BAE Systems is exhibiting its new Laser Air Speed Sensing Instrument (LASSI) on its display here at the Farnborough Airshow (in Outdoor Exhibit 11). The device, which was created by British scientists in Chelmsford, UK, is designed to measure velocity in high altitude aircraft. According to BAE, LASSI can improve performance and fuel efficiency.
Airspeed is generally determined by using pitot tubes located on the outside of the aircraft that sense differences in air pressure, which is directly related to speed. However, this new device bounces ultraviolet laser light off air molecules and measures the change in color of reflections caused by the Doppler effect.
Dr. Leslie Laycock, executive scientist at BAE Systems, explained, “Conventional air data sensors which protrude from the sides of aircraft must be carefully located to work properly and are inaccurate at low airspeeds. LASSI can be located completely inside the aircraft and is accurate at low airspeeds. It can even measure negative air velocities. These features should ensure that the equipment is robust against damage, require less maintenance and be easier to operate at lower airspeeds.”
LASSI has been tested in a low-speed wind tunnel and on ground vehicles. BAE Systems predicts that the component technology could be developed on a smaller scale and be in use within the next five years.