A virus apparently attacked an Air Canada Jazz flight-planning computer at an operations centre in Halifax that provides essential information on fueling, weather, and other variables. Without the computer’s flight information releases, aircraft cannot take off. 

The problem began at about 3 p.m. EST in a flight-planning computer that provides essential information on fuelling, weather and other variables for the roughly 700 flights that Jazz operates daily between 72 centres, spokesman Dennis Erickson said from Calgary.

The problem affected only Air Canada’s regional operations.  Without the computer’s flight releases, aircraft could not take off, AC Spokesman Dennis Erickson said - adding that with the computer malfunctioning it was not clear even how many flights had been disrupted, He estimated that about 200 had been affected, some canceled and some delayed.