Seattle-based Aviation Partners claimed yesterday that its blended winglets will save almost 4.5 million gallons of fuel during the current three-day NBAA Convention. The winglets have been installed on more than 4,000 business and commercial aircraft, according to the company, which credited the winglets for total worldwide fuel savings to date of more than 2.3 billion gallons. Aviation Partners is exhibiting here at the NBAA Convention at Booth No. 4508.