The AFGL-instrumented MC-130E aircraft made several 8-min particle-sampling passes off the San Francisco coast on 10 July 1978 at levels from 100 to 1000 ft altitude. Spectrometers capable of recfording particles from 2 to 6400 micrometers were used, but in the existing cloudless conditions only particles between 2 and 30 micrometers were detected. These were recorded by the PMS axial scattering spectrometer probe.

On 22 March 1979, an instrumented MC-130E for cloud physics measurements by AFGL made a series of 8-min sampling passes at altitudes ranging from 100 to 1000 ft above the ocean surface off the coast of Washington. The flight profile was similar to that flown by the same aircraft on 10 July 1978 off the coast of California (AFGL-TR-79-0013). Winds were light, and the visibility generally was 7 miles or greater. Varying numbers of particles were detected in the 2 to 22 micrometer range at all levels. The number of particules was fairly constant with altitude; liquid water content (LWC) was about 0.001 g/cu m at all levels. This was in contrast to the 10 July 1978 flight, where LWC varied much more, both with height and location. The differences between the two flights are attributed to the lower windspeeds and the resultant fewer whitecaps observed on this second flight. (Author).