Design work on the Sparka was begun in 1937 and this led to construction of the first prototype the following year. By 1939, the first flyable form was readied as the "S-1" but the example lacked the proposed armament, wheeled undercarriage (skids were fitted instead), and installed just one of the two intended powerplants. A first-flight was recorded on January 29th, 1940. S-1 was then followed by "S-2" and this included all of the proposed components the S-1 lacked. In testing, the pair performed adequately - handling was a strong point - but was not as fast as expected and proved tricky when attempting take-off and landing actions.
The design was evolved into the ultimately-abandoned Bolkhovitinov "I" - with twin M-107 engines and other slight changes - and the Bolkhovitinov "D", a heavy bomber form which never saw the light of day. Other proposed forms related to the Sparka project included a dedicated attacker (with downward-firing heavy machine guns) and a dedicated interceptor (with upward-firing 37mm automatic cannon).
As tested, the Sparka managed a maximum speed of 354 miles per hour and ranged out to 435 miles. Nothing more came out of the project beyond the two aforementioned prototypes.
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