It was only a lump of molten aluminum and four rusty cartridges. But the story behind the recently unearthed debris from a U.S. bomber plane that crashed in England during World War II traces all the way back to an army ammunitions plant in Minnesota — and may help inspire a Twin Cities memorial to commemorate the plant’s wartime role.

“I usually dig up horseshoes,” said Hugh Gibbons, an Englishman who waved a metal detector over a long-forgotten airstrip-turned-horse pasture in England last October, unexpectedly turning up the buried pieces made at the Twin Cities Army Ammunition Plant (TCAAP) in Arden Hills in 1943.

The discovery prompted the 75-year-old former teacher and ad man to contact Ramsey County, which in turn inspired him to create a tiny memorial at the crash site. It has also energized a desire by county officials to find ways to highlight the 427-acre TCAAP site’s prominence in the war years and beyond.

“I think that what he’s done has reinvigorated the interest and excitement around the site, in terms of its history. And that’s important,” said Heather Worthington, assistant Ramsey County manager. “But what’s more important is that people who have heard about it are starting to think about the site and its parallel to World War II as an economic driver. Back then, it was a driver coming out of the Great Depression. Today, it can be the economic driver coming out of the Great Recession.

“I think it shows people what’s possible there,” Worthington said. “They remember what it was, and it can be even better.”

The TCAAP site, which was bought by Ramsey County, is expected to be ready for development in late 2015. A master plan calls for adding housing, office space, manufacturing, retail and parkland. And there is already a building being considered for an interpretive center: Building 189.

Finding a way to commemorate the plant’s role in the war effort has been discussed for some time. But Gibbons’ work has helped serve as a catalyst, said Jonathan Weinhagen, vice president of the St. Paul Area Chamber of Commerce who has worked on the project through the Humphrey Institute.

“Hugh fits into this,” he said. “He is a present-day reality that what was manufactured at TCAAP had a worldwide impact. It would be great to share that story.”

A lump of aluminum

That story dates to October 1943, when an American B-17 Flying Fortress nicknamed “Caboose” thundered into the air from an air field in England, part of a group of nearly 300 bombers on a mission to destroy ball bearings factories in Germany. On a day that would become known as “Black Thursday,” 60 B-17s were destroyed during the mission, with another 17 written off as unrepairable. More than 600 crew members were lost.

The Caboose survived, but ran out of fuel on its return, forcing the pilot to land at another English airfield that was too short for the massive bomber. The plane clipped a mound on its landing, then crashed and burned. Its 10-man crew escaped with only a few injuries. Eventually, the wreckage was cleared, the air field was repaired and the crash was forgotten.

Until last October.

That’s when Gibbons uncovered the lump of molten aluminum and four rusty cartridges stamped “TW43.” Within days, he learned about the crash — and the cartridges. The stamp, he discovered, meant they were made at TCAAP in Arden Hills in 1943.

Gibbons contacted Ramsey County, which sent him historic photos, pins and a couple of bent bullets made at TCAAP to include in a time capsule to be kept at the crash site. A Lutheran minister from Schweinfurt, Germany, the allies’ bombing target 70 years ago, sent dirt to be used to plant a tree at the memorial. A Catholic priest there sent dirt and ball bearings.

“It’s a memorial site, and definitely not a museum,” Gibbons said of Thanksgiving Field, the name he gave to the tiny memorial near the crash site. “Keep in mind that the field is about the whole world, and us today, not one tiny incident among the billions of WWII. This is just a small bit of a pleasant English field, fenced off, with comfy seats and some bits and pieces to get people thinking.”

Since starting his project, Gibbons has talked to relatives of the bomber’s crew and even folks at the Boeing plant in California, where the plane was built. “I have two good things going for me in any activity: First is a big anthology of knowledge — I’m a bit of an information jackdaw,” he said. “Second is curiosity with its sleeves rolled up, so I’m keen to reach out and find links and neat twists.

“This really is just like Topsy, you know — it’s a story with an amazing cast.”