An Easyjet Airbus A319-100, registration HB-JYK performing flight U2-1110 from Thessaloniki (Greece) to Basel/Mulhouse (Switzerland/France) with 154 people on board, was climbing out of Thessaloniki's runway 34 when the crew stopped the climb at FL100 reporting smoke in the cockpit and returned to Thessaloniki for a safe landing on runway 16 about 14 minutes after departure and taxied to the apron reporting the smoke had subsided while working the checklists. There were no injuries, emergency services did not need to intervene.
A short circuit was identified as cause of the smoke in the cockpit.
The airline reported a technical problem as cause of the return. A replacement aircraft is being dispatched to Thessaloniki.
On Jun 7th 2017 Switzerland's SUST reported the occurrence had been rated a serious incident and is being investigated by the SUST. At FL100 the crew requested to return to Thessaloniki reporting fumes in cockpit and cabin.