>A third of all airline traffic is handled by systems that run SICStus Prolog
But are those systems responsible for all the I.T. problems that are plaguing the industry?[1] (I've been under the impression the issues were primarily with COBOL/mainframe systems, but wasn't aware Prolog was so widely used by airlines).
[1] https://www.google.com/search?hl=en&q=airline%20computer%20f...