Which helicopter inspired Bratukhin's early designs?

Short answer

The Focke-Wulf Fw 61: Soviet designer Ivan Bratukhin and his 1940 OKB-3 department were influenced by the success of that German side-by-side twin-rotor helicopter. All the bureau's designs repeated the layout of two rotors with separate engines on side outriggers.

Published: November 5, 2026 · Updated: November 5, 2026 · Edited by Above Ten Thousand · Editorial policy

Which helicopter inspired Bratukhin's early designs?

Bratukhin B-11 top view silhouette

The German model as reference

Soviet designer Ivan Bratukhin (1903-1985) and his 1940 OKB-3 department chose a different path, influenced by the success of the German Focke-Wulf Fw 61, a side-by-side twin-rotor helicopter. OKB-3 was a Soviet design bureau created in 1940 to develop helicopters, headed by Ivan Pavlovich Bratukhin, and over the following decade it built several experimental helicopters.

Two rotors on either side of the fuselage

All the bureau's designs shared the same basic layout: two rotors with independent engines mounted at the ends of outriggers projecting from each side of the fuselage. On the Omega, each rotor was carried by a long transverse lattice outrigger and was powered by its own engine, housed in a nacelle also located at the end of the structure. The Omega II, Bratukhin's second side-by-side twin-rotor design, used two nine-cylinder Kossov MG-31F radial engines rated at 350 hp (261 kW) each, mounted on the outside of the uncovered steel-tube lattice structure and linked by a synchronizing shaft.

Tests interrupted by the war

Tethered tests of the Omega began in August 1941 and revealed serious vibration and engine overheating problems. Before they could be addressed, OKB-3 was evacuated ahead of the German advance into the Soviet Union. Flight tests resumed in mid-1942, with the Omega still flying tethered into early the following year. The bureau was disbanded in 1951.