METHOD FOR DETERMINATION OF PITOT PROBE AERODYNAMIC ERRORS IN FLIGHT TESTS OF FLYING VEHICLE

摘要

FIELD: instrumentation.;SUBSTANCE: invention refers to instrumentation, specifically to flight altitude-velocity parametre (AVP) gauges and can be used in flight tests of flying machines as related to determination and assessment of AVP measurement errors. The method includes operations for: measurement of air parametres, angle parametres of airplane spatial position, flight trajectory parametres; executing test modes of flying vehicle (FV) as horizontal fields with preset height values at subsonic velocity in operation range; determination of atmospheric pressure change when flight geometrical height is changed; determination of actual pressure at flight height from equation of atmosphere statics, atmosphere conditions at airfield level or flight probing mode and flight relative height. Further following operations are performed: determination of dependence of pitot probe (PP) static pressure sensing error from Mach number (M) and incidence angle in low-level flight modes; determination of dependence of PP static pressure sensing error in full operation range of M variations; determination of PP full pressure sensing error in M number variations operation range by values of full pressure perceived by PP, calculated (actual) M number values and static pressure values in each horizontal mode of flight at preset heights with opposite courses with various fixed velocity (M number) values in operation range of heights and velocities. For this purpose dependence of full pressure sensing error from M number (in low-level flight M number variations range) is determined at low level from measurement data for full pressure, static pressure actual values and M number. At high altitudes, following parametres are determined: actual values of static pressure and temperature in probing horizontal modes of flight with opposite courses at low speed (M number) from measured values of full pressure, braking temperature and trajectory parametres with excluding full pressure sensing error with respect to dependence obtained at low level. To determine sensing error for full and static pressure in full operation range of FV altitudes and velocities in each mode following parametres are determined: air velocity - from trajectory measurements, actual values of static pressure and temperature - by calculating from probing mode.;EFFECT: improving accuracy of aerodynamic errors determination for pitot probes (PP).;2 dwg