Aviation Partners Debuts Spiroid Winglets

Aviation Partners (API) broaught a Falcon 50 equipped with radical-looking spiroid winglets to AirVenture, the airplane’s first public appearance after a two-month installation job at West Star Aviation in East Alton, Ill. The spiroid winglets are strictly a research-and-development program funded by the U.S. government and are not slated for production. The Falcon was limited to 250 knots or Mach 0.7 until it cleared flutter testing, said test pilot Dale Ranz. He hasn’t noticed any difference in handling on the spiroid-equipped Falcon, which uses the same structural wing mods as the normal API Falcon 900/2000 mod. The spiroid winglets are expected to deliver 30 percent more efficiency than the regular API winglets, for an overall improvement of 10 percent, compared with the normal winglets’ 5 to 7 percent. The idea behind the closed-loop spiroid winglets is that they will eliminate tip vortices and thus deliver lower drag. Flight testing will continue over the next couple of months. However, said API chairman and founder Joe Clark, “You’re not going to see this on a [certified] airplane for a long time."