V-250 - a giant helicopter project inspired by the American XH-17 helicopter. With a lifting capacity of 250 tonnes and a take-off weight of 560.5 tonnes, it was to have a rotor with jet engines at its end with a diameter of 108 metres. To validate the design, Kamov's office ordered an experimental V-7 helicopter from Mil. After the failure of the V-7 helicopter, the project was ultimately not implemented.