The Japanese harnessed air currents to create the first intercontinental weapons—balloons. The project — named Fugo — "called for sending bomb-carrying balloons from Japan to set fire to the vast forests of America, in particular those of the Pacific Northwest. It was hoped that the fires would create havoc, dampen American morale and disrupt the U.S. war effort."

As described by J. David Rodgers of the Missouri University of Science and Technology, the balloon bombs "were 33 feet in diameter and could lift approximately 1,000 pounds, but the deadly portion of their cargo was a 33-lb anti-personnel fragmentation bomb, attached to a 64–foot-long fuse that was intended to burn for 82 minutes before detonating."

Once aloft, some of the ingeniously designed incendiary devices — weighted by expendable sandbags — floated from Japan to the U.S. mainland and into Canada. The trip took several days.

"Distribution of the balloon bombs was quite large," says Nason. They appeared from northern Mexico to Alaska, and from Hawaii to Michigan. "When launched — in groups — they are said to have looked like jellyfish floating in the sky.

In 1984, the Santa Cruz Sentinel noted that Bert Webber, an author and researcher, had located 45 balloon bombs in Oregon, 37 in Alaska, 28 in Washington and 25 in California. One bomb fell in Medford, Ore., Webber said. "It just made a big hole in the ground."

The bomb recently recovered in British Columbia — in October 2014 — "has been in the dirt for 70 years," Henry Proce of the Royal Canadian Mounted Police told The Canadian Press. "It would have been far too dangerous to move it."

So how was the situation handled? "They put some C-4 on either side of this thing," Proce said, "and they blew it to smithereens."

The first balloon was launched on November 3, 1944. Between then and April 1945, experts estimate about 1,000 of them reached North America; 284 are documented as sighted or found, many as fragments (see map). Records uncovered in Japan after the war indicate that about 9,000 were launched.


https://www.npr.org/sections/npr-history-dept/2015/01/20/375820191/beware-of-japanese-balloon-bombs
https://news.nationalgeographic.com/...nt-jet-stream/