The aircraft had departed Lisbon at just after 6pm, an hour and a half behind schedule.
The plane was only half hour from landing in Luxembourg when the incident happened, but the pilot opted to land at Charles de Gaulle airport in Paris as a safety precaution.
According to reports, the pilot kept passengers informed of what was happening, but “initially said the diversion was due to a technical problem with the onboard computer” newspaper Diário de Notícias said.
A replacement aircraft was dispatched to collect the affected passengers and complete the flight to Luxembourg, and make the return leg from Luxembourg back to Lisbon.