The Primary Category was established by the FAA in 1993. Under FAR Part 21.24, the Primary Category is an aircraft certification process developed to accelerate and simplify the certification procedure. The traditional certification under FAA Part 23 is extremely expensive and time consuming.

The FAA was motivated to create FAR 21.24 because no light aircraft manufacturer had certified a new aircraft under FAR 23 for many years due to the tremendous cost.

An example of the expedited certification process under FAR 21 is the fact that a manufacturer is allowed to use computer models to extrapolate data. For instance, a manufacturer could flight test an aircraft at 1000 feet and 5000 feet to determine the proper speed for the best rate of climb. Based on the flight information at 1000 and 5000 feet, the best rate of climb speeds at 2000, 3000, and 4000 feet could be obtained by computer, rather than physically test-flying the airplane at each altitude. This method of certification is ideal for ultralight manufacturers, which generally build excellent airplanes, but lack the financial resources for an expensive flight test program and extensive documentation.

When Quicksilver analyzed FAR 21.24, they realized that they could comply with the certification requirements because they had already done most of the flight testing for their own quality control. Under the guidance of President Lyle Byrum and Director of Engineering Tom Price, Quicksilver was able to complete the certification requirements in only a few months. The company was awarded the type certificate for the GT-500 in a ceremony at the EAA Oshkosh airshow in August 1993.

The first person to purchase the certified GT-500 was Jon Thornburgh, who is an FAA and ultralight flight instructor who teaches at various airports throughout the western United States.

Jon’s certified Quicksilver is almost identical to the Quicksilver ultralight trainer. The main difference is that his airplane has a radio and transponder, and is permitted to fly over congested areas, which an ultralight is not permitted to do. However, just like ultralights, Jon’s Primary Category airplane is not permitted to fly at night or in the clouds.

Jon has mostly used the GT-500 to transition FAA pilots from traditional general aviation aircraft to ultralights. Although the GT-500 was designed as a primary trainer for new pilots, no one had actually taken an FAA flight check in the airplane until Todd Cervantes did so last March. The reason is that no FAA examiner was interested in getting "checked out" in an ultralight-type airplane.

After several years of searching, Jon finally found Designated Pilot Examiner (DPE) Cliff Tatum, of Redondo Beach, California. Tatum’s credentials are impressive. He recently retired as a DC-9 Captain for Alaska Airlines, is a former Air Force fighter pilot, and flew combat missions over Viet Nam. Because of his extensive experience, it only took Tatum a few hours to check out in the GT-500 and be comfortable enough in the airplane to give flight examinations in it.

Todd Cervantes was the perfect candidate for the first flight check in the GT-500. At one time he was an employee of Quicksilver, and he was the person who actually did most of the construction of Jon’s airplane at the factory. Eventually, he left Quicksilver to establish his own ultralight flight school in Hemet, California. Todd is an ultralight Advanced Flight Instructor and a Quicksilver dealer.

When Todd decided to get an FAA pilot’s license, the GT-500 was his natural choice for the flight check.

Although Jon Thornburgh and Todd worked together to prepare for Todd’s examination, the flight instructor who actually signed Todd’s flight check application was Jeff Winkler. In addition to being a CFI, Jeff is also an A&P mechanic and a regional jet Captain for Skywest.

So that Todd could get some experience in a traditional FAR 23 aircraft, Jeff instructed him in a Cessna 172, as well as the GT-500. They rested the Cessna from Andy Dutzi’s "The Flight School at Palm Springs," where Jeff is a part-time instructor. Todd took his flight check at Alexair, Torrance Airport, California.

When asked about Todd’s achievement, the new Quicksilver President Carl Van Hersh said that he was extremely pleased. "Thanks to the combined efforts of Jon Thornburgh, Cliff Tatum, and Jeff Winkler, Todd was able to set a precedent that is now available for anyone else who would like to train for his FAA pilot’s license in a light weight, fun-to-fly Primary Category airplane."