Airstair

Airstairs eliminate the need for passengers to use a mobile stairway or jetway to board or exit the aircraft, providing more independence from ground services.

Ventral airstairs are featured on most tail-engined airliners, such as the Boeing 727, the McDonnell Douglas DC-9, MD-80 and MD-90, the BAC 1-11, and the Yakovlev Yak-40/Yak-42 series, and are incorporated as ramps which lower from the fuselage.

The most common type of airstair is found in most business aircraft, regional jets, and other small airliners, which is a stair built into the inside of the main passenger door, which is lowered to the outside.

The mechanism is also quite heavy; as a result, many airlines have removed this system to reduce aircraft weight.

One version of on-board folding airstairs were designed by Winters Aircraft Engineering Company over 30 years ago.[when?]

Dow Aero[1] is the current STC holder, as listed on the FAA's Dynamic Regulatory System.

This was attempted on 24 November 1971 by an unknown hijacker, widely known as D. B. Cooper, who jumped from a Boeing 727 along with US$200,000 in ransom money.

Subsequently, a number of individuals carried out copycat hijackings against Boeing 727s and safely parachuted to the ground, although all were apprehended by the authorities.