DETERMINING ALTITUDE OF AN AIRCRAFT DURING FLIGHT BASED ON VORTEX SHEDDING

Apparatus and associated methods relate to determining altitude of an aircraft during flight based on properties of vortex shedding. A vortex-shedding projection (14) is projected into the airstream adjacent to the exterior surface of the aircraft so as to cause vortex-shedding turbulence (36) of the airstream. One or more downstream sound-pressure detectors (16A - 16G), which are attached to the exterior surface of the aircraft downstream from the vortex-shedding projection, detect(s) a vortex-shedding frequency f of the vortex-shedding turbulence caused by the vortex-shedding projection. A processor (18) determines the altitude of the aircraft based, at least in part, on the vortex-shedding frequency f of the vortex-shedding turbulence as detected by the one or more downstream sound-pressure detectors.