Engineers at NASA’s Langley Research Center in Hampton, Va., used lasers inside the 14- by 22-Foot Subsonic Tunnel to map how air flows over a Boeing Blended Wing Body (BWB) model – a greener, quieter airplane design under development. The name for the technique is called particle image velocimetry. If you look closely you can see the light bouncing off tracer particles. Cameras record the movement of those particles as the laser light pulses across the model. This allows researchers to accurately measure the flow over the model once the images are processed. A smoother flow over the wing means less fuel will be needed to power the aircraft.