TULLAHOMA, TN (AP) - Officials of Arnold Engineering Development Center are upgrading a wind tunnel at the U.S. Air Force installation at Tullahoma.

New flexible nozzle actuators have been installed in a 4-foot transonic tunnel known as 4T. The new actuators move the flexible top and bottom plates of the tunnel to provide variable wind speeds or Machs (mox). The tunnel is used to test aerodynamics.

The upgrade will mirror the operations of the A, B and C wind tunnels, giving a similar feel to crews who conduct tests on models in any of the tunnels.

The new gear was designed and fabricated in-house at the air base.

The new nozzles will improve flexible nozzle accuracy and reliability.

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