MIAMI -- The crew of a Coast Guard Station Miami Beach, Fla., 45-foot Response Boat-Medium patrols off Miami Dec. 21, 2010. The RB-M, which is replacing the Coast Guard's aging fleet of 41-foot Utility Boats, has a maximum sustained speed of 42.5 knots. U.S. Coast Guard photo by Petty Officer 2nd Class Nick Ameen.