I still remember how I have played the Hell-Copter demo version with its two levels almost to death, back in 1998, despite the fact that it came out during the same time when Half Life was released, at least if I do remember correctly. Some of my classmates from that time also knew the demo of it and loved it just as much. It took me almost 1.5 decades, until I have found an old retail version of the full game.
The game itself is simple. You are looking down onto the top of your helicopter, yet it is not one of those sidescroller games, but a game with 3D terrain, 3D units and the freedom to fly where you want to, so you are able to finish the goals of the mission in the order that you choose for yourself. There are three helicopters, a light but fast one, a medium one and a heavy one. All three of them can be upgraded and the great thing is that you can replay previous missions and continue to gather points from those, so if a mission is getting too hard, you just play the previous ones, until your chopper is upgraded enough with better weapons and armor. Upgrading is also very needed, because the difficulty of the game rises with further missions. In all you receive so many enemies to destroy, ground and air ones, beautiful explosions and a quite realistic military setting, despite the fact that the game is an Arcade-like action game and not a helicopter simulation.
I do not know why this game has never received any successor or that no one talked about this game for very long, because it contains so many action-filled Arcade fun that it is great enough for a simple, yet very challenging experience. I really hope that one day GOG can get their hands on it and make it ready for modern Windows versions, which may be a tough work, but the simple, yet realistic feeling of its action gives this game something unique that I was unable to find in any other (helicopter) game, even today, in 2025. And I think that truly says it all how much this great game stands out.