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Prclirninary wind tunnel tcs1.5 have bccn madc in ISAS in order to study the characteristics of the parachutcs at transonic and supersonic Mach number regions. A device has bccn madc to eject a model parachute into a wind tunnel flow and to measure the drag force acting on it. Some experimental studies on parachute deployment have been carried out by using the device set on the inside wall of transonic and supersonic wind tunnels having t g t sections of 60cm square in ISAS with the flow conditions of Mach number from 0.8 to 3.0 and Reynords numbcr from 2.2 to 2.9*107/m. Parachute models employed in this study have been made of practical parachutc materials. Thcir shapcs arc similar to conical and equiflo types. The relations between the Mach number and the drag, parachutc diameter, oscillating angle arc obtained, and thcsc comparative acrodynamic characteristics were discussed, including the effect of forebody wake. Some typical phenomena such as "breathing" at supersonic spccd are obscrved and their frequencies are also measured. Furthermore, some qualitative invesligation was made on thcsc "breathing" phenomena.

In present ballooning missions, as payloads increasingly become heavier and more sophisticated, much higher reliability is required in the balloon itself and in the launch operational technique. Hence, ISAS (the Institute of Space and Astronautical Science) has developed a balloon made of relatively thick films reinforced with high-strength fiber fabric (ref. 1 to 3). In order to verify structural properties and manufacturing quality, partial strength tests together with a trial production of small scale balloons have been car ied 5 . out. In 1990, a sub-scale B5 (5,000 m In volume) size balloon was produced, and a full inflation test on the ground prior to a flight experiment was implemented on account of demonstrating the basic capability of the fiber reinforced balloon. This paper describes research and development of the proposed balloon associated with selection and verification study of the high-strength fiber reinforced film.