Molecular Air Data Clear Air Turbulence Sensor: MADCAT

Clear air turbulence (CAT), often referred to as "air pockets," is attributed to Kelvin-Helmholtz instabilities at altitudes usually above 18,000ft, often without visual cues (clouds, etc.), making it difficult to avoid. The vortices produced when atmospheric waves "break" can have diameters of 900-1200ft and tangential velocities of 70-85 ft/sec. CAT is dangerous to aircraft, recently demonstrated by United flight 967 from Washington-Dulles to Los Angeles on July 21, 2010, which encountered severe turbulence and landed in Denver with over 30 injured passengers, 21 requiring a hospital visit. Many other turbulence incidents have caused injuries or deaths to passengers and crew. Another recently-highlighted hazard is the inadequacy of current airspeed sensors on commercial aircraft. Federal investigators have reported that on at least a dozen recent flights by U.S. jetliners, malfunctioning equipment made it impossible for pilots to know how fast they were flying. A similar issue is believed to have played a role in the June 2009 crash of Air France 447 that killed all 228 people aboard. Michigan Aerospace Corporation (MAC) proposes the Molecular Air Data and Clear Air Turbulence (MADCAT) system which will be capable of providing not only a look-ahead capability to predict clear air turbulence but also a full air data solution (airspeed, angle of attack, angle of sideslip, pressure and temperature). The technology has already been demonstrated in-flight, confirming its ability to measure these air-data parameters. In addition, ground units based upon the same core technology have demonstrated the ability to detect atmospheric turbulence. MAC's direct-detection UV LIDAR technology uses molecular backscatter and does not require airborne particles and/or vapor to be suspended in the air, as other proposed solutions based on radar and LIDAR do. This Phase 2 project will result in a laboratory test model of MADCAT and a plan for subsequent airborne testing.