A Nouvelair Airbus A320-200, performing flight from Djerba (Tunisia) to Paris Charles de Gaulle (France), reported IRS failure.

• Aircraft was climbing out of Djerba’s runway 27 when the crew stopped the climb at 8,000 feet advising of problems with their Inertial Reference Systems (IRS).
• The aircraft returned to Djerba for a safe landing on runway 27 about 15 minutes after departure.
• A replacement Airbus A320-200 registration TS-INR reached Paris with a delay of 4:15 hours.