A constant-altitude balloon experiment at 48 kilometers

Abstract

A helium‐filled, zero‐pressure (internal and external pressures equal), polyethelene balloon, 28.7 million cubic feet in volume (the largest to date), was launched on September 11, 1968, from White Sands Missile Range (WSMR), New Mexico, to study the atmospheric tides that rocket soundings have indicated exist in the atmospheric region from 40 to 60 km. The balloon served as a constant‐level stable support for a scientific payload consisting of six instruments for the measurement of temperature, pressure, density, and related ozone and water vapor concentrations near 48 km. Radar position‐time data served to determine the wind velocity. The balloon reached a record altitude of 48.5 km and then followed a predicted trajectory extending from WSMR to Twenty‐Nine Palms, California. Seventeen hours of stratospheric meteorological data were obtained, of which four hours were obtained in the 48‐km altitude region. This paper describes the various aspects of the balloon system and its flight and lists the significant results obtained; it is intended to serve as a reference for subsequent papers related to a detailed analysis of the various records.

Measurements from a zero-pressure balloon in the stratopause (48 km)

“…The modification primarily involved reducing the pressure range and improving the resolution of the gage. As described by Ballard et al [1969], the thermoconductivity gage timeshared the data transmitter so that pressure data were telemetered for one continuous minute out of every five m:nutes throughout the flight. The gage performance was excellent as evaluated by several standards.…”

“…The experiment design called for a 24-hour float in the stratopause region near 48 km. Ballard et al [1969] have described the complete experiment plan, instrumentation, and balloon performance; and Randhawa [1969] has reported on the results from the ozone measurements made during the balloon flight. This discussion will center on pressure, temperature, Copyright ¸ 1970 by the American Geophysical Union.…”