As most frequent fliers know, turbulence can be both a nuisance and a danger. Scientists aboard a research aircraft owned by the National Science Foundation tested a new detector that could provide a first defense against these dangerous patches of swirling wind. The Doppler lidar sensor sends laser beams several miles ahead of the plane. When the beams hit airborne particles such as dust or aerosols, they reflect to the plane. During the experiments, which occurred March 23 and April 10, scientists sought out turbulent areas over the Rocky Mountains to test the technology. Once engineers perfect the sensor, it will characterize the turbulent air motions ahead in time for pilots to warn passengers to fasten their seat belts.