Air Corsica has temporarily taken five of its seven ATR 72-600 aircraft out of service after multiple reports of strange odors, especially in the cockpit areas. The cause of these odors is still unknown. To keep flights running to the island of Corsica, the company is using aircraft it has rented, while investigations into the issue will take several weeks to complete. The withdrawal means that most of Air Corsica's turboprop fleet is currently unavailable. In a statement on September 23, the company confirmed the preventive removal of the five ATR 72-600 aircraft due to "repeated reports of unusual odors, particularly in the cockpit." Pierre Muracciole, the chairman of the board, told AFP that the odors could "resemble oil fumes," which might be uncomfortable for the flight crew. To investigate the issue, Air Corsica is working with the aircraft manufacturer ATR, the engine manufacturer Pratt & Whitney Canada, and the equipment supplier Liebherr. These investigations are ongoing, particularly at the ATR workshops in Toulouse, France. Air Corsica has warned that it will not announce a return-to-service date for the aircraft until all checks are completed and the required technical conditions are validated. No widespread defect has been found in the ATR aircraft. According to a spokesperson cited by AFP on September 28, the decision to ground the planes was made to give the teams time to understand the phenomenon and determine any necessary corrective actions. The aircraft manufacturer emphasized that the cause of the odors has not been identified and that there is no evidence to suggest the issue affects all ATR aircraft. At this stage, no measures affecting the entire manufacturer's fleet have been deemed necessary. The situation is challenging for Air Corsica, as five grounded aircraft represent more than 70% of its ATR fleet. These 72-seat aircraft are typically used for short-haul flights, such as between Corsica and Nice, Corsica and Lyon, or Marseille and Calvi. The affected aircraft were delivered between November 2022 and August 2024. To maintain its flight schedule, Air Corsica has arranged for charter aircraft and is using some of its Airbus planes. The company announced on September 9 that it would use an A319 from Amelia, an ATR 72 from Chalair, and an A350 from Air Caraïbes on September 12 and 13. This large aircraft was intended to free up A320s from Air Corsica so they could replace the grounded ATRs. However, travelers still face some uncertainty, as flight schedules and the specific aircraft assigned to each flight are yet to be confirmed before departure. The situation also comes with financial implications. A source within Air Corsica told AFP that technical conclusions from the investigations would help determine who would cover the costs of the rented aircraft. For now, neither the cause of the odors nor the timeline for the ATRs' full return to service is known.