Evacuation slide

An evacuation slide is an inflatable slide used to evacuate an aircraft quickly. An escape slide is required on all commercial (passenger carrying) aircraft where the door sill height is such that, in the event of an evacuation, passengers would be unable to step down from the door uninjured (Federal Aviation Administration requires slides on all aircraft doors where the floor is 6 feet (1.8 m) or more above the ground).

Escape slides are packed and held within the door structure inside the slide bustle, a protruding part of the inside of an aircraft door that varies with aircraft size, door size and door location. In many modern planes, to reduce evacuation time, evacuation slides deploy automatically when a door is opened in an "armed" condition. Modern planes often indicate an armed condition with an indicator light.

Many slides are also designed to double as life rafts in case of a water landing.

All large commercial aircraft have escape slides on the main doors of the plane, but some do not have slides over the wings, because when the flaps are fully lowered, the wings are low enough to the ground that passengers can evacuate safely. Some of these aircraft are the Embraer 190, Boeing 707, 717, 727 and 737. However, other aircraft require the use of overwing slides for the window exits to ensure that passengers can reach the ground quickly and safely. These include the Boeing 767, Boeing 757, and Airbus A320-series aircraft. Typically, overwing evacuation slides are not designed for use in ditching situations as they cannot be detached and will not operate, as the system is disabled by the aspirators on the slide taking in water, and Boeing recommends disarming the doors of a 747 before opening in a ditching situation.

Window exits usually come in two configurations:

Window exits are usually equipped with ditching or life lines. These may be attached to the inside frame of the window exit, or located in a nearby storage locker. One end has a buckle to connect to attachments on the aircraft's wings.

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