How Windows 3.1 Brought Down an Airport

At Paris-Orly airport, Air Traffic Controllers use a system called DECOR to “communicate weather conditions to pilots.”

The system runs on Windows 3.1 and it crashed last Saturday.

In doing so, it prevented air traffic controllers from giving pilots other critical information—like the “runway visual range” (RVR), or the distance at which a pilot can expect to be able to see down the runway.

Windows 3.1 was released in 1992. It was still Windows in the sense that it was a DOS-based overlay that gave you various windows on your computer screen. It’s the operating system that was made obsolete by Windows 95.

Other airport systems run on UNIX and Windows XP. Tech support for the Windows 3.1 DECOR system is extremely scarce. Apparently there are only 3 specialists who can work on the system, and one is nearing retirement.

A spokesperson for the Ministry of Transport says the system will be modernized in 2017 though others speculate it could be “2019 at the earliest, perhaps even in 2021.”

About Gary Leff

Gary Leff is one of the foremost experts in the field of miles, points, and frequent business travel - a topic he has covered since 2002. Co-founder of frequent flyer community, emcee of the Freddie Awards, and named one of the "World's Top Travel Experts" by Conde' Nast Traveler (2010-Present) Gary has been a guest on most major news media, profiled in several top print publications, and published broadly on the topic of consumer loyalty. More About Gary »

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  1. You know running 3.1 might not be such a bad thing if it’s not connected to a virus source, does what is needed and is run on newer computers. It should be blazing fast on a modern computer. Besides any operating system can fail.

  2. ” was made obsolete by Windows 95.”

    No…. It was made obsolete by Windows XP. Win95 was a much panned POS much like Vista.

  3. @curt
    Windows 95 sparked the widespread use of the home personal computer and modernized operating systems and is the true basis of current Windows os (ignoring the tiles/metro interface). It may have been buggy or for whatever reason you call it a pos but its importance in history cannot be ignored and is what vaulted Microsoft to the top of tech at the end of the millennium.

  4. @curt

    I think you’re missing a few steps. In between Windows 3.1 and XP were Windows NT4, 95, 98, 98SE, 2000, and ME. Of those, 98SE and 2000 were fairly highly regarded, with ME being the “much panned POS” you’re referring to. 95/98 were the standard for a long time before XP was released.

  5. What DaninMCI wrote was the first thing I thought after reading your post. I guess they still use Windows 3.11 for security purposes, since virus and spywares nowadays are made for better OS.

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