Airdrop

An airdrop is a type of airlift, developed during World War II to resupply otherwise inaccessible troops, who themselves may have been airborne forces. In some cases, it is used to refer to the airborne assault itself. Early airdrops were conducted by pushing small crates with parachutes out of the aircraft's side cargo doors. Later cargo aircraft were designed with rear access ramps, lowerable in flight, that allowed large platforms to be rolled out the back.

As aircraft grew larger, the U.S. Air Force and Army developed "low-level extraction" — allowing tanks and other large supplies to be delivered, such as the M551 Sheridan or M2 Bradley. Propaganda leaflets are also a common item to airdrop.

In peacekeeping operations or humanitarian aid situations, food and medical supplies are often airdropped from United Nations and other aircraft.

Types of airdrop

The Type of airdrop refers to the rate at which the airdrop load descends to the ground. There are three main types of airdrop, and each type may be performed via several methods.

* Low-Velocity Airdrop (also known as LAPES) is the delivery of a load involving cargo parachutes that are designed to slow down the load as much as possible to ensure it impacts the ground with minimal force. This type of airdrop is used for delicate equipment and larger items such as vehicles.
* High-Velocity Airdrop is the delivery of a load involving a parachute meant to stabilize its fall. The parachute will slow the load to some degree but not to the extent of a Low-Velocity airdrop as High-Velocity airdrops are used for durable items like MREs.
* Free Fall Airdrop is an airdrop with no parachute at all. Common uses of this type of airdrop include the delivery of humanitarian aid supplies and leaflets used in Psychological warfare.

Methods of airdrop

The Method of airdrop refers to the way the load leaves the aircraft. There are three main methods of airdrop used in military operations.

* Extraction airdrops use an extraction parachute to "pull" the load out of the aft end of the airplane. In this method, an extraction parachute is deployed behind the aircraft which pulls the load out and cargo parachutes are deployed to slow the load. Extraction drops are invariably Low-Velocity airdrops.
* Gravity airdrops use gravity in the sense that the attitude of the aircraft at the time of the drop causes the load to roll out of the plane like a sled down a hill. The most common use of a gravity airdrop is for the Container Delivery System (CDS) bundle.
* Door Bundle drops are the simplest of airdrop methods. In a door bundle airdrop, the Loadmaster simply pushes out the load at the appropriate time.

References

cite book
title = Technical Order (TO)13C7-1-11 Airdrop of Supplies and Equipment: Rigging Containers
publisher = Department Of The Air Force
month =September | year =2005

cite book
title = Technical Order (TO)13C7-1-5 Airdrop of Supplies and Equipment: Rigging Airdrop Platforms
publisher = Department Of The Air Force
month =August | year =2001

See also

* Loadmaster
* Winged tank
* Operation Manna

External links

* [http://www.army.mod.uk/13aaregt/organisation/47_air_despatch/index.htm 47 Air Despatch Sqn RLC] The British Army's only remaining unit specialising in airdrop.