Why does the FAA make things so complicated? PANS-OPS has the better way of designing these procedures. FAA procedures don't do, or don't do a very good job of dealing with the effects of altitude on turn radius and the effects of wind. PANS-OPS gives you a buffer, so if you find yourself 0.1NM outside the radii, you don't hit anything. With TERPs, all bets are off.