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Harold N. Ballard

Abstract

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Harold N. Ballard

Abstract

Careful consideration of the heat transfer equations for a rocket-borne stratospheric temperature sensor in the form of a spherical bead thermistor coupled with an experimental analysis of the physical, thermodynamic and electrical characteristics of the rocketsonde, indicated that the corrections to the observed thermistor temperatures could be substantially reduced through development of a new rocketsonde. Redesign of the rocketsonde temperature sensor reduced the theoretical temperature correction at 65 km from a value of 36C for the Delta-I temperature sensing instrument to approximately 6C for the new design. Temperature data obtained with the new stratospheric temperature sonde STS-1 showed that, after instrument expulsion at 74 km and at rocket nose-cone temperature near 100C, the thermistor temperatures at and below 60 km were, without correction, in close agreement with those predicted by the U. S. 1962 Standard Atmosphere.

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Harold N. Ballard
and
Roberto Rubio

Abstract

Atmospheric temperature sensing elements studied in this report are presently being used at Meteorological Rocket Network stations. The steady-state solution to the heat transfer equation is given for a thermistor which is attached to an instrument package by some type of mounting configuration, the instrument in turn being supported by a parachute. The solution includes the effects of aerodynamic heating of the thermistor and thermistor mount; conduction along the thermistor lead wires, as well as heat transfer by convection from them; and solar irradiation of the thermistor and its leads. The solution gives expressions for the dissipation factors and thermal time constants of the sensing elements which, in turn, permit the calculation of corrections to the observed spherical bead thermistor temperatures of the rocketborne Stratospheric Temperature Sonde (STS) and Arcasonde instruments, as well as corrections to the observed cylindrical rod thermistor temperatures of the balloon-borne AN/AMT-4 radiosonde. Temperature profiles obtained with the STS and Arcasonde instruments are presented. The computer program, in Fortran IV language, developed to calculate the temperature corrections is outlined.

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Harold N. Ballard
,
Miguel Izquierdo
,
Jack Smith
, and
John Whitacre

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Harold N. Ballard
,
Miguel Izquierdo
,
Jack Smith
, and
John Whitacre

Abstract

Theoretical and experimental studies have led to the development and fabrication of a rocketborne beta-ray densitometer for the direct determination of atmospheric density in the 30–65 km atmospheric interval. Comparison of atmospheric density profiles determined by the Betasonde densitometer with temperature-derived atmospheric density profiles showed excellent agreement to 35 km. Above 35 km, however, the two profiles gradually, diverged until at 50 km the Betasonde-determined density was 35–40%. greater than the temperature-derived density. This paper discusses the results of the cosmic ray count determination in the 0–50 km region with a cosmic ray detector, identical in configuration and sensitivity to the Betasonde, which served as a part of the instrument package on a high-altitude balloon flight from White Sands Missile Range, to 50 km on 22 September 1969. These results indicate that the differences in the comparison atmospheric density values can be attributed to cosmic rays which are detected by the Betasonde.

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Harold N. Ballard
,
Norman J. Beyers
,
Bruce T. Miers
,
Migul Izquierdo
, and
John Weitacre

Abstract

A balloon, the second In a series of high-altitude balloon flights, was launched to a record altitude of 50 km from White Sands Missile Range, N.M., on 22 September 1969. The 8.7 × 105 cubic meter, helium-filled, zero-pressure, polyethelene balloon served as a constant-level stable support for an instrument payload consisting of bead thermistor atmospheric and balloon-skin temperature sensors, thermal conductivity pressure gage, a forward-scattering beta-ray atmospheric density gage, chemiluminescent ozonesondes, a Geiger tube cosmic ray detector, and an accelerometer for the determination of the vertical component of balloon acceleration. Radar position-time data served to determine the wind velocity. Seven hours and 40 minutes of data were obtained from the various instruments at a near-constant altitude of 49 km (± 1 km). This paper discusses specifically the variations in the observed balloon trajectory, the supporting rocketsonde-determined winds, and the balloon-borne temperature sensor values as related to the existence of a diurnal atmospheric tide near 50 km. It also presents the related data obtained from the other instruments comprising the payload.

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