As runway near-misses surge, radar that keeps planes apart is aging and unreliable

An American Airlines jet taxis below O’Hare’s new Satellite South air traffic control tower on Oct 14, 2015, in Chicago, Illinois. Keeping track of ground traffic at airports is particularly important at a time when runway-safety incidents appear to be surging. — Getty Images/TNS

A crucial safety system that’s relied on to avoid potentially fatal collisions at major US airports is aging and plagued by outages that have left travellers unprotected for months at a time. At some airports, it hasn’t ever been installed.

The technology – which tracks vehicles on or near runways to alert controllers before impending crashes – often uses decades-old radar equipment for which spare parts are difficult to find, according to government data and the president of the union representing air-traffic controllers.