May.25 (China Defense Mashup Reporting by Johnathan Weng) -- Based on the J-7II, the JJ-7 is a supersonic fighter‑trainer and primarily used for the training programs of the J-7 and J-7 II, and the J-7M. Improvements and additions of JJ-7 consist of an aft cockpit, a new forward view periscope, twin ventral fins, fuel tanks inside the top fuselage, modified intake, improvements in the ejection escape system, air conditioning, a new fuel system, red cockpit lighting, an interphone system, and a failure simulation system. The conceptual design was started in 1979, and was completed in 1983. Trial production also began that same year. Static testing of airframe carried out and finished in May 1985. Fight testing began in 1985 in Guizhou . In the first flight tests, the JJ-7’s cockpit was too high due to problems in the air conditioning system. This problem, however, was eventually solved. In February 1988, the design of the JJ-7 was certified. The JJ-7 gave the Chinese a Mach 2 trainer and was made available for export.
