In your office, there might be an ancient, dusty computer lurking in a corner that no one remembers to take to the electronics recycling place. Maybe it runs some scary-old operating system like Windows 95, and you wouldn’t use it for a mission-critical function. Would you? At Orly airport outside of Paris, France, the breakdown of a program that provides weather and visibility updates to pilots grounded dozens of planes. The problem: that program only runs on Windows 3.1.

The computer, Vice News explains, has an important use in the business of getting planes out the door: air traffic control uses it to send weather information to pilots. That was crucial on the day of the weather computer breakdown, since there was heavy fog around the airport, and the computer runs a program called DECOR, which tells pilots how far down the runway they can see at the moment. That’s useful when it’s foggy.

“The tools used by Aéroports de Paris controllers run on four different operating systems, that are all between 10 and 20 years old,” a representative of the Paris air traffic controllers’ union explained to Vice News. There are some Unix systems, and some fresh and new computers running Windows XP. Orly, the city’s smaller airport, handles flights within France and within Europe, but Roissy-Charles De Gaulle, one of the busiest airports on the planet, uses the same systems.

When there are so few computers out there still running these operating systems, there aren’t as many people around capable of troubleshooting and maintenance. There are three technicians in all of Paris for DECOR, the program that malfunctioned, and one of them is getting ready to retire. Windows 3.1 is not a hot topic in French IT training, as far as I know.

Planes trying to land at Orly were redirected to other airports, and everything ended happily here. Just try not to think about how many important systems run on ancient software that no one remembers how to troubleshoot.

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Windows 3.1 Is Still Alive, And It Just Killed a French Airport [Vice News]

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