Runway incursion


A runway incursion is an incident where an unauthorized aircraft, vehicle, or person is on a runway or runway protected area. Under some interpretations, a runway incursion
also exists when an aircraft crosses into an ILS protected area or approach protected area when active. Any such incursion adversely affects runway safety, as it creates the risk that an airplane taking off or landing will collide with the object, distract the non-infringing flight crew, or interfere with navigational signals such as the glideslope or localizer. "Runway Incursion" is defined by the International Civil Aviation Organization on April 27, 2006, as:
Any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle, or person on the protected area of a surface designated for the landing and take-off of aircraft.

In October 2007, the Federal Aviation Administration dropped its own definition of "runway incursion" and adopted the above. The difference between the two was "that ICAO defines a runway incursion as any unauthorized intrusion onto a runway, regardless of whether or not an aircraft presents a potential conflict. For the FAA, an incident without an aircraft in potential conflict– such as an unauthorized aircraft crossing an empty runway– was defined as a 'surface incident' and not a runway incursion."
There are 3 types of runway incursions with 4 levels of severity that the FAA uses to classify incidents.
Operational Incidents - Action of an Air Traffic Controller that results in: Less than required minimum separation between two or more aircraft, or between an aircraft and obstacles, or Clearing an aircraft to take off or land on a closed runway.
Pilot Deviations - Action of a pilot that violates any Federal Aviation Regulation, Example: a pilot crosses a runway without a clearance while en route to an airport gate.
Vehicle/Pedestrian Deviations - Pedestrians or vehicles entering any portion of the airport movement areas without authorization from air traffic control.
The 4 levels of severity are as follows:
Category D - Incident that meets the definition of runway incursion such as incorrect presence of a single vehicle/person/aircraft on the protected area of a surface designated for the landing and takeoff of aircraft but with no immediate safety consequences.
Category C - An incident characterized by ample time and/or distance to avoid a collision.
Category B - An incident in which separation decreases and there is a significant potential for collision, which may result in a time critical corrective/evasive response to avoid a collision.
Category A - A serious incident in which a collision was narrowly avoided.
Accident - An incursion that resulted in a collision.
The Airport Surface Detection Equipment, Model X and the Airport Movement Area Safety System are computerized systems that are intended to alert air traffic controllers to the potential for a runway incursion.

Serious and fatal runway incursions