Boeing AH-64 Apache in the context of "Night vision device"

Army aviation is military aviation that is organized as a sub-branch under the command of an army, separate from a nation's dedicated air force. Army aviation units, sometimes described as air corps, are typically attached as a part of to a ground force and tasked to tactically assist its land warfare by providing close air support, rapid insertion, reconnaissance and logistics for front line ground operations. They usually comprise VTOL aircraft such as military helicopters, as well as gyrocopters, light fixed-wing attack aircraft and unmanned aerial vehicles (drones), and historically also aerostats such as military balloons and airships.

Prior to the establishment of separate national air forces, many armies had aviation units, which as the importance of aviation increased, were spun off into independent branches of the military. As the separation between a nation's ground and air forces led to a divergence of priorities, many armies sought to re-establish their own aviation branches to best serve their own organic tactical needs.

A helmet-mounted display (HMD) is a headworn device that uses displays and optics to project imagery and/or symbology to the eyes. It provides visual information to the user where head protection is required – most notably in military aircraft. The display-optics assembly can be attached to a helmet or integrated into the design of the helmet. An HMD provides the pilot with situation awareness, an enhanced image of the scene, and in military applications cue weapons systems, to the direction their head is pointing. Applications which allow cuing of weapon systems are referred to as helmet-mounted sight and display (HMSD) or helmet-mounted sights (HMS).

An armed helicopter is a military helicopter equipped with aircraft ordnance. Most commonly, it is used for attacking targets on the ground. Such a helicopter could be either purposely designed for a ground-attack mission—in which case it would be more specifically categorized as an attack helicopter—or may have been previously designed for other uses, such as utility, air cargo, aerial reconnaissance, etc., with the weapons mounts being modifications, rather than part of the design of the helicopter. The purpose of the modification to an armed helicopter configuration can be field expediency during combat, the lack of military funding to develop or purchase attack helicopters, or the need to maintain the helicopter for missions that do not require the weapons.

Specialized armed helicopters fly from ships at sea, and are equipped for anti-submarine warfare or strikes with anti-ship missiles.