Flight velocity vector measuring system in wide velocity region using truncated pyramid-shape probe

Abstract

A flight velocity vector measuring system in a wide velocity region in which an attack angle pressure coefficient C&agr; of air current, a sideslip angle pressure coefficient C&bgr; and an air current angle pressure coefficient C&ggr; are obtained from five pressure information detected by a square truncated pyramid-shape probe. The aforementioned pressure coefficients, pressure calibration coefficients with respect to a Mach number M, an attack angle &agr; and a sideslip angle &bgr; every velocity region obtained by dividing the wide velocity region into a plurality of regions stored in advance in the calculation processor, and a Mach number M, an attack angle &agr; and a sideslip angle &bgr; of unknown quantity constitute a calculation processing expression comprising a polynomial approximation to call the pressure calibration coefficients in the velocity region, and flight velocity vectors (M, &agr;, &bgr;) are calculated by the polynomial approximation.