National Security Science Podcast

Minuteman III Intercontinental Ballistic Missile Glory Trip

Episode Summary

The knowledge gained from testing the Minuteman III system has become more important than ever—even when things don't go as planned.

Episode Notes

The National Security Science podcast is a spin-off of National Security Science magazine at Los Alamos National Laboratory. We bring you stories from the Lab’s Weapons Program—stories that show how innovative science and engineering are the key to keeping America safe. Or, as we like to say, better science equals better security.

In the summer of 2018, Major Nicholas Edwards was the weapons officer for 576th Flight Test Squadron, the sole group charged with test launching the Minuteman III, the military’s only ground-based nuclear ICBM. These occasional tests, called glory trips, are always done at Vandenberg Air Force Base and are the most exhilarating moments in any missileer’s career.

A glory trip is similar in every way to a real nuclear missile launch, except that the missile’s Los Alamos–designed W78 warhead has been replaced with a joint test assembly (JTA)—also designed and built by the Lab—that replicates a W78 in every way except that it’s filled with sensors, not a nuclear device. The JTA endures the freezing limits of outer space as it exits the atmosphere atop the missile, and after it has dislodged from the ICBM, it endures the molten heat of fall to Earth like a meteor, all the while relaying important flight information to the control center at Vandenberg.

Now that the Minuteman III system is 50 years old, nearing the end of its shelf life, these tests have become more important than ever. In fact, the government planned to retire the system in 2020, but Congress extended its service for another 10 years, at which point a replacement system will be deployed. So until then, the United States randomly picks four Minuteman III missiles annually to test from its stockpile, then compiles the data to share with the military and the Lab. “These glory trips give us a lot of information we can’t get otherwise, and in that way, they’re very useful,” says Jay Pepin, the W78 Systems Engineering group leader at Los Alamos.

There’s also the national defense angle. “Not only do these tests warn us if there are any issues that need to be addressed with the weapon,” says retired Air Force Colonel Michael Port, a former missileer who’s now director of the Lab’s Office of Nuclear and Military Affairs, “they also show our adversaries that we’re still quite capable of using our Minuteman III system, despite its age.”

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Photo for this episode's artwork: U.S. Air Force/Thomas Barley


Previous title: A moment of glory: testing the Minuteman III intercontinental ballistic missile