National Nuclear Security Administration/Nevada Site Office
- In 1957, the US military tested whether or not airships could withstand a nuclear blast.
- Airships were popular in naval combat and briefly considered for the delivery of nuclear weapons.
- In the 1950s, the military tried to nuclearize almost anything it could, a nuclear history expert said.
Almost seven decades ago, the US military wanted to see if its airships — more commonly called blimps — could be potential carriers of nuclear weapons for anti-submarine warfare, so it blasted a few of them with nukes to find out.
The tests were a part of Operation Plumbbob's 24 above-ground nuclear tests from May to October 1957.
According to unclassified documents, the Navy sought to "determine the response characteristics of the Model ZSG-3 airship when subjected to a nuclear detonation in order to establish criteria for safe escape distances for airship delivery of antisubmarine warfare special weapons."
Although the idea of nuclear-armed blimps might seem strange, it's far from surprising, especially considering some of the other developments of the early years of the Cold War, such as nuclear guns, atomic artillery, and nuclear air-to-air missiles, among other things.
"In the 1950s, it was more or less the case that if anything could be nuclearized, we thought about nuclearizing it," Stephen Schwartz, a consultant, writer, and expert on US nuclear weapons history and policy, told Insider. "If we had already used blimps and airships effectively in World War II, then why wouldn't we consider putting nuclear weapons on them?"
As NPR science desk Senior Editor and Correspondent Geoff Brumfiel noted in a recent Twitter thread on this interesting bit of US nuclear history, blimps were especially useful for naval combat. These airships, he said, "could hang around in the air for long periods of time," act as scouts for potential naval threats, like submarines, and drop bombs on enemy targets from safe distances.
Their surveillance and offensive capabilities made them useful, but their slow speeds raised a number of questions about whether airships could drop nuclear weapons and actually survive the devastating explosion.
Naval History and Heritage Command
"And they were right to certainly be concerned," Schwartz said. "A blimp is not an airplane. You can't just drop it off a blimp and scoot away. What happens to the blimp? What happens to the crew, assuming it's crewed?"
With this idea, there were concerns about sacrificing US equipment and personnel to hit Soviet submarines. And according to background information in the unclassified documents, there were also questions about how a nuclear explosion and its shockwave would spread depending on the "depth of burst and receiver altitude."
Testers had the resources to explore all of these though, because no matter how "wild" the ideas got for nuclear testing, Schwartz said, "the costs of nuclear weapons, whether for tests or, more importantly, stockpiling them, were not born by the military." According to Schwartz, "it came out of the Atomic Energy Commission's budget, so it became very easy to create missions for nuclear weapons."
The tests, however, were marred with issues. Documents detail that the tests were difficult to conduct because of weather conditions at the Nevada Test Site. Airships broke free of their mooring, floating away from the site. Others were pushed away by the shockwave of the nuclear blast.
The most significant test of the project was carried out in August 1957. The test, called Shot Stokes, involved detonating a nuclear weapon while the airship hovered about 300 feet off the ground and over 40,000 feet from the detonation point.
Even at that distance, the result was rather conclusive.
National Nuclear Security Administration / Nevada Field Office
According to the testing data, the shockwave crushed the envelope of the airship "within a fraction of a second after shock arrival." Other tears and failures followed, eventually causing the blimp to collapse.
In many nuclear testing situations, the weapons were detonated in the air to avoid generating substantial amounts of radioactive fallout. Air bursts produce greater thermal effects and higher overpressure while blasts close to the ground generate significant fallout.
While a tower was used in one of the Operation Plumbbob tests, Shot Franklin, the nuke used in Shot Stokes was actually tied to a balloon and detonated.
"Those towers were very expensive to build, they're single use, and they take a lot of time," Schwartz said. Using a balloon, tethered so it did not float away, was a "cheaper" and more "pragmatic" option.
The US military eventually developed better aircraft and more effective ways of launching nuclear weapons, and the wild idea of using airships to drop nuclear weapons was lost to history.
"Not surprisingly, they discovered that blimps don't fare too well when exposed to the overpressures of even relatively small nuclear explosions, so that idea didn't go much further than that," Schwartz said.