Choplifter HD is a reboot of the Choplifter series from the eighties and early nineties with the cooperation of the original designer Dan Gorlin. Just like the original games it is a side-scrolling shooter where the player controls a helicopter through a variety of attack and rescue missions. The helicopter can still only be moved over two axes, but the graphic design is entirely in 3D. There are different helicopters available that are unlocked gradually. They have statistics based on passenger capacity, armor, fuel, weaponry and speed.
As in the original titles missions often involve rescuing people. This is done by landing close to them so they can board the aircraft and then be brought back to the base. The main weapon for attacking is a mini-gun with free aim in any direction. Even though there is an unlimited amount of ammo, constantly firing is not possible due to overheating, so it has to be done in shorter bursts. The player also has access to a limited amount of rockets for much more damage. By tapping a key or a button enemies in the foreground of the environment can be marked to aim in that direction. This makes the helicopter face left or right.
A level map is shown as a horizontal bar near the top of the screen where targets and P.O.W.'s for transport are marked. Some are wounded and those need to be picked up first. In some cases that means the helicopter needs to boost to make it home quickly, which drains the fuel at a faster rate. Fuel is limited and refueling is done at a station or at the home base. It is possible to return at any time but there is a time limit for each mission. Next to the main mission objective there are hidden ones that are only discovered while a mission is in progress.