islands, and some elements of TG 7.3. Weather balloons were routinely re- leased twice daily to check winds aloft, with the releases increasing to eight per day prior to a shot. loons was 120,000 feet The maximum height attained by the bal- (36.60 km), and they averaged about 85,000 feet (25.91 km). Additional TG 7.3 meteorological support was supplied by weather re- _connaissance observations made every half-hour by P2v-6 aircraft while on their security patrols. The Curtiss and the Bairoko reported surface ob- servations hourly and radar wind soundings (rawinsondes) twice daily (Ref- erence 22, pp. M-1l through M-3). All units using balloons to obtain upper wind readings encountered equipment problems. The Curtiss relied on radiosondes as well as rawin- sondes to gather meteorological information. Rawinsonde tests determined the winds aloft patterns by radar observation of a balloon. Radiosonde, in contrast, used a balloon-mounted radio transmitter to automatically send meteorological information to a weather station. CTG 7.3 planned for the Curtiss to take hourly surface and twice daily radiosonde readings be- fore each shot and report at 2200 to CJUTF 7. Problems were encountered, however, with balloons freezing and bursting before reaching the tropopause. Also, because of the number of shot cancellations resulting from inauspicious weather, by the fifth shot (YANKEE) its supply of weather balloons. the Curtiss had depleted The consequence of balloons icing and bursting was that critical wind observations were sometimes terminated before reaching the maximum altitudes where wind patterns were significant (Reference 16, p. 90). Preshot planning forecasts issued at H-48 and H-36 hours consisted of wind forecasts for the shot site at 10,000-foot (3.05-km) increments from the surface to 90,000 feet (27.40 km). Following the selection of a spe- cific shot time, forecasts were issued at 24, 12, 8, and 4 hours before H-hour. These forecasts were more detailed: winds were forecast to the nearest 10° and to the knot for each 2,000-foot 114 (0.61l-km) increment from