Accession Number:

ADA058474

Title:

Experimental Measurement of Parachute Canopy Stress During Inflation

Descriptive Note:

Final rept. 1 Jul 1975-30 Dec 1976

Corporate Author:

AIR FORCE FLIGHT DYNAMICS LAB WRIGHT-PATTERSON AFB OH

Personal Author(s):

Report Date:

1978-05-01

Pagination or Media Count:

185.0

Abstract:

The Omega sensor was developed for measuring stress in textile and other flexible materials by the Department of Aerospace Engineering and Mechanics of the University of Minnesota and sponsored by the Air Force Flight Dynamics Laboratory. Two studies were conducted by the University which indicated that the circumferential stresses of inflated parachute canopies indicated by Omega sensors agreed with theoretically predicted stresses and also that the stresses measured by an Omega sensor were not affected by dynamic loading. This particular study deals with an in-house test program, designed to measure the circumferential stresses of a model five foot nominal diameter ringslot parachute during inflation and at steady state using modified Omega sensors. Slight modifications to the original Omega sensor had to be made due to complications of the tabs tearing during preliminary testing. Five sensors were attached strategically to the canopy of a ringslot parachute and put through a series of low speed wind tunnel tests. The results are presented in detail and provide for the first time actual measurement of circumferential stresses on the surface of a model ringslot parachute. These results, however, can only present the general trend shown in the parachutes stress distribution and not actual stress values due to the inability to calibrate the sensor while attached to the canopy.

Subject Categories:

  • Gliders and Parachutes
  • Fluid Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE