Patent ID: 7605369
Filing Date: 2009-10-20
Classification: G01C,G01N,G08G

Abstract:
1. A method of permitting dispatch of pilot-operated, enhanced vision system (EVS)-equipped transport aircraft to a destination and, upon approach of the aircraft to the destination, permitting operations below conventional operating minima for the EVS-equipped transport aircraft and destination equipage, the EVS including EVS infrared sensors that operate at wavelengths and are characterized by range performance, and the destination characterized by contrast within a background scene in a background scene waveband and intensity of aircraft runway lights in a runway light waveband, comprising: using a ground-based infrared visibility measurement system to provide EVS range performance information that includes first and second infrared visibility levels at wavelengths of the EVS infrared sensors with which the transport aircraft is equipped, the first infrared visibility level corresponding to the contrast within the background scene in the background scene waveband and the second infrared visibility level corresponding to the intensity of the aircraft runway lights in the runway light waveband; determining atmospheric extinction coefficients at the background scene waveband and the runway light waveband; and predicting for the EVS infrared sensors an EVS range of distances at which the background scene and aircraft runway lights at the destination are discernible by the EVS infrared sensors, the EVS range of distances determined by processing of the EVS range performance information and the atmospheric extinction coefficients at the background scene and runway light wavebands, thereby to provide a predicted EVS range of distances that preclude or minimize a chance of a missed-approach maneuver by the transport aircraft dispatched to or approaching the destination.