routine flight to 13S. high-altitude transit to 13S, followed by in-situ sampling on the way back that included three samples of the cloudy boundary layer, at 13S, ~8.5-7.5S, and 3.5S. boundary layer was mildly polluted. aerosol layer at southern end reached 19.5 kft. flight included speed runs for the cloud probes (the 2 CDP probes in particular).