This comparison chart appeared in May 1968. It introduced Minuteman personnel to the latest missile. In the designation LGM-30G, L means silo-launched, G means surface attack, and M stands for guided missile. (U.S. Air Force photo)
A combat crew simulates a Minuteman III launch at F.E. Warren AFB, Wyo. Their launch console is a REACT, or “Rapid Execution and Combat Targeting,” console. It is faster than older systems, but still requires two crewmen to operate -- a single person cannot launch a missile. (U.S. Air Force photo)
Minuteman III missiles can be launched from an airborne command post if ground command centers are disabled. Here, a “Looking Glass” airborne command post crew prepares a test launch in 1991. (U.S. Air Force photo)
The Minuteman III Intercontinental Ballistic Missile (ICBM) is the United States' only current operational land-based strategic nuclear missile. It is one leg of the nuclear deterrent "triad" that also includes USAF bombers and U.S. Navy submarine-launched missiles. U.S. nuclear forces are on alert at all times, ensuring a swift response in the event of a nuclear attack.
Serving Since 1970
Minuteman III became operational in 1970, and is the most modern missile in the Minuteman family. The Minuteman series was the first in the U.S. ICBM arsenal to use solid fuel. This important feature allows the missile to be stored for long periods in its silo, requiring much less maintenance and fewer technicians than older liquid-fueled missiles like Titan and Atlas. It can also be launched almost instantly. Minuteman III was the world's first missile to carry more than one warhead, using a "Multiple Independently-targetable Re-entry Vehicle" (MIRV) system. Though Minuteman III can carry three warheads, each missile has been limited to one by international treaty since 2005.
The Minuteman system was designed in the 1950s. Minuteman I, the first of the family, became operational in 1962 during the Cuban Missile Crisis. Later, the retirement of the U.S. Air Force's Minuteman II missiles in 1995 and Peacekeeper missiles in 2005 left Minuteman III as the only American land-based ICBM. Today, Minuteman III missiles are located in widely-separated, hardened underground silos at three bases -- F.E. Warren AFB, Wyo., Malmstrom AFB, Mont., and Minot AFB, N.D.
Over the years, new technology has increased Minuteman III's reliability, accuracy and ability to survive nuclear attack. Advanced guidance systems, new solid rocket fuel, and improved electrical power are the most recent updates. The Air Force has also upgraded launch facilities and installed better communications gear with new command and control consoles. These improvements enable Minuteman III to serve well into the 21st century.
The Missile Crew Two officers make up a Minuteman III launch crew. These highly-trained USAF teams are on alert at all times in deeply-buried underground launch facilities. Each team controls 10 widely-dispersed missiles. Missile squadrons consist of 50 missiles. Minuteman III crews can launch missiles only on authenticated orders from the President of the United States using complex, secure codes and procedures. A modern system of high- and low-frequency satellite, radio and land lines ensures secure, reliable communication for sending and receiving orders. Airborne command and control aircraft can also launch the missiles remotely if ground command is destroyed.
Launching a Minuteman III takes about 60 seconds. When a launch crew receives a valid "emergency action message," they take specific and well-practiced steps to make sure their actions are correct. If necessary, top-secret codes are sent to the missiles to enable them to launch at predetermined targets. Next, the crewmen simultaneously turn keys that give the missile a final readiness check and open huge silo doors at ground level. Finally, electric cables automatically disconnect to free the missile, the first stage ignites, and Minuteman III is on its way.
Reaching the Target
Minuteman III is a three-stage missile that can reach targets more than 6,000 miles away. As each stage burns out, it drops away and the next stage ignites. In flight, a sophisticated guidance system keeps Minuteman III on course by slightly adjusting rocket nozzles. At the proper time -- about three minutes after launch -- small rockets slow the third stage. The post-boost vehicle (or "warhead bus") carrying the nuclear payload then maneuvers to a pre-determined release point. With precise timing, it releases the warhead or "re-entry vehicle." Helped by penetration aids that disguise it on enemy radar, the warhead follows a ballistic trajectory to its target.
TECHNICAL NOTES: Propulsion: Three-stage solid fuel rocket motors; post-boost stage for positioning re-entry vehicle is liquid-fueled Weight: 76,000 lbs. Range: 6,000+ miles Maximum speed: Approx. 15,000 mph Armament: One, two or three MK-12 or MK-12A warheads in the megaton range