Stud, Spring, and Grommet
In the early 1930s, when aircraft manufacturers began to switch from wood to aluminum alloys, a 36-year-old Ukrainian immigrant working at Fairchild’s American Airplane and Engine Company on Long Island, New York, invented a simple fastener that would make Dzus if not a household name at least a hangar name.
William Dzus (pronounced “Zeus”) observed that when Army Air Corps fighters landed, the cowlings clattered, and he traced the racket to the practice of attaching the cowling panels to the engine rather than to the airframe. The various fasteners of the day were subject to an overload of engine vibration and failed regularly — and when they did, the cowling fell off. Although Common Sense twist-lock fasteners had been in use for 20 years, Dzus designed a quarter-turn fastener that was much more effective in minimizing vibration, and because its spring assembly fit neatly inside the panel it was fastening, it induced much less drag than its predecessors. It could even be counter-sunk to eliminate drag altogether. Dzus fasteners proved invaluable for securing inspection panels and other plates needing a quick release.
Fairchild demanded that Dzus sign over the patent to the fastener or leave. Dzus took off, setting up his own manufacturing facility. In 1932 he received his first order: 16 fasteners, at 25 cents each, from Amphibions Inc. Soon the Army Air Corps named the Dzus fastener the gold standard, and perhaps even used one to secure the 15 pages of “MIL-F-25173A(ASG) Military Specification: Fastener, Control Panel, Aircraft Equipment,” which defined the care and feeding of the Dzus fastener.
After the war, the fastener started showing up on motorcycles, hot rods, and all sorts of equipment that required fast access to its innards. Even the turbojet-powered land speed racers of the 1960s (see “The Bonneville Jet Wars,” Feb./Mar. 2009) relied on Dzus fasteners. Says Tony Moore, an airframe- and-powerplant mechanic in California, “After removing and replacing thousands of screws, I’d say that Dzus fasteners are a blessing to anyone who turns a wrench on an airframe.”
By the time William Dzus died, in 1964, some 6,000 variations on his simple, self-locking fastener had been developed. The company, now called DFCI Solutions, still maintains a plant on Long Island and states proudly on its Web site (www.dfcis.com): “For more than 60 years, [we] have designed a wide range of…devices suited to meet your fastening needs.”