UEC initiates second stage of testing the VK-650V demonstrator engine Rostec Press Release | July 21, 2021 Estimated reading time 2 minutes, 56 seconds. Demonstrator prototype of VK-650V engine developed by UEC-Klimov, subsidiary of the United Engine Corporation of Rostec, has reached the second stage of its testing program. The engine was exhibited at the International Aerospace Salon MAKS-2021. A prototype of the VK-650V engine was exhibited at the International Aerospace Salon MAKS-2021. Rostec Photo VK-650V has recently completed an intermediate stage of its testing program, covering tests of its individual components and update on its actual performance characteristics. Now the engine was passed on to second stage of the program. UEC-Klimov will proceed with testing the prototypes for required performance and preparing them for the qualifying stages.