Patrol Boat, Riverine, or PBR, is the United States Navy designation for a small rigid-hulled patrol boat used in the Vietnam War from March 1966 until 1975. They were deployed in a force that grew to 250 boats, the most common craft in the River Patrol Force, Task Force 116, and were used to stop and search river traffic in areas such as the Mekong Delta, the Rung Sat Special Zone, the Saigon River and in I Corps, in the area assigned to Task Force Clearwater, in an attempt to disrupt weapons shipments. In this role they frequently became involved in firefights with enemy soldiers on boats and on the shore, were used to insert and extract Navy SEAL teams, and were employed by the United States Army's 458th Transportation Company, known as the 458th Sea Tigers. The PBR was replaced by the Special Operations Craft – Riverine (SOC-R) Design The PBR was a versatile boat with a fiberglass hull and water jet drive which enabled it to operate in shallow, weed-choked rivers. It drew only of water fully loaded. The drives could be pivoted to reverse direction, turn the boat in its own length, or come to a stop from full speed in a few boat lengths. The PBR was manufactured in two versions, the first with length and 10-foot, 7-inch beam. The Mark II version long and wider beam had improved drives to reduce fouling and aluminum gunwales to resist wear. The PBR was designed by Willis Slane and Jack Hargrave of Hatteras Yachts, located in High Point, NC at the time, and its hull was based on an existing Hatteras Yacht hull. Just seven days after a meeting with US Navy officials, Slane and Hargrave had a prototype ready. The 11 PBRs delivered in March 1966 and the approximately 300 delivered over the next few years to the U.S. and South Vietnamese military were based on a pleasure boat design constructed by Uniflite, a boatyard in Bellingham, Washington, on the northern end of Puget Sound near the Canadian border. In October 1965, the Navy awarded a contract to the company for construction of 140 PBRs. The first craft off the assembly line, called the Mark I, was 31 feet long with a hull constructed entirely of fiberglass, a technology developed in the early 1950s. Crew The PBR was usually manned by a four-man crew. Typically, a First