![]() ![]() VG Systems was acquired in 1993 by Beryl D'Shannon (of Bonanza mod fame), who moved the operation to Minnesota and completed the work started by Friday International to obtain STCs for VG kits for the Bonanza A36 and F33. Meantime, Friday International changed its name to VG Systems and obtained additional STCs for VG kits on the Cessna 340 and 421B. More recently, the company has obtained STCs for VG kits for most of the rag*wing strut*braced Piper singles (Cub, Super Cub, Super Cruiser, Pacer andTri*Pacer) and the Maules. This company went on to obtain STC approval for VG kits for numerous piston twins including the Baron 55 and 58, Twin Bonanza, Cessna 310*320*340 and 402*414*421, and Piper Aztec. Disagreements between the partners caused Robertson and White to leave Friday International and, together with their engineering test pilot Bob Desroche, form a new firm called Micro Aerodynamics ( ) in Anacortes, Washington. They also put VGs on an A36 Bonanza but never got far along enough with that project to get an STC.īeginning around 1990, the story of the VG kit business started sounding like a passage from the Old Testament. In 1987, the company managed to secure the first STC for a VG kit on the Beech Barons. The Baron was famous for having a rather nasty stall characteristics on one engine, but Robertson discovered that the VGs turned the airplane into a pussycat and lowered Vmc a full ten knots to the point that it was below stall.Ĭonvinced that VGs had great promise to make piston twins safer, Robertson started a new company called Friday International (located in Friday Harbor, Washington) together with partners Mike Anderson and Chuck White. ![]() Robertson's next VG experiment involved a D*55 Baron that belonged to his partner Mike Anderson. ![]() Robertson first tried out his VG idea on a Cessna 206, but while the VGs did lower the stall speed, it degraded the plane's previously docile stall characteristics, so the project was shelved. The idea of using VGs to improve the low*speed performance of general aviation aircraft came from an ex*Boeing engineer named Paul Robertson. MacDonnell Douglas engineers would routinely scoff at the VGs on Boeing jets and brag, "see, we don't need those things because we got our aerodynamics right in the first place." But historically they were used as an aerodynamic "band*aid" to deal with localized mach buffet problems at the high end of the airspeed envelope. First used in England, VGs have been used on transport jets for decades, and on bizjets since Bill Lear invented them. The use of vortex generators is nothing new. Puzzled and interested I started researching to figure out what this was all about and that's when I went down the rabbit hole. The STC was from ATS (Aeronautical Testing Service, Inc) whom I'd never heard of. When I bought my previous 185 I was surprised to see the contraptions mounted on top of the wings and no VG's on the tail. ![]()
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