Landing zones

In military terminology a landing zone (LZ) is an area where aircraft can land.

In the United States military, a landing zone is the actual point where aircraft, especially helicopters, land (equivalent to the commonwealth landing point.)

In commonwealth militaries, a landing zone is the cartographic (numeric) zone in which the landing is going to take place (e.g., a valley). The landing area is the area in which the landing is going to take place (e.g., the field where the aircraft are to land). The landing point is the point on which aircraft are going to land (e.g., a point of the field). Each aircraft has a different landing point.

Landing areas are most commonly marked by coloured smoke. The standard procedure is for troops already on the ground at the landing area to "pop smoke" (set off a smoke grenade). The aircraft pilot(s) radio back when the smoke is spotted and what colour smoke they see. Troops on the ground then respond with what colour the smoke should be. Smoke of a different colour can mean that the landing area has been discovered and compromised by the enemy, and the pilot will usually have the authority to cancel any landing.

The United States used LZs to a greater extent in the Vietnam War than in other wars because of the widespread use of helicopters, which provided increased mobility and rapid transportation of forces in Vietnam. In turn, this resulted in extensive use of landing zones in this conflict. LZs could be temporary, being little more than a clearing in the jungle or a clearing made using special munitions, such as commando vault bombs, which cleared everything in a diameter of 150 feet. Other LZs were permanent or semi-permanent built with more deliberate construction.

The Soviet Union and Coalition forces also used LZs extensively because of the rugged terrain and distances traveled during wars in Afghanistan.

LZs operated by the First Cavalry Division, especially in War Zone C in 1968 and 1969, were often established for specific operations or to draw out the North Vietnamese Army (NVA) units thought to be operating in that area. When a sizeable enemy force was located, it could be decisively engaged, forced to move on, or if determined to be elsewhere, the LZ would be abandoned for a new location after a successful mission.

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