DESIGN AND DEVELOPMENT OF AN ISOTOPIC ALTIMETER SETTING INDICATOR. VOLUME II. APPENDIXES.

Abstract

Design and development of an altimeter setting indicator system based on use of a radioactive alpha particle emitter as the primary sensing mechanism is described. Because the isotope measures density, a controlled temperature enclosure is utilized to provide an output proportional to pressure. The system uses a computer controlled closed loop servo to maintain the source at the 'constant range' position with respect to the detector. A shaft encoder maintains continuous knowledge of the actual source-detector distance, by which the pressure is deduced from a calibration curve. The altimeter setting indicator is calculated by the computer and displayed digitally. In its present form the system does not meet the design objective accuracy of plus or minus 0.005 inches of mercury. It is believed, however, that when temperature instabilities are corrected this objective will be achieved. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jun 01, 1969
Accession Number
AD0696586

Entities

People

  • B. Sellers
  • P. Morel

Tags

DTIC Thesaurus Topics

  • Accuracy
  • Alpha Particles
  • Altimeters
  • Calibration
  • Computers
  • Detectors
  • Flight Instruments
  • Indicators
  • Instability
  • Instrumentation
  • Measurement
  • Measuring Instruments
  • Particles

Fields of Study

  • Physics

Readers

  • Geodesy
  • Robotics and Automation.
  • Solar Physics