The Disaster Waiting at the End of the Runway
Commercial aviation has achieved something remarkable. Millions of people routinely climb into machines weighing hundreds of tonnes, accelerate to around 250 kilometres per hour along a strip of concrete and disappear into the sky with scarcely a thought about whether they will arrive. The reason we can treat this extraordinary activity as ordinary is that modern aviation has built layer upon layer of safety procedures designed to prevent a single human mistake from becoming a catastrophe.
That is why the recent sequence of runway incidents at Sydney Airport deserves more attention than another round of reassuring statements that flying remains statistically safe. Aviation expert Graham Wild's analysis of 22 years of Australian data, published by The Conversation, concludes that runway collisions and near-misses have become more frequent. The trend is especially concerning because runway accidents occupy an unusual place in aviation risk: they may be uncommon, but when two large passenger aircraft actually collide at take-off or landing speeds, the consequences can be appalling.
The recent Sydney incidents provide an uncomfortable glimpse of how the layers can begin to fail. On July 27, air traffic control cleared a Boeing 737 to cross runway 34L while a QantasLink Dash 8 was still completing its landing roll on that runway. Controllers detected the conflict and warned both crews, and the 737 stopped after passing the holding point. The Australian Transport Safety Bureau classified the occurrence as a serious incident involving a runway incursion, procedural error and breakdown of coordination.
Another incident occurred on August 9. According to Airservices Australia, a Virgin Australia 737 was initially cleared for take-off while a Qantas aircraft was crossing the runway from a taxiway. A supervising controller immediately recognised the conflict and ordered the take-off clearance cancelled. The Virgin aircraft remained at the beginning of the runway, about 1.3 kilometres from the Qantas aircraft, and Airservices maintains that the pilot had not begun the take-off roll. That was therefore not nearly a collision in the cinematic sense, but it was another occasion on which an incorrect clearance had to be caught by another layer of the safety system.
This distinction matters. There is no justification for telling Australians that aircraft are presently missing one another by metres at Sydney every week. Some recent occurrences have involved substantial safety margins and are still being investigated. But neither should a pattern of incorrect clearances, runway incursions and breakdowns of coordination be dismissed merely because the safety system ultimately worked.
The disturbing question raised by Wild's longer-term analysis is whether the frequency of such events is increasing. Looking across more than two decades of Australian occurrence data, he reports an upward trend in runway collisions and near-misses. The ATSB's underlying national database extends back to July 2003 and contains accidents and incidents reported under Australia's mandatory occurrence-reporting system.
There is an important statistical caution here. More reported incidents do not automatically mean that every individual flight has become more dangerous. Traffic volumes change, reporting practices change, airport operations change, and the number of aircraft movements matters when interpreting raw occurrence counts. Nor does an increasing number of runway occurrences mean that a catastrophic collision is imminent. Rare-event statistics simply cannot tell us that.
But aviation safety has never been built on waiting until bodies provide definitive statistical proof. Its philosophy is almost exactly the opposite. A near-miss is valuable because it reveals a pathway to catastrophe without requiring anyone to die. Investigators ask what would have happened if the controller had noticed the conflict ten seconds later, if the pilot had misunderstood an instruction, if visibility had been poor, if an aircraft had already begun accelerating, or if one more protective layer had failed. Every incident is, in that sense, a free lesson purchased without casualties.
And we already know what the ultimate failure can look like. The worst aviation accident in history occurred not in the sky but on a runway. At Tenerife in 1977, two Boeing 747s collided at Los Rodeos Airport. One was accelerating for take-off while the other remained on the runway in fog. Five hundred and eighty-three people died. It remains a terrifying demonstration of how communication problems, human judgement, airport conditions and procedural failures can align until two perfectly functional aircraft become instruments of mass death.
Imagine the modern Australian equivalent at Sydney. A fully loaded wide-body aircraft might carry several hundred passengers and crew and contain tens of tonnes of aviation fuel. Another aircraft could be landing or crossing the runway. A departing jet near rotation speed has enormous kinetic energy and very little time or distance in which to stop. A high-speed collision could rupture fuel tanks, tear open fuselages and produce an intense post-impact fire.
