Runway Excursions Research - ATSB
Runway Excursions Research - ATSB
The Australian Transport Safety Bureau (ATSB) Transport Safety Report on Runway Excursions is a study comprising two parts: Part 1 - A worldwide review of commercial jet aircraft runway excursions and Part 2 - The impact of a major runway excursion accident from an Australian perspective.
The first part of the report provides a statistical picture of runway excursion accidents over a 10-year period - how frequently they occur, why they occur, and what factors contributed to those accidents. The second part of the report discusses the impact of a major runway excursion accident from an Australian perspective, and identifies the safeguards that exist at Australian airports to safely control a runway excursion if one occurs.
According to Part 1 of the ATSB Report, approximately a quarter of all incidents and accidents in air transport, and 96 per cent of all runway accidents are attributed to runway excursions. Runway excursions involve aircraft running off the end of the runway (overrun) or departing the side of the runway (veer-off).
The first part of the report identifies 141 runway excursion accidents involving the worldwide commercial jet aircraft fleet between 1998 and 2007. Those accidents resulted in 550 fatalities. Of those 141 accidents, 120 occurred during the landing phase of flight. An in-depth analysis of those 120 accidents is conducted in order to identify the types of flight crew technique and decision-related, flight crew performance-related, weather-related, and systems-related factors (accounted for 71 per cent of 343 factors) that contribute to runway excursions.
Most Common Contributing Factors Identified by the Report
The classification of factors contributing to runway excursion accidents established by Flight Safety Foundation (FSF) is used to categorise the most common types of factors contributing to the runway excursions identified in the ATSB report.
According to the report, the most common contributors to these types of accidents and incidents are:
Flight crew technique and decision-related factors
- flying an unstabilised approach
- landing too fast, too far down the runway, or conducting an extended flare
- delayed or incorrect braking action
- not conducting a missed approach or go-around despite unsafe landing conditions
Flight crew performance-related factors
- less than adequate flight crew awareness of procedures or systems
- spatial disorientation, visual illusions, fatigue and task saturation
- less than adequate operator procedures for assessing whether weather or runway conditions are safe for landing
- less than adequate awareness of the effect of weather and runway conditions on actual landing roll-out length
- operating on a wet or contaminated runway
- landing in heavy rain, wind shear, excessive tailwinds or crosswinds
- inconsistent reporting of runway conditions and braking action at airports across the world
- aquaplaning on a wet runway
- malfunction or unexpected action of braking systems.
In most runway excursions, any one or combination of these factors can lead to an unsafe outcome because of non-adherence to standard operating procedures, or less than adequate operator procedures for safe approaches and landings. In the majority of the accidents studied, less than adequate procedures or non-adherence to procedures led to:
- an unstabilised approach, resulting in a long, fast, or otherwise unsafe landing; or
- a landing in poor weather conditions with unsuitable runway conditions for the aircraft type, resulting in a loss of control on the runway.
- RE Reports and Statistics:
- RE Operational Issues:
- Landing Distances (see Factors Affecting Actual Landing Distances);
- Rejected Take Off;
- Wrong Runway Use.