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).Photocopy.Report was prepared by ARO, Inc., a subsidiary of Sverdrup & Parcel and Associates, Inc."Final Report for Period January 7 - 19, 1972.""Progress Element No. 62201F.""April 1972."Includes bibliographical references (page 6).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).Mode of access: Internet