Objects of arbitrary shapes have to be carried as slung loads under aircraft, particularly rotorcraft. The flight speed is limited by the possibility of slung loads going into divergent oscillations. In 2014 we presented a testing-based approach to predict the safe flight speed, applicable to bluff bodies of arbitrary shape. Since then, an extensive variety of bluff-body shapes has been tested, and we venture further towards generalized airload prediction, required for generalized divergence speed prediction. Extending recent work, the Continuous Rotation method is applied to obtain aerodynamic loads on generic shapes: a circular cylinder and a rectangular prism, both with aspect ratio varied systematically. The genesis of the side force on the yawed cylinder, and the differences between rough and smooth cylinders, have been derived from comparisons between experiments and diagnostic computations with an unsteady Navier-Stokes solver. Interpolating Fourier coefficients of the azimuthal load variation appears to be viable to generalize loads on cylinders of varying aspect ratio for both the generic shapes.
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