Development of a Balloon to Reach 60,000 Feet at 2,000 Feet Per Minute

摘要

A theoretical study was made based on previous experience with ML-399, ML-541 and ML-566 balloons, for the design of a balloon to reach 60,000 feet at 2,000 feet per minute by day and by night. The compounds available were reviewed and two were selected, one suitable for the high modulus gas carrying balloon and the other for the streamlined tail, if this proved necessary. Thick-walled balloons were manufactured from the compound selected and single cell spherical and elliptical balloons were evaluated in flight. As a result of the performance obtained, subsequent flights were restricted to streamlined balloons. Spherical head and elliptical head assemblies with streamlined tails were fabricated and flown. The desired wall thickness was always obtained by placing one or two balloons inside another balloon. An assembly using an intermediate balloon with excellent shape characteristics but low bursting altitude was also evaluated. A double spherical head balloon with a streamlined tail was adopted as the final design. (Author)