An air vehicle fuselage (2) adapted for transonic operation is disclosed. The fuselage has a body (6) and a close-out (8). A lower surface of the body (6) has a first waterline value at the transition (14) to the close-out. A lower surface of the close-out (8) has a waterline value that varies along a fore-aft direction of the fuselage and is equal to the first waterline value at the transition station (14) and connects to an upper surface of the close-out at an aft end of the close-out. The fuselage (2) also has a drag-reduction blivet (20), i.e. a local deformation deviating from a conventional smooth profile, disposed on the lower surface of the close-out. The blivet includes a first region (A) wherein the lower surface drops to a point comprising a third waterline value that is below the first waterline value and a first inward radius and then rises over a second region (B) disposed aft of the first region wherein a second radius that is a minimum radius of the lower surface within the second region is greater than the first radius.
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