The drag coefficient for freely falling cones with a vertex angle of was determined experimentally in the Reynolds number range from 90 to and described by empirical equations. The drag was determined by measurement of the terminal velocity of the cones falling through water. Flow-visualization experiments showed the different regimes of the wake structure for a wide range of the Reynolds numbers covering the successive destabilizations of the wake on the way to turbulence. Especially, a very regular staggered array of two rows of ring-shaped hairpin vortices appeared behind the cones in the Reynolds number range from 170 to 235. The Strouhal number was determined in the Reynolds number range from 170 to . The arrangement of the double row of vortex rings and the oscillatory motion of the cones were given in some detail.
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