A 113-year-old patent, one of the most important of modern times, was recently found after going missing for 36 years. Patent number 821,393 for a “Flying Machine,” signed by Wilbur and Orville Wright, was found in a special records storage cave in Lenexa, Kansas. The Washington Post reports that on March 22 an archivist found the file in the cave, where it was sent and forgotten about sometime around 1980.

The patent was meant to be placed in the Archives building in Washington, DC, according to National Archives and Records Administration Chief Operating Officer William J. Bosanko. He said that its loss was discovered in 2000 when officials went to fetch the document for a commemoration.

Kansas archivist Bob Beebe found the document in a manila envelope in a stack of records in the limestone storage cave. He sent an email to the Archives complex in College Park, Maryland: “We found it.” Senior conservator Lauren Varga, along with a security escort, brought it home to DC last week after giving it a thorough going over in Maryland. She found it to be in “decent shape.”

It is believed that the patent document was misplaced due to a filing error. “Unfortunately, with billions of pieces of paper, things sometimes go where they shouldn’t be,” Bosanko said. The Archives has been stepping up its Archival Recovery Program as of late in an effort to find missing documents and artifacts, such as telegrams from Abraham Lincoln that were believed to have been stolen.

There was a chance that the Wright patent had been stolen, but as investigative archivist Mitchell Yockelson said, “We felt, I guess, all along … that it was probably misfiled … If somebody puts something back in the wrong place, it’s essentially lost. In this case, we didn’t know. We had to ask ourselves, ‘Is it something that could have been stolen?’ ” Figuring out the misfile among millions of patent papers proved a challenge.

The Archives also lists letters from Civil War generals and World War II bombing maps among its missing documents.

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The Wrights applied for their airplane patent on March 23, 1903, which was less than a month before they started working on it. It was mostly made our of fabric and wood. Nine months later, they produced the world’s first successful flight of a powered heavier-than-air and controllable flying machine on December 17 in Kill Devil Hills, North Carolina. The flight lasted 12 seconds and went 120 feet in distance. The area is now a historic site with the National Parks service.

The patent was found in a file with other documents including letters, affidavits, fee receipts, drawings, photos, and examiner’s notes. One document begins:

“Be it known that we Orville Wright and Wilbur Wright, both citizens of the United States, residing in the city of Dayton and state of Ohio, have jointly invented a new and useful machine for navigating the air.”

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