Laser scanner could help pilots avoid atmospheric turbulence

Pilots might one day be able to navigate around turbulence using a laser system undergoing trials in Germany.


Researchers from a cross-European project have developed a LIDAR system that can measure the fluctuating density in an area of the atmosphere in order to indicate whether it contains turbulence, even if the sky appears otherwise clear.

The scientists from the DELICAT (Demonstration of LIDAR based Clear Air Turbulence detection) project are testing the technology at the German Aerospace Centre (DLR) in the hope it might one day lead to an integrated system for commercial aircraft.

The atmosphere can contain layers of air that move against each other horizontally at different speed and the difference between them is know as wind shear. Particularly strong wind shear can cause breaks in the air currents that create vortices.

When an aircraft enters one of these vortices, it alters the angle of the airflow over the wings and causes a sudden change in the plane’s altitude. Because these vortices are invisible they are virtually impossible for the pilot to avoid or prepare for.


The new LIDAR system emits short-wave ultraviolet laser radiation along the direction of flight and determines the density of the upcoming air based on how the reflected light is scattered by oxygen and nitrogen molecules.

The researchers are using a modified Cessna Citation passenger plane operated by the Dutch National Aerospace Laboratory (NLR) to test the system and collect data on the formation mechanisms of turbulence.

They hope this will enable them to develop a commercial system that could allow pilots to warn passengers of turbulence before it happens, giving them time to return to their seats and fasten their seat belts, or avoid the affected region of sky altogether.