Runway excursions are behind more than a third of all aviation accidents, yet many fail to understand the causes and mitigation options. That is why FlightSafety is putting particular focus on the phenomenon in its pilot training
Of all the many procedures pilots practise regularly in the simulator, and execute each time they fly, landing their aircraft correctly on a designated and clearly marked landing strip might seem to be among the most straightforward and least troublesome.
Yet runway excursions – defined as any time an aircraft inadvertently leaves the runway paved surface – remain a significant operational risk for the industry, accounting for more than a third of all aviation accidents annually. They can happen to the most experienced aviator.
FlightSafety International is on a mission to not just impress on the industry the seriousness of the problem – on average, two runway excursions occur each week worldwide – but to provide pilots and operators with the training tools and mental disciplines to avoid them.
While not all excursions lead to injuries, fatalities or significant damage to the aircraft, “once you depart the side or end of the runway, there are a wide range of potential outcomes,” remarks Richard Meikle, executive vice- president operations and safety for FlightSafety International.
So why do they take place? Sometimes complacency plays a part. You might imagine, for example, that the risk of runway excursions is lower in summer than in winter, when at many airports fog, ice and snow are a regular hazard. However, the opposite is the case.
“One of the reasons is that in the warmer, lighter months, visual approaches are more common and pilots don’t always use the approach aids to establish the aircraft on the optimal flightpath to the runway, and pilots also tend to become more relaxed about the risks and underestimate the influence of water on the runway after a rain shower,” says Meikle.
Another reason – what psychologists call frequency gambling – is the natural human tendency to ignore warnings about a behaviour because on multiple occasions we have done it without consequences. Think motorists breaking the speed limit or continuing through traffic lights about to turn red.
In aviation, this might involve a pilot failing to execute a go-around after not being on speed as the aircraft approaches the runway threshold because in every other instance the outcome has been fine. “The pilot community are often reluctant to make a decision to alter something we know is not quite right because we may have gotten away with it previously because there was enough margin. That works until the day the margin isn’t enough to absorb the deviation, and there is no rewind button in real-world operations,” says Meikle.
Another cognitive habit, continuation bias – where we stick with an original plan despite changing circumstances – may also lead to excursions. This is often the case in low approaches when – despite a go-around being possible and advisable – a pilot will persevere with trying to get the aircraft down.
“In those situations, we need to ensure that the pilotis thinking it’s still okay to go around,” says Meikle. “It’s more than satisfying the regulator. It’s all about ensuring confidence with executing a go-around in the very low altitude environment.”
Displaced thresholds – a threshold located at a point other than the designated start of the runway, reducing the available length available for landings – is a risk factor too. Data shows that of the top ten runways for excursion risk, seven have displaced thresholds.
Although there is not a regulatory requirement for pilots to train for such landings, it is very much part of the FlightSafety syllabus. “We just think it is the right thing to be teaching people the real-world threats, not just the checking standards. Pilots have to be prepared for the visual illusions and having the knowledge of this type of threat increases safety margins,” says Meikle.
At the heart of the FlightSafety approach to training pilots to recognise warning signs and mitigate risks of potential runway excursions is data. The company carried out a study last year into runway excursions around the world including more than 125 in 2022 alone. It came up with some interesting findings.
“There is no rewind button in realworld operations”
Richard Meikle, executive vice-president operations and safety, FlightSafety
Thirty-five percent of excursions resulted in substantial damage or destruction of the aircraft; going off the side of the runway was more prevalent than off its end; and the highest risk runways were those with landing distance available lengths of between 5,000ft (1,524m) and 6,000ft.
The research also discovered that unstable approach, weather/wind and mechanical issues were the biggest contributing factors, with quartering tailwinds, crosswinds, wind shifts and other weather variables key factors in just under a quarter of runway excursions.
One in four runway incursions involved mechanical issues or failures, such as a blown tyre, locked brakes, asymmetric reverse thrust, or hydraulic system failures. These usually led to loss of directional control during landing roll out.
FlightSafety’s training – modelled on these findings and other data – includes emphasis on executing a stable approach and precisely delivering the aircraft to the runway, as well as increasing situational awareness during a stabilised approach to notice immediately any flight path deviations or environmental changes.
The training also urges particular attention when it comes to runways within the 5,000ft to 6,000ft range or within 1,500ft of margin over computed required landing distance for aircraft type, particularly in wet or contaminated conditions.
When lateral and/or vertical flightpath deviations cannot be corrected immediately with small control inputs, or if there is any doubt over the approach or landing, the training focuses on executing a go-around, even if the threshold is passed, so long as a pilot is appropriately prepared.
FlightSafety began incorporating a focus on runway excursion risks into its regular training in early 2022, and plans to refresh the syllabus this year. “We will move into different areas that the data is pushing us into, but until runway excursion rates lower, we will keep a strong focus on this topic,” says Meikle.
The main message it wants to drive home is that no pilot – no matter how experienced – is immune to having a runway excursion. However, a solid understanding of the risks and mitigation strategies, combined with rigorous recurrent training, can prepare pilots to minimise the probability of this stubbornly persistent hazard.
“Understanding the threats and appropriate mitigations is what separates a great day of flying from an incident or accident. We want to give pilots all the tools and practical solutions they need to reduce their risk of having a bad day,” says Meikle.