3D Helicopter Simulator by Sierra - 1987
3D Helicopter Simulator (1987) by Sierra

Released in 1987, this sim must have been one of the first sims to support head to head play via a modem. For it's time it looked outstanding with 3 dimensional polygon choppers and scenery.

3D Helicopter Simulator by Sierra - 1987

3D Helicopter Simulator by Sierra - 1987