History:
Designed in 1944, the I-250's Khalshchevnikov jet engine was of a simple design
with the compressor being driven off the Klimov piston engine, it did how ever
have a primitive variable exhaust nozzle, a novel feature in 1945. The aircraft's
first flight was on the 3/3/1945, the design was improved in 1947 to be called
the Mig 13. Unlike other mixed powered aircraft the I-250 was a success of sorts
as it managed the stay in service until 1950 with the Soviet Navy's Baltic and
Polar Fleet. Between 20 to 50 were made.