“Air traffic in the centre and north of Sweden was affected,” authority spokesman Erik Söderberg told AFP.
The failure grounded all take-offs for two hours, while landings were unaffected.
Although the system was repaired, further delays were expected, Söderberg said.
“The system was working again after about two hours of stoppage (…) but there will be some small delays during the afternoon,” he added.
Dozens of aircraft on both domestic and international routes were affected by the failure, according to Söderberg.
In all, some 20 of the country’s airports suffered delays, Arlanda international airport spokesman, Niclas Hårenstam said.