The immediate casualty toll could reach hundreds. Airport rescue and firefighting crews would respond within minutes, but their task could be overwhelming: burning fuel, wreckage scattered across intersecting runways, injured passengers attempting evacuation, slides deployed into smoke and fire, and potentially two aircraft requiring simultaneous rescue.
The disaster would not necessarily stop at the airport boundary. Sydney Airport is embedded within a densely developed metropolitan area. The precise consequences would depend entirely on where and how a collision occurred, but wreckage or an aircraft departing the paved surface could create hazards beyond the people aboard the aircraft themselves.
Then would come the paralysis of Australia's aviation system. Sydney is the country's busiest airport and a central node of the domestic network. Closing major runways, or potentially the entire airport, would immediately disrupt flights across Australia. Aircraft already inbound would have to hold, divert or return. Domestic schedules would unravel as aircraft and crews ended up in the wrong cities. International passengers would be stranded across several continents.
The economic consequences would extend well beyond airlines. Sydney Airport connects business travel, tourism, air freight and international supply chains. A prolonged closure following a major collision would affect hotels, freight companies, exporters, conferences and thousands of businesses dependent upon predictable movement through Sydney. The investigation and physical recovery could take months even if normal operations resumed much sooner.
There would also be consequences for confidence. Commercial aviation depends upon passengers believing, correctly, that an extraordinarily complicated system is nevertheless extremely safe. A catastrophic runway collision following a publicly visible sequence of near-misses would immediately raise the question nobody in aviation would want to answer: were there warnings that were not acted upon strongly enough?
That is why the present moment matters. Airservices says safety is its highest priority and stresses that the recent Sydney incidents involved different circumstances and stakeholders. That is an important caution against forcing unrelated occurrences into a single explanation before investigations have been completed. Airservices is cooperating with the ATSB investigations, and in the August 9 case it says the supervising controller caught the erroneous clearance immediately.
Yet aviation accidents themselves commonly involve different circumstances converging. An earlier ATSB investigation into a 2019 Sydney incident illustrates the problem. A departing Airbus A330 and a Boeing 737 conducting a missed approach came within about 0.42 nautical miles horizontally and 508 feet vertically. The investigation subsequently identified deficiencies involving procedure design, risk management, controller training and even incorrectly programmed missed-approach points in flight-management computers. No single spectacular blunder explained everything. Multiple weaknesses progressively reduced the safety margin.
Airservices subsequently redesigned the runway 34R missed-approach procedure to increase separation from departing aircraft. That is exactly how a mature safety culture should work: identify the pathway revealed by an incident and close it before somebody discovers the same problem under less forgiving circumstances.
The same philosophy should govern the present cluster of incidents. If staffing levels are contributing, fix them. If fatigue is involved, address it. If controller training or supervision needs improvement, improve it. If Sydney's extraordinarily complicated runway and taxiway environment creates recurring opportunities for confusion, redesign procedures wherever possible. If technology can provide another independent warning before an aircraft enters an occupied runway, determine whether it should be strengthened or expanded.
The wrong response would be complacency based upon the fact that nobody has died. Nobody dying is precisely what a near-miss gives us: an opportunity to discover the weaknesses in a system while there is still time to correct them.
Flying in Australia remains remarkably safe, and nothing in these data justifies panic about boarding an aircraft tomorrow. But safety records are historical achievements, not laws of nature. Every generation of controllers, pilots, regulators and airport managers has to recreate that safety every day.
A major runway collision at Sydney would be one of the worst disasters in modern Australian history. It could kill hundreds, devastate families, paralyse the country's principal aviation hub, cost billions and destroy public confidence painstakingly accumulated over decades.
If the warning signs really are becoming more frequent, the time to discover why is not after investigators begin collecting pieces of two aircraft from the same runway. It is now.
https://theconversation.com/airport-runway-collisions-and-near-misses-are-happening-more-frequently-22-years-of-data-show-290158
