The Minuteman missile system relied on knowledgeable and skilled maintainers to keep it reliable and operational, with Air Force enlisted personnel assigned to specialized teams and given extensive, rigorous training in their specialties. The Electro-Mechanical Team handled troubleshooting and repairs across much of the weapon system, including electronic security systems, command and control communication systems, electronic support equipment, power supply systems, and other ancillary equipment, and performed the vast majority of maintenance work in the missile field. The Missile Maintenance Team carried out physically demanding and hazardous duties, including entering launch tubes on a diving board or work cage suspended nearly 80 feet above the silo floor to maintain missile umbilicals, the missile suspension system, and ballistic gas actuators, and it also removed the top portions of the missile, including the re-entry vehicle, war heads, and missile guidance set. The Missile Handling Team transported missiles between Grand Forks Air Force Base and launch facilities, loading them into a transporter-erector and moving them over long distances in all kinds of weather and road conditions; it played a critical role during the early 1970s upgrade from Minuteman II to Minuteman III and in the 1990s removal of missiles before silo implosion. The Facility Maintenance Team ensured launch facilities and launch control centers had continuous power and cooling air by maintaining commercial power connections, backup diesel generators, and air conditioning systems so site electronics would not overheat, and its members could also serve on corrosion control and periodic maintenance teams. These and other teams, including Pneudraulics, Power Refrigeration and Electronics, Electronics Lab, communication maintenance teams, civilian contractors like Rivet MILE, and others, filled an indispensable role in keeping Minuteman missiles on-alert.