Klimov RD-500

Producing metric drawings and analyzing the materials used in the Derwent V went fairly quickly, but finding a substitute for the high-temperature, creep-resistant Nimonic 80 nickel-chromium alloy[1] was a more difficult challenge.

The main problem with the engine in service was with its turbine blades, 30% of which failed inspection due to recrystallization after casting.

The poor creep resistance of the KhN 80T alloy resulted in dangerous elongation of the turbine blades.

Up to 40% of the early production RD-500s had to be individually adjusted before delivery and the service life of the engine never approached the 100 hours demonstrated in the acceptance test.

[2] Production was canceled around 1950 in favor of the superior Klimov VK-1 turbojet based on the Rolls-Royce Nene.