The Tumansky R-13, designed by Sergei Alekseevich Gavrilov, is a development of the successful Tumansky R-11 engine. It is a two-spool axial-flow turbojet featuring a new five-stage high-pressure compressor, new combustion chamber design to facilitate restarting the engine at high altitudes, new afterburner, and greater use of titanium components. It is used by MiG-21M, MF, SM, and SMT, and Sukhoi Su-15M and TM. R-13 is also built in China as LM WP13, and experienced similar fate like Tumansky R-11: originally, both were supposed to be licensed built in China, but due to Sino-Soviet split, all Soviet technical support was withdrawn and China was forced to do the job itself. Under the leadership of the general designer Mr. Jiang Hepu, both R-11 and R-13 were successfully built in China on its own, and were given the designation of WP-7 and WP-13 respectively.