The effects of tip bluntness, surface roughness, angle of attack, and combinations thereof on the laminar boundary layer for a 10 cone were investigated in the shock tunnel. Platinum heat gages were employed to measure the surface heat transfer and to detect the transition. For the smooth sharp cone at angle of attack, the cross flow promoted transition on the sheltered side of the cone and delayed it on the windward side. Tip bluntness delayed transition while surface roughness promoted transition for both the zero and ±2° angle of attack.