Evaluation of the Aerodynamic Interference of the Tunnel 4T Captive Trajectory System on the Separation Characteristics of the BLU-27 Store

Book excerpt: This report contains the results of an experimental program to evaluate the effect of the 4T Captive Trajectory System on the separation characteristics of typical stores. The models selected as being generally representative of external stores were the modified BLU-27B/B configuration with and without fins. The aircraft model selected for this test was the F-111. To assess the aerodynamic interference of the Captive Trajectory System on the store and its trajectory, four sting lengths were used to position the store model at varying distances from the support system. Data were obtained at Mach numbers of 0.4, 0.8, 0.9, 1.1, and 1.2. Captive trajectories simulating store separation from the aircraft model were obtained; forces on the store were measured while the store was moved vertically away from the marriage position; and force data on the store were obtained as it was yawed in a location as far removed as possible from the aircraft model. It was concluded that the Captive Trajectory System has little or no effect on the store loads and trajectory development. (Author).