Aerodynamic Characteristics Of An Ejection Seat Escape System With A Stabilization Parachute At Mach Numbers From 0 3 Through 1 2

A test was conducted in the 16-ft Transonic Wind Tunnel of the Propulsion Wind Tunnel Facility to determine the aerodynamic characteristics of a 0.5-scale ejection seat escape system and to determine the stability effects of a stabilization parachute attached to the back of the ejection seat model. The results were obtained for both simulated rocket-off and rocket-on conditions through a model angle-of-attack range from 0 to 30 deg and an angle-of-yaw range from 0 to 15 deg. High-pressure air was used to simulate the escape rocket jet plume at a sea-level altitude. Over the test range of this investigation, the results show that the ejection seat model was statically unstable but became longitudinally and directionally stable with the parachute using the three- and four-point bridle assemblies. Jet simulation and model yaw angle had little effect on the ejection seat longitudinal stability; however, jet simulation increased the parachute drag coefficient. (Author).

A test was conducted in the Propulsion Wind Tunnel (16T) of the Propulsion Wind Tunnel Facility to determine the flow field in the wake of an ejection seat escape system at transonic flight conditions, and to determine the performance characteristics of a stabilization parachute attached to the back of the ejection seat model. The results were obtained for both simulated rocket-off and rocket-on conditions through a model angle-of-attack range from 0 to 30 deg. High pressure air was used to simulate the escape rocket jet plume at a sea-level altitude. The results show that the ejection seat model was statically unstable, but became longitudinally stable with the parachute for the test range investigated. (Author).

An investigation was conducted at Mach 1.80 in the Langley 4-foot supersonic pressure tunnel to determine the effects of variation in reefing ratio and geometric porosity on the drag and stability characteristics of four basic canopy types deployed in the wake of a cone-cylinder forebody. The basic designs included cross, hemisflo, disk-gap-band, and extended-skirt canopies; however, modular cross and standard flat canopies and a ballute were also investigated. An empirical correlation was determined which provides a fair estimation of the drag coefficients in transonic and supersonic flow for parachutes of specific geometric porosity and reefing ratio.

Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.