Parachute Filling Time: A Criterion to Classify Parachute Types

Abstract

In low altitude recovery, a parachute must reduce the recovery mass velocity to a predefined velocity prior to its ground impact within a height as low as possible. The article classifies various parachutes based on the parachute opening shock and distance necessary to satisfy the steady descent condition using numerical solution of experimental and theoretical relations of parachute opening and flight dynamics. Results show that the parachute filling time is the main parameter to differentiate all parachutes from each other. Based on the parachute filling time, slotted parachutes’ velocity history coverage locates between Ribbon and Ringsail parachutes whereas solid textile parachutes span a range between Extended skirt 14.3% and Guide surface parachutes. In each group decrease of parachute filling time as a result of the change in the parachute type, causes an increase in the parachute opening shock and a decrease in the parachute steady distance.