China recently released photos and other information about the first production WTC-2000 aircraft. This is the export version of their JL-9 single seat jet trainer. The only known export customer is Sudan, which ordered six WTC-2000 in 2016. What is distinctive about the JL-9 is that it, and the WTC-2000 use a single Chinese WP-13 jet engine. This is a big deal because China is largely dependent on Russian jet engines for its warplanes. Efforts to build Chinese jet engines has been slow, especially when it comes to reliability. The 1.1 ton WP-13 is rated at 2,200 flight hours and is also used in the JF-17 China builds for Pakistan (and is largely assembled in Pakistan, the only customer so far).
The eight ton JL-9 is an upgraded version of the older JJ-7 trainer, which was based on the J-7 (a Chinese copy of the Russian MiG-21). The JL-9 has side air intakes, and a radar dome up front. It doesn't look a lot like a MiG-21, and is somewhat easier to fly. JL-9 has five hard points for additional fuel tanks, bombs or a 23mm autocannon pod. This makes is useful in training new pilots in ground attack techniques as well as providing export customers with an inexpensive attack aircraft. The export version can be equipped with non-Chinese electronics to suit customer requirements.
The JL-9 entered service in 2011 with the Chinese air force and navy. The JL-9 is several million dollars cheaper than the twin-engine JL-15 which is made by another Chinese firm and is now aimed at the export market (mainly as a light attack aircraft). Apparently, the Chinese believe that it's better, and cheaper, for new J-10 and J-11 pilots to learn in these aircraft, rather than spending more time in the pricey, but similar in performance, JL-15s.
The JL-9 is competing with a lot of more popular Western trainer designs. These are generally more expensive and have many satisfied customers. But the Chinese know how to buy their way into a market. The Chinese sell the JL-9 at a third or more less than comparable Western aircraft and the Chinese are willing to make modifications and, more importantly, sell to anyone who can pay.