Determining altitude of an aircraft during flight based on vortex shedding

A method for equipping an aircraft with an altitude determination system for operation during flight, the method comprising:

• projecting a vortex-shedding projection into an airstream adjacent to an exterior surface of the aircraft, the vortex-shedding projection configured to cause vortex-shedding turbulence in the airstream adjacent to the exterior surface of the aircraft;
• attaching one or more sound-pressure detectors at locations downstream, during flight, of the vortex-shedding projection, each of the one or more sound-pressure detectors configured to detect a vortex-shedding frequency f of the vortex-shedding turbulence cause by the vortex-shedding projection during flight,
• electrically coupling a processor to the one or more sound-pressure detectors,
• configuring the processor to determine altitude of the aircraft during flight based, at least in part on the vortex-shedding frequency f detected by the one or more sound-pressure detectors.

A method for determining altitude of an aircraft during flight, the method comprising:

• causing, via a vortex-shedding projection, vortex-shedding turbulence;
• detecting, by one or more sound-pressure detectors located downstream from the vortex-shedding projection, the vortex-shedding turbulence caused by the vortex shedding projection;
• determining, via a processor, a vortex-shedding frequency f of the vortex-shedding turbulence caused by the vortex-shedding projection;
• and
• determining, via the processor, the altitude of the aircraft, based, at least in part, on the vortex-shedding frequency f determined.