Transporting Minuteman missiles and their nuclear warheads was essential to the system’s remove, repair, and replace process, which allowed components of any size to be taken back to Grand Forks Air Force Base for repair and new or repaired parts delivered to launch facilities to replace aged or faulty ones. The system also underwent numerous upgrades, and beginning in 1970 all 150 Minuteman II missiles in the missile wing were removed one after another and replaced with Minuteman III missiles. To carry out these removals, replacements, and transports, the Air Force designed special vehicles. The Payload Transporter handled, transported, installed, and removed the reentry system and warhead, missile guidance set, propulsion system rocket engine, and support equipment in a controlled environment on 3 air cushioned pallets. These components were near the pointed nose of the missile, and maintainers accessed them by parking the Payload Transporter over the silo’s launcher closure door, rolling the door open, attaching a hoist to the components, raising them into the trailer, and transporting them back to Grand Forks Air Force Base. The Transporter Erector was a self-contained environmentally controlled system that transported, removed, and installed Minuteman III intercontinental ballistic missile downstages, or the rocket portion. Missile Handling Team maintainers parked it beside the silo, attached it to stable anchors on either side of the launcher closure door, erected its hydraulic trailer over the silo, opened the launcher closure door, attached pulleys to the missile, hoisted it into the trailer, lowered the trailer back to horizontal, and drove the Transporter Erector and missile back to Grand Forks Air Force Base; the process could be reversed to place a missile into the silo. The Payload Transporter and the Transporter Erector were common sights on eastern North Dakota roads, and moving these critical nuclear components, complete with warheads, required a special security convoy of numerous Air Force security forces, a U.S. Marshal, and a helicopter flying overhead.