Data from thirty one airdrop tests were plotted to show the variation of vertical, horizontal and total velocities and system orientation angle from the vertical as a function of altitude loss from the launch altitude. The purpose was to determine the applicability of using standard G-11A parachutes modified with pulled down vents for airdrop of Army supplies and equipment from an altitude of 500 ft. It was concluded that the ""system second vertical"" was the earliest event which could be considered a suitable criterion for acceptable impact conditions of horizontal and vertical velocity and system orientation angle.
Publisher
Natick, Mass. : Airdrop Engineering Laboratory, U.S. Army Natick Laboratories, 1971.