Ribbon Parachute Research Articles

An Omnidirectional Gliding Ribbon Parachute and Control System

These studies have shown that wing/store flutter can be stabilized with adequate stability margins using an active flutter control system which shares the aileron actuation hydraulics with the lateral control system. The flutter control system can be adapted to different store carriage configurations by adjusting the phase and gain characteristics of a generalized electronic compensation network. Control of a flutter mode can be maintained even though the hydraulic actuators are rate saturated for a significant portion of their stroking cycles. Before a flutter control system can be implemented on current aircraft actuator bandwidth should be extended and hydraulic flow rate increased. These improvements are within the current state-of-the-art. It is estimated that the flutter control system with triply redundant components will add about 270 Ib to the aircraft weight.

Supersonic and Transonic Deployment of Ribbon Parachutes at Low Altitudes

Results are presented for twenty-nine flight tests of a 22.2-ft (6.8-m) diameter ribbon parachute (reefed for 0.5 sec) with a nominal 2000-lb (907-kg) store. The design, fabrication, and packing of the parachute system are discussed. Low altitude drop tests were made with F-4 and A-4 aircraft at Mach numbers from 0.57 to 1.22, and rocket-boosted tests were made at Mach numbers from 1.62 to 1.70, the latter corresponding to a maximum dynamic pressure of 2720 psf (130 kN/m2). The maximum measured snatch load, reefed stage opening shock, and second stage opening shock were approximately 65 klb (289 kN), 165 klb (734 kN) and 150 klb (667 kN), respectively. The measured load data and sequence of parachute function times are relatively consistent and repeatable. There is no discernible effect of Mach number on the steady-state drag area of the reefed parachute at Mach numbers from 0.7 to 1.50. Nomenclature At,'Ae = effective canopy inlet and exit areas, respectively, during inflation process

Development of a gliding guided ribbon parachute for transonic speeddeployment

Development of a gliding guided ribbon parachute for transonic speeddeployment

A new solution for the skin-friction drag on a cylinder.

range of 1.92 to 0.44 and values obtained from the upper deceleration curve by using CDS = F/q agree fairly well with the contraves tracking camera trajectory data. The decay in dynamic pressure with time from launch for test 158-13 is shown in Fig. 4. The sharp trajectory alteration at parachute deployment is graphically illustrated in Fig. 5 as obtained from the Contraves Cine theodolites.3 Two coats of RTV silicone rubber cement were applied to the guide surface pilot chute and the suspension lines of the 20-ft chute on all three tests to act as an ablator for the aerodynamic heating resulting from the approximate 500 °F stagnation temperature. Conclusions A series of three Nike/Nike rocket-boosted tests of a specially designed 20-ft-diam ribbon parachute has been conducted. It is concluded that 1) the chute is suitable for use up to M = 2.43 and a dynamic pressure of 5700 psf using a 1100-lb total weight test vehicle system and 2) both the 18-in.diam pilot chute and reefed main 20-ft chute operated in a stable configuration and without damage during deployment.

Recent flight-test results in deploying a 20- ft-diam ribbon parachute.

Recent flight-test results in deploying a 20- ft-diam ribbon parachute.

A 20-ft-diam ribbon parachute for deployment at dynamic pressures above 400 psf.

A 20-ft-diam ribbon parachute for deployment at dynamic pressures above 400 psf.