A Near Miss in 1980

I'm aware of a few almost-nuclear-catastrophes of the past, but here's one that was news to me, via a Bluesky account called atomicanalyst, created by Stephen Schwartz, editor and co-author of a book called Atomic Audit: The Costs and Consequences of US Nuclear Weapons Since 1940.

He describes an event that occurred on September 15, 1980 at the Grand Forks Air Force Base in North Dakota. For those not in the Upper Midwest, that's right on the border with Minnesota.

the engine on the right wing of a B-52H on ground alert caught fire during a drill. The aircraft was loaded with 8 Short-Range Attack Missiles (each armed with a 170-200-kiloton W69 warhead) and 4 B28 bombs (70 kilotons to 1.45 Megatons).


That night, a southeast wind gusted up to 35 mph. The B-52 pointed in that direction. That alone kept the flames away from the fuselage. Had the nose been facing west, the fire would have incinerated all six crew members as they evacuated and engulfed the nuclear weapons in the bomb bay.

Because the crew did not follow the correct procedure to shut off the fuel lines before evacuating, the fire burned for three hours. Eventually, a crew member broke through the fire line, climbed into the B-52, and properly engaged the shutoff valves, extinguishing the blaze.

Schwartz goes into great detail about a Grand Forks cop who was ordered to shoot pilots who wouldn't move their tankers away from the burning B-52, and suffered PTSD.

Eight years later, the head of Livermore Labs told Congress

that if the fire had reached the bomb bay, the high explosives “would have detonated” and plutonium would have been scattered across 60 sq. miles of North Dakota and Minnesota.

“You are talking about something that in one respect could be probably worse than Chernobyl,’ [he] testified during the closed hearing, ‘because you have plutonium in the soil and on the soil, which you have to clean up. I wouldn't want either one.’”

Worse still—and unmentioned ...—a design flaw in the B28 bomb meant that if exposed to prolonged heat, two wires too close to the casing could short circuit, arm the bomb, and trigger an accidental detonation of the high explosives surrounding the core, setting off a nuclear explosion.

That would have destroyed Grand Forks (home to approximately 60,000 people) and showered Duluth or Minneapolis-St. Paul with lethal fallout, depending on which way the wind was blowing.

The Air Force subsequently determined the engine fire was caused by a small missing nut on the fuel strainer.

At the time, more than 200 nuclear gravity bombs and Short-Range Attack Missiles (SRAMs) were deployed at Grand Forks AFB. An additional 150 nuclear-armed Minuteman III ICBMs were deployed in underground silos surrounding the base.

In 1990, then-Secretary of Defense Dick Cheney ordered SRAMs removed from all alert bombers after all three nuclear weapons laboratory directors warned that their W69 warheads posed an unacceptable risk in case of fire, an extreme danger they had first warned the DOD about in 1974.

However, SRAMs were not actually removed from the nuclear stockpile until 1993.

There's more detail about the removal of SRAMs in the thread after that.

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Unlike Twitter (the site that wants to be known as X), you have to have a Bluesky account to view its content. I hope I have given enough of a summary.