Aviation Partners Inc. (API) is a Seattle-based private corporation that specializes in performance-enhancing winglet systems. The corporation was founded in 1991 and is owned by The Washington Companies. History API was founded in 1991 by Joe Clark and Dennis Washington, bringing together a team consisting primarily of retired Boeing and Lockheed engineers and flight test department directors. His design team was led by Dr. Louis "Bernie" Gratzer, who retired from Boeing that same year (after a distinguished career which included the aerodynamic design of the KC-135, 707 and 727) and immediately began with API, with title of senior vice president. Washington, a US entrepreneur who made his money from copper mining, was frustrated that his private jet could not fly coast-to-coast in the US without refueling. Instead of buying a new aircraft, he approached his friend Joe Clark who had experience in the aviation industry having co-founded Horizon Air. Clark calculated that by increasing the wings' performance, non-stop coast-to-coast flying would be possible. Together with a group of aviation specialists, Clark developed a new winglet, and with permission from Gulfstream, fitted the winglet to Washington's jet. Test flights confirmed a fuel saving and range increase of 4–5%. Washington and Clark then set out on a publicity campaign to sell the idea. They started setting a number of World Records in performance with the winglets. In 1997, API's winglets were sold as a standard fit on all Boeing Business Jets, and winglets were offered as an addition to standard 737s. Around 95% of all 737 customers want winglets fitted. Aviation Partners formed a joint venture with Boeing, called Aviation Partners Boeing (APB), in 1997. This entity licenses the Blended Winglet Technology for use on Boeing aircraft. Starting with the Boeing Business Jet, winglets have been factory installed onto the Boeing 737 Next Generation as well as retrofitted on 737 'Classic' (Boeing 737-300 and -500) and 757 and 767-300ER airliners. In addition to the Boeing airliner programs, API has certified winglets for the Hawker 800 series jets and has over 100 Blended Winglet equipped Hawkers in service as of December 2008. At EBACE 2007, Dassault Aviation, in conjunction with Aviation Partners, announced the Falcon 2000 LX aircraft. A derivative of the Falcon 2000 EX airframe, it is the first aircraft to be put into production with API's new High Mach winglets. The Falcon 2000-winglets received FAA certification on April 16, 2009, with