Store sep test montage.mpg

Shown here is a montage of store separation testing at AEDC. Store separation testing ensures bombs, missiles, drop tanks, or other stores separate cleanly from the parent aircraft when released.

At transonic speeds, certain altitudes, or manuever conditions, the aerodynamic forces on a store may cause separation from the aircraft. When the separation occurs, it must happen cleanly, if not the store will veer upward when released and collide with the aircraft. In years past, bombs were carried and dropped out of bays. However, as high thrust engines became available, the weapons could be shifted outside and carried in considerable numbers on pylons attached to the lower surface of the wings, as well as in bays. Problems became evident when the aircraft speed became progressively faster.

The dynamics of clean store separation (investigations of aerodynamic forces that can alter the planned projectory of air launched bombs or missiles) are explored in the 16-foot Transonic Wind Tunnel and 4-foot Transonic Wind Tunnel. The aircraft model is mounted upside down in the tunnel on a strut. The store model is mounted on a special moveable support system called a sting attached within the test section and positioned very close to the aircraft as it would be in flight.

When the desired simulated flight conditions are established in the tunnel, the store model is 'launched' from the parent aircraft model by activating a computer that controls movement of the sting-supported store as it traces the trajectory. Information obtained in these tests is used to design new stores or to modify carriage and release mechanisms to make sure they separate cleanly, do not damage the parent aircraft, and stay on the intended flight path in the proper altitude.

Captive Trajectory Support Testing. The CTS systems for AEDC's wind tunnels allow computer-controlled, six-degrees-of-freedom positioning of a missile, bomb, or any other store in close proximity to the aircraft model. Operational CTS systems exist in tunnels 4T and 16T. Applications in the PWT transonic and supersonic test units consist of store separation and flow-field mapping.

Category:

Science & Technology

Tags:

• Store separation
• missile test
• bomb test