In an Extendable Draft Platform including a deck, a plurality of buoyancy columns installed in column wells in the deck for movement from a raised position to a submerged position, and a heave plate on the bottom of the columns, each of the columns has an upper portion and a lower portion. A helical strake having a radial height H is fixed to the lower portion of each column. The maximum width of the lower column portion is less than the maximum width of the upper column portion by at least 2H, so that the strake can pass through a column well having maximum width that is only slightly greater than that of the upper column portion. A plurality of guide rails is fixed to the lower portion of each column, each extending along the outer periphery of the strake from the upper column portion to the heave plate.

 
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