Accession Number:

AD0729858

Title:

Stability and Drag of Parachutes with Varying Effective Porosity

Descriptive Note:

Final rept. Jun 1958-Jun 1961

Corporate Author:

MINNESOTA UNIV MINNEAPOLIS

Personal Author(s):

Report Date:

1971-02-01

Pagination or Media Count:

76.0

Abstract:

The tangent force, normal force, and moment coefficients versus the angle of attack of ten different types of parachutes were determined by means of wind tunnel measurements. Models formed from sheet metal as well as made out of non-porous and porous cloth were used. The nominal porosity of the cloth varied from 10 to 275 cu ftsq ft min under a differential pressure of 12 inch of water. This corresponds to a range of effective porosity from 0.003 to 0.096. The aerodynamic coefficients were related to the effective and nominal porosity characteristics expressed as derivatives with respect to the porosity term. It was found that the static stability of all types of parachutes could be significantly improved through higher porosity, although this reduces slightly the air resistance for the parachute.

Subject Categories:

  • Gliders and Parachutes

Distribution Statement:

APPROVED FOR PUBLIC RELEASE