airstair

An airstair is a retractable set of steps that can be deployed from the side of an aircraft to allow passengers to board and disembark. These are typically found on smaller aircraft such as turboprops and some regional jets. Larger aircraft, especially those designed for commercial airline service, usually rely on jet bridges or mobile stairs for passenger access.

The airstair mechanism is usually powered hydraulically or electrically. When not in use, the airstair is stored within a compartment in the aircraft's fuselage, maintaining a clean aerodynamic profile. Deployment is typically a straightforward process, allowing for relatively quick boarding and deplaning, especially at airports lacking extensive ground support equipment.

The presence of an airstair can offer flexibility in aircraft operation. It reduces reliance on external ground infrastructure, making the aircraft more self-sufficient and capable of operating from less developed airfields. However, the weight and complexity of the airstair system can slightly increase the aircraft's overall weight and maintenance requirements. While common on certain types of aircraft, airstairs are less prevalent on large airliners due to the volume of passengers and the efficiency of jet bridges.