Heavy-lift helicopter

Short-haul flight:	<3 hours
Medium-haul flight:	3 to 6 hours
Long-haul flight:	>6 hours

Military transport aircraft or military cargo aircraft are typically fixed wing and rotary wing cargo aircraft which are used to airlift troops, weapons and other military equipment by a variety of methods to any area of military operations around the surface of the planet, usually outside the commercial flight routes in uncontrolled airspace. Originally derived from bombers, military transport aircraft were used for delivering airborne forces during the Second World War and towing military gliders. Some military transport aircraft are tasked to perform multi-role duties such as aerial refueling and, rescue missions, tactical, operational and strategic airlifts onto unprepared runways, or those constructed by engineers.

Fixed-wing transport aircraft are defined in terms of their range capability as strategic airlift or tactical airlift to reflect the needs of the land forces which they most often support. These roughly correspond to the commercial flight length distinctions:

A more specialised role of a cargo aircraft is that of transporting fuel in support of other aircraft with more limited flight endurance such as fighters or helicopters. Smaller cargo aircraft, known as "utility", are often used to transport military communications equipment as temporary or permanent platforms, and in the command role by providing airborne command post or as an air ambulance.

Military transport helicopters are used in places where the use of conventional aircraft is impossible. For example, the military transport helicopter is the primary transport asset of US Marines deploying from LHDs and LHA. The landing possibilities of helicopters are almost unlimited, and where landing is impossible, for example densely packed jungle, the ability of the helicopter to hover allows troops to deploy by abseiling and roping.

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Wikipedia