TRANSOCEANIC, POLAR PATROL BALLOONS AND FUTURE-PROSPECTS

The long duration balloon system called ''Boomerang Balloons'' and ''Cycling Balloons'' have been successfully applied to scientific observations in Japan which utilize the change of wind direction at different altitudes. Trans-oceanic flights were also conducted between Japan and China during 1986 to 1988. A recent achievement is to circulate the balloon over the Antarctica in the summer season. Such ''Polar Patrol Balloons'' have been conducted by the National Institute of Polar Research in collaboration with ISAS. The test flight succeeded in achieving a duration of more than 3 weeks over Antarctica. Other trans-oceanic flight systems are now under investigation utilizing the satellite link over the Pacific-Ocean. Combining this system with the concept of ''Bomerang balloons'', we are now studying the possibility of long duration flights of more than a week, with the recovery of the payloads on the east coast of Japan after the flights.