Instantaneous,predictable balloon system descent from high altitude

The 13 inch diameter helium valve has long been the only method for initiating and controlling balloon system descent. As greater altitudes have become standard, the 13 inch valves have become less and less effective. It takes as long as a half hour or more to effect a noticeable descent, even with two or three valves, at altitudes in excess of 120,000 ft. The project that prompted this study called for a descent rate of >1000 ft/min from 131,000 ft to 60,000 ft. The method by which this was accomplished is presented along with recommendations for future work to provide closer control of rapid descents such as this.