Accession Number : AD0698347

Title :   SPINNING-WIRE DENSIMETER DEVELOPMENT.

Descriptive Note : Final rept. 17 Oct 66-31 Aug 69,

Corporate Author : HONEYWELL INC ST PAUL MINN RESEARCH DEPT

Personal Author(s) : Koehler,Lyle E. ; Rohrbough,Stephen F.

Report Date : NOV 1969

Pagination or Media Count : 110

Abstract : Analytical studies indicate that the Spinning-Wire Densimeter approach to density measurement is viable. The sensor consists of a wire drag element with a solar-sensor-modulated miniature 1680-MHz transmitter located at its center. A rotation rate of approximately 1000 rad/sec is given to the sensor as it nears the rocket's apogee. It is then ejected and allowed to free fall. Its spindown rate is a measure of atmospheric density. Error analyses show that, with a receiver output signal-to-noise ratio of 60 db, the maximum density error with the present sensor design is about 30 percent for a 450,000-foot apogee and about 3 percent with a 400,000-foot apogee. Gyroscopic righting effects, electric field and plasma sheath effects do not produce significant torques on the sensor. However, an additional error results if no correction is made for dimensional variations. (Author)

Descriptors :   (*STRATOSPHERE, DENSITY), (*ATMOSPHERIC SOUNDING, METEOROLOGICAL INSTRUMENTS), (*DENSIMETERS, DESIGN), DRAG, DETECTORS, EQUATIONS OF MOTION, STRESSES, SIGNAL-TO-NOISE RATIO, TELEMETER SYSTEMS, ULTRAHIGH FREQUENCY, FREQUENCY MODULATION, TEST METHODS

Subject Categories : Meteorology
      Test Facilities, Equipment and Methods

Distribution Statement : APPROVED FOR PUBLIC RELEASE