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~ I I I J I During operational periods various information was entered manually into our computer so that comments and calculations could be recorded quickly. The information obtained included: . (1) storm position relative to the radar site (2) cloud height (3) maximum intensity (4) height of the 45 dBZ level (5) 45 dBZ height above or below a computed hail .threshold (6) cloud height (7) cloud height above or below the tropopause Data were also logged on separate forms during program operations. Acetate overlays of storm location were hand-drawn at 20-minute intervals,for hail suppression and at 20 to 30 minute intervals for rainfall augmentation. On the overlays were drawn all radar echoes, the primary storm intensity centers and the location of all aircraft. These overlays were later photocopied and shaded in various colors for permanent reference purposes and for post-operational analyses. Storm activity and aircraft positions were also documented by an 5 mm time- . lapse camera system mounted atop a second PPI display nearby. I Drawn onto the radar PPI is the outline of the target area boundaries, target area counties, neighboring counties, state line and positions of many regional towns. Also, lines are drawn at each ten degrees of compass using the Garden City VOR as the primary aircraft navigational aid. Range marks have been put on those VOR radial lines so that a close approximation of distance and direction from the VOR is instantly available to the meteorologist during operations. D. AIRCRAFT SEEDING OPERATIONS Three cloud base seeding aircraft and one cloud-top aircraft were used in the 1959 operational period. The cloud base planes used were: (1) 3 single engine Piper Aircraft Comanches, PA24-250 (2) 1 twin-engine Piper Navajo, PA31-325 All three cloud base aircraft were equipped with Carley-type liquid fuel generators for cloud seeding, one mounted to each wing tip. Each generator holds approximately 6 gallons of a liquid solution of seeding agent and burn silver iodide at the rate of two grams per minute of operation, or approximately two gallons an hour. Each plane carries approximately 720 grams of silver iodide and is capable of a minimum continuous seeding time aloft of about 3 hours (using both generators, simultaneously>. The planes were flown on an as-needed basis during the season. These aircraft worked at cloud base in the preferred updraft areas of the clouds. The planes were based at the towns of Lakin, Johnson and Scott City The cloud top aircraft, based in Dodge City, was equipped with a specially built dry ice dispenser capable of carrying 200 pounds and releasing 5 pounds of dry ice per minute. About 200 additional pounds of dry ice could be carried aboard the plane as well, The aircraft normally attempted seeding at the -20 C level, but final altitude assignment depended upon FAA Air Traffic controllers. The plane made penetrations near cloud top releasing the dry ice into the newly growing clouds around parent storms or into incipient storm development along longer lines.