First tethered flight of the Bratukhin Omega II/G-2 helicopter
Saturday, September 30, 1944
The Omega II/G-2 was a lateral twin helicopter. The aircraft made its first public appearance during the Tushino Air Display on Soviet Aviation Day on Aug. 18, 1946.
Note: The actual day in September is unknown
Source: "Bratukhin Omega II/G-2 Lateral-Twin Helicopter", Ken Bartie, VFS web page, Last accessed Feb 26, 2020