The report describes a study which was performed in order to examine the development and collapse of mixing layers with particular emphasis upon the latter using aircraft motion due to air turbulence as the primary measured quantity. Variations in this process which might be attributed to cloud cover, urbanization, wind patterns and other meteorological parameters were sought. Toward this end data were collected in several meteorological patterns and in one urban (Atlanta) and one rural (Gainesville, Florida) setting. Data were gathered by making vertical soundings with an instrumented aircraft and recording signals that would furnish measures of the mixing height and a function of turbulent energy levels therein. Thus altitude, temperature and lateral acceleration of the aircraft were sensed and recorded simultaneously. The RMS value of the aircraft lateral acceleration was also monitored and recorded, thereby serving as an atmospheric turbulence indicator. The results and conclusions are presented. (Author)