The air forces of a nation fly and fight in the air. Airborne forces, transported to battle through the air, are primarily trained to fight on and for the ground. U.S. Army doctrine on the Tactics and Technique of Air-Borne Troops is set forth in Basic Field Manual FM 31-30, published May 20, 1942. For those unacquainted with this manual, the following official definitions may be helpful:

Air-Borne Troops--any transported by air.

Air-Landing Troops--troops carried in powered aircraft, or in gliders towed behind aircraft, who disembark after the aircraft or glider reaches the ground.

Parachute Troops--troops moved by air transport and landed by means of parachutes.

Several other definitions, as used by United States Army Air Forces, may be quoted from Army Regulations No. 95-35, of July 7, 1942:

Landing field--an area of land designated for the take-off and landing of aircraft.

Airdrome--a landing field at which military facilities for shelter, supply, and repair of aircraft have been provided.

Air base--a command which comprises the installations and facilities required by and provided for the operation, maintenance, repair, and supply of a specific air force.

Airport--a tract of land or water which is adapted for the landing and take-off of aircraft and which provides facilities for their shelter, supply, and repair; a place used regularly for receiving or discharging passengers or cargo by air.