Aircraft Wake Vortex Study and Characterization with 1.5 µm Fiber Doppler Lidar

For ten years now, Onera has been developing lidar tools for wake vortex detection and studies. Since 2003, new developments based on 1.5 µM fibered laser sources have been achieved in parallel with extensive research work on the laser sources themselves. Three innovative lidars have been developed and are presented in this paper: 1) A mini-lidar, based on a CW (continuous-wave) 2 W / 1.5 µM laser source, for aircraft model wake vortex characterization in a catapult facility. A self-triangulation technique allows the vortex core position to be found with 10 cm error, and the circulation error is 10 %. 2) A pulsed 1.5 µM lidar, based on a 50 µJ / 15 kHz MOPA (Master Oscillator Power Amplifier) source, for lateral wake vortex monitoring at airports. The range is 400 m, the core position error is about ± 2 m and the circulation error is about 10 %. 3) A pulsed 1.5 µM lidar, based on a 120 µJ / 12 kHz MOPA source, for onboard axial wake vortex detection. Ground based lidar tests at Orly airport have demonstrated wake vortex detection up to 1.2 km.