This little gem came out about 2 weeks ago on Steam. It's made by a small group of 5 developers and runs for about $20 (£10.99). Essentially, it's a multiplayer game in the vein of Wargaming's titles where you fly a helicopter and achieve map control by taking over firebases, occasionally shooting each other down.
It's also horribly addictive.
The PVE element to be frank is the best part of the game. You fly cooperatively with up to three other players and work together to fulfill dynamically selected objectives around the map, whether it's strafing tank convoys, dealing with infantry ambushes, or taking over firebases. They are also quite enjoyable to do solo, but combining different classes with others is where this shines. You also have PVP where you take over firebases and engage in dogfights for points.
You have three classes of helicopters: Scout, which spots for mortars and can reveal hidden units like infantry; Gunship which focuses on anti-vehicle and anti-structure firepower; and Assault which are transport choppers designed to take over bases as well as drop off special infantry like mortar teams and stinger infantry.
You create a squadron of three to use in each battle, and switch between them depending on what mission you need to perform.

Helicopters range in size from the colossal HH-53 Jolly Green Giant to the three-man OH-6 scout.
The nice thing about this game is the lack of grind - it took me about two days of playing to get to final tier content. Gameplay is quite polished, but in terms of maps and gameplay types it's quite low on content at the moment.