Performance-boosting winglets find their way to more bizjets
More than 200 Gulfstream II and Hawker 800/800XP business jets now sport blended winglets developed by Aviation Partners (Stand No.

More than 200 Gulfstream II and Hawker 800/800XP business jets now sport blended winglets developed by Aviation Partners (Stand No. 925) to improve performance by reducing time to climb and fuel consumption, or by increasing range.
They also can enhance the perceived value of an aircraft, according to the U.S.
company’s senior vice president of marketing, Dick Friel.

Winglets, which look like extended wingtips that are curved and slanted upright like a yacht’s sail, improve airflow over the wing to cut overall drag and fuel consumption by up to 7 percent, according to Aviation Partners. In other words, if your unmodified business jet’s range is 1,000 miles, with the change it might be able to fly 15 percent farther. “With blended winglets a Hawker 800 will comfortably fly nonstop from Jeddah to Paris,” Friel told MEBA Convention News.

Winglets now are fitted to more than 3,000 aircraft worldwide, including at least 2,850 Boeing 737 commercial jetliners and all 737-based Boeing Business Jets, and the company has a backlog of orders for another 1,000 sets. Winglets for the 737 were developed by Aviation Partners Boeing, a separate joint venture set up by the two Seattle aerospace companies.

Aviation Partners began making winglets for the Gulfstream GII before moving on to smaller Hawker executive jets and larger Boeing airliners. Most recently it turned its attention to the French Dassault Falcon family, where winglets now are standard equipment on the F2000EX and LX models. The company hopes to receive a supplemental type certificate by the end of the year to retrofit other Falcon 2000s, after which the equipment would be available for installation at authorized Falcon service centers. Next the aerodynamics specialist plans to equip the F900 trijet, scheduled for mid-2009 approval, before addressing the older Falcon 50 trijet.

Following on its development of winglets for the 737, BBJ and 757, Aviation Partners Boeing, in July, began a two-month trial program with a wingletted American Airlines 767-300ER with the aim of achieving certification of the mod by year-end.

It estimates that a modified 767-300ER in airline use would enjoy a reduction in fuel burn of up to 400,000 gallons each year. Boeing’s larger 777 could also be a candidate for possible winglet applications, the company said.

Aviation Partners alludes to many possible winglet applications, but is not forthcoming about particular projects. “Many [airframe manufacturers] look at winglets, but often end up copying us,” said Friel.

Asked specifically about designing winglets for Cessna’s best-selling Citation family of business jets, Friel was circumspect. “We get all sorts of calls, so yes, there’ve been talks with Cessna, but sooner or later all types get mentioned.” While there have been past suggestions about winglets for both straight-wing models and the Citation Xs as future platforms, Friel declined to comment further.

Meanwhile, Airbus has been contemplating a winglet program for its A320 family. It has already conducted some in-house test flights and has had discussions with Aviation Partner’s U.S. competitor Winglet Technology.

However, the European airframer now appears close to pursuing the development with Aviation Partners. Sources close to the program have indicated to MEBA Convention News that initial reference flights to establish A320 baseline performance with an unmodified aircraft will be followed by winglet trials. A launch decision could follow within several months. Officially, by agreement with Airbus, Aviation Partners will say nothing unilaterally.

Friel conceded that some winglet sales may be attributed to the sleeker and more sporty look they can give an aircraft, but he also stressed the environmental benefit that they can yield in terms of reducing fuel burn and carbon emissions. The company claims, for example, that Hawker 800s with winglets save 3.15 pounds of carbon dioxide (CO2) emissions for every unburned pound of fuel.

According to company data, current use of blended winglets on all equipped aircraft saves 17 gallons every second that would otherwise be burned and emitted. That translates to almost 32 million pounds of CO2 each day. Friel said recent record fuel prices have not increased sales but he acknowledged the difference in potential savings between business and commercial use since airliners have perhaps 10 times the annual utilization of an executive jet.

Typically, Aviation Partners winglets are usually fitted in situ by company “swat” teams, however, in September it named South Africa’s National Airways Corp. as the first authorized winglet installer outside North America. A similar move considered in Europe a few years ago did not come to fruition.

There are already three Hawker 800s in Africa fitted with winglets, aircraft that might enjoy enhanced residual value if Aviation Partner’s original experience with the Gulfstream II is repeated. “GIIs with winglets sell more quickly,” said Friel.
Accordingly, GII operators wishing to add value to their winglet-less aircraft should visit the Aviation Partners exhibit here in Dubai because it still has several shipsets left in its inventory.