Hi,
This is from a Humble Bundle so winner will receive a Steam key.
The bundle includes Take on Helicopters and Take on Helicopters: Hinds

Take on Helicopters - Built upon over 10 years of experience in cutting-edge simulator development, Take On Helicopters immerses players within beautifully rich landscapes and an authentic flight model.
The User Reviews are Mixed and the game includes single player. multi-player and co-op.

Good luck everyone :)