The Beriev Be-4 (originally designated KOR-2) was a reconnaissance flying boat built to operate from Soviet warships during World War II.
The new aircraft, with the in-house designation KOR-2, first flew on 21 October 1940 at the Beriev factory in Taganrog.
Testing continued through January 1941, when series production was ordered under the designation Be-4, at a factory near Moscow.
The factory was dismantled, and evacuated to Omsk, then to Krasnoyarsk, where production resumed in May 1943 to the end of 1945.
The Be-4 was placed into operational service with the Russian Black Sea Fleet from 1942, where it was used for coastal reconnaissance, anti-submarine and transport duties.