fusing, and weapon codes. A voice warning system, colour video recorder, elaborating cockpit lighting are also among the improvements. The colour electronic flight control system (EFCS) includes two displays, one for the altitude and the other for the heading and navigation sub-systems, such as Automatic Direction Finding (ADF), VHF Omni-directional Range (VOR), Tactical Aid to Navigation (TACAN), and Instrument Landing System (ILS), etc.
F-7MG
F-7PG
The F-7MG fighter is serving with the Pakistani Air Force (PAF) as the F-7PG. The PG variant is generally same as the MG variant but its avionic configuration has been tailored to meet the PAF requirements. As the Marconi Super Skyranger radar did not meet the PAF requirements, the F-7PG is fitted with an I-band Italian FIAR Grifo-7 pulse-Doppler fire-control radar (37km range), which was optimised to fire the U.S.-made AIM-9L all-aspect short-range AAM, making a lethal combination in air-to-air combat.
The PAK pilots first test flew the F-7MG fighter at Chengdu’s test site in 1997. Following the flight evaluations, the PAF ordered 46 F-7PGs and nine FT-7PG. The PAF was so impressed with the aircraft’s performance that it ordered an additional 11 F-7PGs subsequently.
F-7PG
J-7G
With the success of F-7MG/PG series export fighter, Chengdu quickly developed its domestic equivalent J-7G with similar design upgrades. The J-7G is equipped with an I/J-band KLJ-6E Lieying (“Falcon”) pulse-Doppler fire-control radar allegedly based on the Israeli EL/M2001. A new one-piece front windscreen replaced the original three-piece design for better cockpit visibility. Other improvements include a new Type III IFF, an indigenous zero-height, zero-speed ejection seat, and improved electronic countermeasures (ECM) suite.
The J-7G firs flew in June 2002 and entered the PLAAF service in 2004. The J-7G production is expected to last for few years before the J-10 and J-11B fighter can enter service in significant numbers. 16 examples of the J-7G fighter were delivered to the PLAAF 37th Air Division (serial number 5XX8X) based at Urumqi, Xinjiang. An additional 32 aircraft were delivered to the PLAAF 12th Division (serial number 2XX3X) in November 2006. An unarmed version designated J-7GB replaced the earlier J-7EB in the PLAAF August 1st Aerobatic Demonstration Team.
J-7G
J-7EB and J-7GB
The J-7EB is the unarmed variant of the J-7E specially designed for the PLAAF August 1st Aerobatic Desmontration Team. The aircraft has its two 23mm internal cannons removed and carries a smoke generator under the centre fuselage station. The aircraft has now been replaced by the J-7GB derived from the J-7G.
J-7s in Aerobatic Role: The J-7EB in the old (top-left) and new (top-right) August 1st Aerobatic Demonstration Team liveries, and the J-7GB (bottom) (Source: Chinese Internet)
