Experimenter is a magazine created by EAA for people who build airplanes. We will report on amateur-built aircraft as well as ultralights and other other light aircraft.
Issue link: http://experimenter.epubxp.com/i/81495
Celebrating Older Homebui l ts Writing in Sport Aviation in February 1962, Thorp said, "Advocates of wooden airplanes have claimed low cost and simplicity. Actually they are only simple by virtue of being unsophisticated…I believe that Joe Kirk's designs appear simple only because of what is not shown. [At the time, Joe Kirk had a published series of articles highlighting easy-to-build wooden designs.] John T orp's T-18 one of the airplane's unique elements, giving the pilot ample room up front, with a bench seat across the back for three passengers. Like Bowers, Dyke started by building unpowered models of his proposed delta-wing design. He built a mount for the roof of his car for "wind tunnel testing," which helped determine lift and drag. In the "Evolution of the Dyke Delta", he wrote that the most valuable information he gained from those tests "was the craft's actual neutral center of pressure location." He followed that testing by putting a .049 model airplane engine on the model and repeating the testing. He wrote, "A startling difference was noted in the results—lift was increased by from 35 to 40 percent, the model was exceptionally stable, and the engine thrust did not change the trim because the thrust line was symmetrical with [the] airfoil and center of drag." Dyke began construction of his Delta in September 1960, and the fi rst fl ight was made on July 22, 1962. Plans for the Dyke Delta are still available from John Dyke, 2840 Old Yellow Spring Road, Fairborn, Ohio 45324. Thorp T-18 In the same time frame, John Thorp was contemplating developing an all-metal homebuilt. Being an aeronautical engineer at Boeing no doubt increased his familiarity with metal, and he became convinced that an all-metal airplane could be simpler to build than the all-wood aircraft so popular at that time. "I decided to see what I could do with a metal airplane following Kirk's theme…my resulting design, I believe, can be built by an amateur in less time and for less money than any design ever produced for homebuilding regardless of its capability as an airplane." After making that statement, Thorp set about proving it by publishing a series of articles on how to build his T-18 design in Sport Aviation. The articles showed up monthly starting in May 1962. Overall, 14 articles were printed between then and August 1965 when the series concluded. John Thorp fi rst fl ew his T-18 in 1963. Originally designed as an open cockpit airplane, the T-18 evolved into having a sliding bubble canopy before the fi rst plans-built model was completed. With a bent wing reminiscent of the popular Corsair World War II fi ghter, the T-18 went on to become one of the most popular homebuilts of the time, especially after Thorp refi ned the famed matched-hole tooling concept of building. (A CAFÉ fl ight test report about the T-18 is available. See also Budd Davisson's article about Lee Walton's restored T-18 in this issue of Experimenter on page 18.) It's clear that the 1960s was a heyday of homebuilding activity, with nearly all designs built entirely from plans. The beginning of aircraft kits was hinted at when folks like Thorp and others began supplying some parts for builders. Realistically, the number of homebuilt aircraft on the FAA registry would never have surpassed 30,000, as it did a few years back, without the advent of aircraft kits. Still, it's hard not to wax a little melancholy when reading about the classic homebuilts celebrating multiyear anniversaries. 16 NO. 1 / SEPTEMBER 2012