There is described a color image forming apparatus for forming a color image onto a transfer material by superimposing a plurality of unicolor toner images. The airfoil has a surface contour on the trailing edge region with a forward end having a large amount of taper and a rearward end with less taper such that a substantially constant wall thickness is formed in the rearward end. This air flow resistance layer has an air flow resistance of between 500 Nsm3 and 10,000 Nsm3 and an area mass between 200 gm2 and 3,000 gm2. The cylinders rotate between a parallel condition to the top of the cradle, when fully elevated, and an inclined condition, when the cradle is fully lowered.