The Chinese Air Force has come a long way in the last two decades. Currently the Chinese have 2,100 combat aircraft and most (63 percent) of them are modern designs. A decade ago, it was just the opposite, with most Chinese combat aircraft being older Russian models, like the J-7 (a licensed version of the MiG-21). China had upgraded these older Russian designs but they were still much less capable than Chinese versions of the more modern Russian Su-27/30 class aircraft.
China has long kept older warplanes in service, even though many had become obsolete. In 2010 the Chinese fighter force consisted of nearly 500 modern aircraft (J-10s, J-11s, Su-30s), 500 J-7, 300 J-6 (equivalent to the MiG-19), 200 J-8 (a twin-engine MiG-21 variant), and 300 Q-5 (a MiG-19 variant). The older models like the J-6/MiG-19 are a 1950s design, were being phased out, either because more modern aircraft entered service, or the older ones were just worn out, even though they do training flights nearly as much as Western aircraft.
The Chinese believe some of their older designs still have lots of useful life left. In particular, they are revamping many of their J-8s to be "smart" bombers. This is being done to take advantage of new smart bomb designs the Chinese have introduced in the last decade. These include laser and satellite (GPS) guided bombs. The J-8II has had a hard point added under the fuselage, and additional ones on the wings. A new radar, equipped to support finding and hitting, ground targets has been added. The new J-8 model can deliver laser or GPS smart bombs.
The J-8 itself was a failed design as it is less maneuverable than the original MiG-21 it was based on. Maneuverability was further degraded when carrying all those bombs. The J-8II is also being equipped for SEAD (Suppression of Enemy Air Defenses), carrying anti-radiation missiles to destroy enemy radars.
China is also pushing its J-8 fighter for export sales. Another new model, the J-8T, has a more modern radar and has been shown carrying a reconnaissance/electronic warfare pod. The J-8II is also a prime export product, along with lots of those expensive new Chinese smart bombs.
The J-8 is an 18-ton, two engine, variant of the MiG-21. This was China's first attempt at building their own aircraft design. But it was not a very original or successful effort. The J-8 first flew in 1969, and didn't get into service until 1980. It was quickly realized that this was a turkey.
Fewer than 400 were built. The F-8 carries about three tons of bombs, and is not very maneuverable. China decided to make the most of it, and used the J-8 as a reconnaissance and electronic warfare aircraft. Because of that the navy adopted it as well. It was a J-8 that collided with an American EP-3 reconnaissance aircraft off the coast in 2001. The J-8, which made the mistake of maneuvering too close to the much slower (propeller driven) EP-3, collided with it and crashed. The EP-3 survived and made an emergency landing in China, kicking off months of diplomatic tension.
By 2020 there were still about a hundred J-8s in service, mainly as interceptors. China found that more modern aircraft were more effective at using the Chinese designed smart bombs and missiles. The older Russian designs are being retired as quickly as possible and nearly all will be gone in the next five years. The Chinese air force will shrink a bit because new jet fighters can’t be built fast enough.