A potential disaster. That’s how one lawmaker described a recent incident where two airplanes got too close to for comfort in the skies above Melbourne, Australia. In the minutes prior, air traffic controllers were using a procedure specific to airports such as Melbourne that have crossing runways. Known as ‘Land and Hold Short,’ it entails having aircraft land and take off on one runway, while having those using the other ‘hold short’ of the crossing point. This ensures safe separation. In Melbourne however, both airplanes simultaneously aborted their landing attempts and continued flying straight ahead. This resulted in a ‘near-miss,’ industry lingo for a narrowly avoided collision. The incident has raised questions about how runways are designed, risk management, and the importance of sparing no expense when it comes to safety.

The modern-day airplane is a technological marvel. Its fuel tanks can hold thousands of liters of jet fuel, its belly several tons of cargo. When paired with the right navigation and engine technology, it can carry hundreds of passengers across continents and oceans. Making sure those passengers arrive safely at their destinations means keeping one airplane a safe distance away from another. However, keeping an airplane away from other airplanes is a more complicated proposition. This distinction is important. The scheduled air transport industry is more than 100 times larger today than it was seven decades ago. That means more airplanes using the same airports, often at the same time; all in a bid to cater to passenger demand that is growing at a rate of 5% annually. 

Meeting this demand requires infrastructure like passenger terminals, fuel depots and highways. Most importantly, it requires runways. Runways are the most important piece of real estate for an airport, an economic engine that affords global access. Wind direction is an important consideration when deciding where to build a runway because taking off and landing into the wind is safer than doing so when the wind blows at an angle from the direction of travel. An airport could build multiple runways that accommodate winds from every direction and place those runways far apart to minimize risk. But this means hefty land procurement and building costs that are ultimately passed along to cash-strapped airlines. Hence, crossing runways are chosen because they maximize the airport’s ability to accommodate aircraft in different (but not all) wind conditions, while minimizing the amount of physical space (and subsequently cost) associated with doing so. This choice also means greater care must be exercised when operating at these airports because airplanes tend to be spaced closer together.

Yet it is choice that has been made the world over. From New York to Amsterdam to Sydney, there is no shortage of high-profile hubs that have opted for crossing runway configurations. All have procedures in place to minimize risk; procedures that balance the need to be safe against the importance of running a fiscally viable operation. The effectiveness of these procedures may well explain why the likelihood of incidents such as that seen in Melbourne is believed to be as low as once every 175 years. The chances of a fatalities occurring as a result are even lower. In fact, bolstered by improvements in technology, policies and procedures, air travel today has become so reliable that by one estimate, a passenger could fly every day for an average of 123,000 years before being in a fatal crash.

Any incident involving loss of life is one incident too many. But bemoaning a lack of spending is an all-too-common response in the aftermath of such events. Following the Melbourne incident, a lawmaker was quick to espouse the virtues of adopting runway construction practices that while being considerably more expensive were reportedly safer. Yet, history is filled with examples of aviation enterprises that had flawless safety records but were fiscally unviable. Safety is important, but so is profitability. Industry sustainability requires both, in equal measure.