ONERA activities on high-lift devices for transport aircraft

High-lift systems have to provide adequate low speed performance in terms of takeoff and landing lengths, approach speed, climb rate and community noise. Even if the performance of these systems has been continuously improved during the years, there are still some possibilities for further improvements. ONERA has been involved for a long time in research on high-lift systems for transport aircraft. This research has provided valuable results in the following areas: ● The knowledge of the dominant flow processes involved for 2D and 3D geometries. In particular the stall mechanism, Reynolds and Mach number effects as well as sweep effects have been studied by performing detailed experiments. ● The development of 2D analysis and design codes which have been extensively calibrated with experimental data and are used with confidence for practical applications. ● The design and testing of various high-lift systems which provide manufacturers with data for their own designs. The paper summarises these activities and presents some typical results. Future trends for research on high-lift systems at ONERA are also given.