A Hybrid Computer Program to Obtain Stability Derivatives from Flight Test Data.

Abstract

A hybrid computer matching program for extraction of stability and control derivatives from flight test data was developed, initially for the X-24A Lifting Body. A hybrid computer reads flight test data into a digital computer, scales the data and outputs it to an analog computer which solves the equations of motion. The computer is run in a repetitive operation mode and the stability derivatives are adjusted until the computer solutions match the flight test time histories. This report provides documentation of the computer program that was developed for AFFTC. It is designed as a programmer's manual, but should provide the using engineer with information he needs to use the program effectively. The superiority of the hybrid technique over earlier analog matching programs is obtained by automating the flight data reduction process. By having an engineer directly involved in the matching process, it is possible for the hybrid technique to give more consistantly accurate results than any of the existing digital matching techniques. More meaningful results may be obtained since the engineer can readily determine the accuracy and influence of each derivative upon the particular flight test maneuver being analyzed.

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1971
Accession Number
ADA024281

Entities

People

  • John H. Hofeldt
  • Larry F. Lauber
  • Lon C. Ulmer

Organizations

  • Air Force Test Center

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Analog Computers
  • Computer Programs
  • Computers
  • Data Reduction
  • Digital Computers
  • Engineers
  • Equations
  • Equations Of Motion
  • Hybrid Computers
  • Lifting Bodies

Fields of Study

  • Physics

Readers

  • Aerospace Engineering
  • Database Systems and Applications
  • Robotics and Automation.