How do you re-create a 1912 airplane when you can’t find a 130-year-old airplane builder to help you?
You do what those craftsmen did: You keep trying until something works.
That was part of the approach to building the replica 1912 Curtiss Pusher biplane on display at Pearson Air Museum. It is a full-scale model of the plane Silas Christofferson flew from the roof of Portland’s Multnomah Hotel to Vancouver Barracks in 1912.
A team of volunteers put in 7,000 hours over a span of two years. They spent a lot of those hours figuring out how aviation designer Glenn Curtiss turned his drawings into working aircraft.
They had some archived resources, including a copy of 1912 Curtiss plans. (The original set is at the National Air and Space Museum.) They also had a 1912 instruction manual, “Build and Fly a Curtiss Aeroplane.”
“Still, there were many details missing, with few living individuals who knew how to accomplish specific tasks,” Bob Cromwell, manager of Pearson Air Museum, said in an email.
• Mike Daly, Vancouver, team leader involved in all aspects of the project
• John Sutter, Linnton, Ore., master woodworker
• Alan Mitchell, Vancouver, researcher, documentarian and finish worker
• Dan Logan, Vancouver, manufacturing engineer and metal fabricator
• Dennis Darby, Portland, manufacturing engineer who was involved in all aspects
• Mike Stansby, Vancouver, Boeing toolmaker who fabricated and installed parts for the replica engine
• Don Erickson, Washougal, who helped install the wing fabric
Wiring for the controls was complex and took a lot of trial and error, using the plans and archive photos.
To provide the airplane’s skin, cotton fabric was tacked onto the wooden airframe and then coated with shellac to shrink it. That’s three daunting challenges right there.
“Thousands of tacks were carefully pounded into position, while attempting to keep the fabric tight and in position,” said Cromwell, who also is chief of interpretation at Fort Vancouver National Historic Site.
To coat the fabric, “We used real shellac, and it took over four months of experimentation,” Cromwell said.
“We got shellac flakes from a place in Port Orford, Ore.,” said Alan Mitchell, a member of the team. “We ground them up with a coffee grinder and dissolved them in alcohol.”
Because of customer demand, modern fabric companies are taking the shrink out of cotton. After some trial and error, the volunteers were able to make the fabric taut.
A piece of unfinished business is the propeller. It’s the correct design for a rear-mounted prop, which pushes the aircraft, but it’s a modern style. There just might be a couple of Christofferson’s original propellers in the area, however.
During Mitchell’s research, he found a 1953 Oregonian newspaper story. It reported that two 1912 Curtiss Pusher propellers from Christofferson’s aircraft were being donated to a Portland aviation club.
If somebody still has one of the century-old props in a garage or man cave, the staff at Pearson Air Museum would love to examine it so they could have it replicated.
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