Combat gliders were among the most controversial and dangerous U.S. aircraft of World War II. Silent and engineless, the fragile contraptions of plywood and canvas were towed at night behind cargo planes and released for what were often clandestine missions.

Their nickname says it all -- "flying coffins."

As the world's first "stealth" aircraft, gliders played an important role in America's war effort. On June 6, 1944 -- D-Day -- 500 were in the vanguard of the invasion of France, dropping behind German lines in an attempt to secure vital bridges before the beach invasions.

It may surprise Minnesotans to learn that our state was one of the most important sites for the manufacture of CG-4 gliders. Between 1942 and 1944, 4,000 Twin Citians worked around the clock to build more than 1,500 of the 14,000 manufactured nationwide.

"Gliders made in the Twin Cities landed in small clearings in impenetrable jungles in Burma, retook the island of Corregidor, and participated in D-Day," said Jim Johns, a retired Army aviation officer and glider specialist. Today Johns, of Bloomington, and four other local enthusiasts are restoring a CG-4 glider and plan to return it to the people of Minnesota.

The combat glider was largely the brainchild of Adolf Hitler, according to Johns. In 1940, Hitler's forces astonished the world by capturing Fort Eben Emael in Belgium, once considered impregnable, with only 10 gliders and 78 troops.

After Pearl Harbor, the U.S. Army hoped to duplicate Hitler's success. But American aircraft manufacturers rejected the Army's request out of hand. "They were interested in modern planes -- speed, high performance engines," said Johns. "The idea of going back to the Stone Age of wooden aircraft just didn't seem to make sense to them."

As a result, the Army had to turn to companies with no aeronautical experience -- including Ford Motor Co. and Steinway Piano. In St. Paul, the Villaume Box and Lumber Co. quickly got into the act. Founded in 1882, Villaume was a specialty firm known for installing the beautiful wood paneling in the St. Paul City and County Courthouse.

At Villaume, an unlikely team assembled the gliders -- "Rosie the Riveters" and men who were too old or medically ineligible for the draft. Glider workers included a waiter, a music teacher, a chiropractor, a violin maker, a bank president, a palm reader and a coffin maker, according to Johns.

Their final product was an intricate thing of beauty. Each CG-4 contained 70,000 parts, 69,900 made of wood. The glider was 50 feet long with an 84-foot wingspan, and could carry 13 troops -- or a jeep -- besides the pilot and copilot. The giant craft weighed a feather-light 3,000 pounds.

But the gliders' beauty couldn't disguise the danger faced by the soldiers who manned them. The planes were so fragile that even hitting a sapling on landing could break the crew's legs. German forces booby-trapped almost every field in Italy, Holland or Belgium where gliders could land. On D-Day, many gliders encountered "German asparagus," steel poles set in the ground to rip out the planes' bellies.

Today, there are only seven or eight steel CG-4 frames left in the world, says Johns. After the war, many gliders were left to rot on airstrips.

Johns and his compatriots are restoring their CG-4 at Villaume Industries Inc., with the avid support of its president, Nick Linsmayer, whose great-grandfather founded the company.

Today, their dream is just a rusty frame sitting in a warehouse. But Johns says it will rival the original when completed. He should know. He and Ingemar Holm of Rockford, another member of the group, have reconstructed 18 World War II-era planes, including a Japanese "Kate" torpedo bomber used in the film "Tora, Tora, Tora."

And the CG-4's 70,000 parts? Johns and his colleagues plan to reconstruct many of them, with the aid of volunteers. But they are also looking for help from Twin Citians.

When the Army shut down glider manufacture in early 1945, says Johns, workers were told to take home anything they could use -- from windshield plexiglass and pieces of plywood to instrument panels, shipping crates and even partially constructed wings.

"We know there are parts and pieces out there in Twin Cities basements, attics and garages," he said. "Anyone who brings one in can be guaranteed that it will become part of the project."

Who's going to pilot the giant glider when it's finished? This "flying coffin," Johns made clear, is one vintage aircraft that will stay firmly on the ground.

Katherine Kersten • kkersten@startribune.com

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