초록 ▼

Static pressure sensing and free airstream temperature sensing is obviated in a method for determining aircraft velocity relative to an airmass by utilizing a static pressure and temperature component present in pressure variations sensed by a total pressure sensor located on a rotating arm mounted

Static pressure sensing and free airstream temperature sensing is obviated in a method for determining aircraft velocity relative to an airmass by utilizing a static pressure and temperature component present in pressure variations sensed by a total pressure sensor located on a rotating arm mounted on the fuselage of an aircraft. A harmonic analysis of a quasi-sinusoidal total pressure variation includes a determination of steady state and both first and second harmonic components. These harmonic components are used to determine the static pressure, the free airstream temperature and the aircraft airspeed without separately sensing these parameters.

대표청구항 ▼

A method of providing an airspeed signal indicative of a velocity of an aircraft relative to an air mass surrounding the aircraft relative to a frame of reference fixed in the aircraft, the aircraft having at least one sensor for providing a sensed pressure signal as a sensed air data parameter that

A method of providing an airspeed signal indicative of a velocity of an aircraft relative to an air mass surrounding the aircraft relative to a frame of reference fixed in the aircraft, the aircraft having at least one sensor for providing a sensed pressure signal as a sensed air data parameter that is indicative of pressure at a rotating member and a sensed periodic reference signal indicative of the rotating member periodically passing a reference position relative to the frame of reference, comprising the steps of: selectively sampling the magnitude of the sensed pressure signal according to the position of the rotating member for each of a plurality of subrevolution intervals, and providing sampled pressure signals having magnitudes indicative of said magnitude of the sensed pressure signal during each of said plurality of subrevolution intervals, as determined with respect to the sensed periodic reference signal; providing, in response to said sampled pressure signals, multiple order harmonic component pressure signals having magnitudes indicative of multiple order harmonic component representations of the pressure at the rotating member; and utilizing the multiple order harmonic component pressure signals for determining aircraft velocity, for providing the airspeed signal having a magnitude indicative thereof thereby using only one sensed air data parameter in said method of providing said airspeed signal.