The present study aims to give some data on the evolution of fatigue during shorthaul flights and to propose some solutions to prevent fatigue. The method is mainly based on in-flight evaluation and observations the roster. This study was carried out on eight rosters covering 67 short-haul flights. The legs were scheduled either only during the morning or in the afternoon or included both morning and afternoon flights. Results show that sleep before morning flights is significantly shorter than sleep taken before afternoon flights. The sleep reductions associated with morning flights lead to a higher level of fatigue and workload compared to the afternoon flights. The results are discussed in relation with flight safety and some recommendations are addressed regarding the scheduling of rosters.