The topic of ground safety extends to not only the risk of runway incursion, with the potential for ground collision, but in addition runway excursion. In 2023 there have been several high severity runway incursion/loss of separation events that could have resulted in the collision of two aircraft. The SIRM reviewed the topic of runway safety and explored the associated safety issues.
The condition of the runway paved surface is critical for safe landing and take-off operations. Discussions on the runway condition included:
The presence of aerodrome navigation aids is hugely variable across the world regions. Some aerodromes provide ground-based navigations aids that permit precision approaches, such as ILS. While for other aerodromes the ground-based aids may either be unreliable or not even fitted.
In the absence of ground-based navigation aids, terrestrial navigation aids can be utilized providing there is a published RNAV approach procedure for the aerodrome and the aircraft is appropriately equipped. It was highlighted that GNSS interference in the form of spoofing or jamming can make this approach option unavailable, however.
It’s vital that flight crew have an accurate and up to date awareness of both the runway and apron surface condition – particularly with braking action adversely effected by contaminated surfaces, from the presence of either ice or snow. Varying reporting requirements for the taxiway v the runway can result in the flight crew not having the full picture – leading to a situation where braking action is insufficient, and the potential for a taxiway or runway incursion or even a collision with another aircraft, obstacle, or ground vehicle.
Effective communication between flight crew and air traffic controllers is fundamental to ensure critical information is conveyed and understood. Factors that may hinder the delivery or understanding of an instruction, such as a clearance to enter a runway or a take-off clearance, include:
Mitigation of a particular safety issue can on occasion lead to risk transfer. The group discussed an example of this and highlighted that:
“During the approach phase the flight crew focus can be prioritized on avoiding a deep landing or overshoot to such an extent that the aircraft descends or drifts below the glide slope. This has the potential to introduce a condition where the aircraft could land short of the touch down zone, or even undershoot the runway paved surface."
It was highlighted that differences in definitions and terminology can create confusion or lead flight crew to make incorrect assumptions about the level of air traffic service available at an aerodrome. For example, the term ‘controlled’ aerodrome in the US means that as a minimum a weather observer is present, but there is not necessarily an air traffic service available. While in other parts of the world, ‘controlled’ is indicating that some form of air traffic service is available.
Factors that typically drive reporting of safety events across the aviation ecosystem in general are also applicable within the aerodrome environment. A key driver to reporting being that if someone makes a mistake, they are more likely to report this mistake if there is someone who witnesses the error. To fully understand and mitigate the issues associated with runway safety, the importance of a just culture was highlighted to encourage the reporting of safety events, regardless of who might witness the situation.