DEVELOPMENT AND DESIGN CRITERIA FOR AN ULTRAVIOLET BACKSCATTER DENSITOMETER.
Abstract
The objective was to continue the development and determine the capability of an instrument to measure ambient air density from a hypersonic re-entry vehicle using available hardware and establish desigh criteria for the instrument. It was desirable to obtain an instrument to provide these data between altitudes of 300,000 and 100,000 feet. The concept of the air density instrument is to transmit a collimated beam of radiation through and beyond the shockwave, and have a telescope view a portion of this beam outside the shocklayer. Rayleigh and other experimenters previously showed a direct relationship existed between the quantity of scattered radiation and the number of air molecules. Efficient utilization of energy transformations within the instrument was the prime consideration during this contract. System tests to evaluate performance of the instrument were conducted in a constructed simulator and a radar anechoic chamber. Due to problems in test and evaluation in test facilities, the absolute capability of the instrument in terms of the maximum useful altitude could not be determined. However, from interpretation of data obtained from laboratory tests and supporting calculations, estimates were made which revealed that with selected components and 5-inch optics, a backscatter densitometer will be limited to altitudes below 150,000 feet. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1965
- Accession Number
- AD0477771
Entities
People
- Kenneth L. Wismer
- Richard F. Holtman
Organizations
- Boeing