Analysis of Static and Dynamic Wind Tunnel Tests of the Shuttle Cable Trays

This article presents the results of a study aimed at determining the possible aeroelastic instability of the Space Shuttle cable trays. Cross flow over the trays, caused by unique flow interference effects, was found to be the potential source of the aeroelastic instability. Selected data from static and dynamic wind tunnel tests of cable tray sections, which furnished the essential input into the aeroelastic analysis, are presented and analyzed. The critical flow phenomena threatening the aeroelastic stability of the trays are shown to be sudden changes in the cross-flow-induced channel flow between the cable tray and the Shuttle external tank, which generate discontinuous aerodynamic characteristics. The search for a successful aerodynamic fix that prevented aeroelastic instability and structural failure of the trays is described.