Aircraft and propellers were the first glued wood products that the Forest Products Laboratory (FPL) had a hand in developing.
The intricacy of the wooden aircraft wing frame seen below, with glued wood box spars and wood ribs, contains more than 1,000 glued joints.
In the 1910’s during World War I, FPL maintained a propeller laboratory to improve the manufacture of solid and glued-laminated wood propellers.
FPL’s adhesives researchers were also heavily involved in research for aircraft during World War II, including wood-to-wood, wood-to-metal, and metal-to-metal bonding applications.
(Excerpt from John Koning’s book Forest Products Laboratory 1910-2010: Celebrating a Century of Accomplishments.)