Measurement distortion in aircraft, space shuttle, and balloon observations of atmospheric density and temperature perturbation spectra

The results show that distortion is negligible in aircraft and space shuttle measurements of horizontal wave number spectra if the aircraft velocity is ~100 m/s or larger and the slant angle of the shuttle reentry path is ~0.5° or less. The distortion in balloon measurements of vertical wave number spectra is negligible provided the ascent velocity is ~3 m/s or larger and the horizontal wind speed is not more than about 10 times the balloon ascent velocity. This latter condition can be violated during some balloon flights when horizontal winds are strong. In those cirucmstances the measured spectrum will be larger in magnitude and have a shallower slope than the intrinsic vertical wave number spectrum. -from Authors