While the Boeing B-29 Superfortress program was still a wartime secret, the crash on its first test flight shocked Seattle. More than 30 people died, including 20 from the Frye meatpacking plant that the plane slammed into on Feb. 18, 1943.

TWICE I have heard from people who were working downtown (one in the Exchange Building, the other in the Smith Tower) during World War II when they saw a strange bomber, trailing smoke, sputtering and flying much too low over the business district.

At 12:23 p.m. they heard the still-secret B-29 Superfortress sever with arcing explosions the power lines north of Walker Street and then slam into one of the biggest structures in the industrial neighborhood, collapsing a corner of the Frye meatpacking building that was dedicated to the slaughter of pigs and the manufacture of, among other products, Frye’s Wild Rose Lard.

Those who heard the surreal chorus of squealing pigs that followed the explosion described it as terrifying.

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The death toll for that Feb. 18, 1943, included one fireman, 20 Frye employees, 10 from Boeing who stayed with the plane and two who did not. Most were engineers. Test pilot Edmund T. Allen had turned the plane around in what he probably knew was a hopeless attempt to make it back to Boeing Field, where he’d taken off just minutes earlier. When the bomber was close to colliding with Harborview Hospital, two engineers bailed out, but there was not enough distance between the plane and First Hill for their parachutes to open. Eighty pigs also perished. This famous press photo and scores more are included in Dan Raley’s new book, “Tideflats to Tomorrow: The History of Seattle’s SODO.” SODO — meaning “South of the Dome” — is the name for the neighborhood south of King Street, long ago reclaimed from the tidelands, but more recently divested of its Kingdome. All that, and more, is recounted in the book. Readers can contact the publisher via fairgreens@seanet.com, or check their neighborhood bookstores.

Check out Paul Dorpat and Jean Sherrard’s blog at www.pauldorpat.com.