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64-651: The Merlin was an evolution of earlier modification programs performed by Swearingen Aircraft. Ed Swearingen started the developments that led to the Merlin through gradual modifications to the Beechcraft Twin Bonanza and Queen Air business aircraft which he dubbed Excalibur . Then a hybrid aircraft was developed, with a new fuselage and vertical fin, mated to salvaged and modified (wet) Queen Air wings and horizontal tails, and Twin Bonanza landing gear:

128-458: A closed-surface Spiroid winglet on a Falcon 50 in 2010. Non-planar wingtips are normally angled upwards in a polyhedral wing configuration, increasing the local dihedral near the wing tip, with polyhedral wing designs themselves having been popular on free-flight model aircraft designs for decades. Non-planar wingtips provide the wake control benefit of winglets, with less parasitic drag penalty, if designed carefully. The non-planar wing tip

192-598: A 170 ft (51.7 m) wingspan to fit in ICAO Aerodrome Reference Code D, as its wingspan was decreased by using blended winglets instead of raked wingtips ), and the Boeing 747-8 (February 8, 2010). The Embraer E-jet E2 and C-390 Millennium wings also have raked wingtips. The McDonnell Douglas MD-11 was the first aircraft with split-tip winglets in 1990. For the 737 Next Generation , third-party vendor Aviation Partners has introduced

256-495: A 6% decrease in in-flight noise from the use of winglets. Actual fuel savings and the related carbon output can vary significantly by plane, route and flight conditions. A wingtip fence refers to the winglets including surfaces extending both above and below the wingtip, as described in Whitcomb's early research. Both surfaces are shorter than or equivalent to a winglet possessing similar aerodynamic benefits. The Airbus A310-300

320-522: A United States engineer, inventor or industrial designer is a stub . You can help Misplaced Pages by expanding it . Winglet Wingtip devices are intended to improve the efficiency of fixed-wing aircraft by reducing drag . Although there are several types of wing tip devices which function in different manners, their intended effect is always to reduce an aircraft's drag. Wingtip devices can also improve aircraft handling characteristics and enhance safety for following aircraft. Such devices increase

384-411: A combination of winglets and increased span to carry the additional load. The winglets increased the 747-400's range by 3.5% over the 747-300, which is otherwise aerodynamically identical but has no winglets. The 747-400D variant lacks the wingtip extensions and winglets included on other 747-400s since winglets would provide minimal benefits on short-haul routes while adding extra weight and cost, although

448-402: A defining feature of all subsequent production models), new landing gear with two wheels on each leg, a redesigned horizontal tail mounted on the vertical fin instead of on the fuselage as in earlier models (This and subsequent Merlin and Metro models have a trimmable horizontal stabilizer (THS) usually used on jet aircraft, one of only two turboprop aircraft types to have this design feature). and

512-511: A given bending moment, a near-vertical winglet offers a greater drag reduction compared to a horizontal span extension. Whitcomb's designs were flight-tested in 1979–80 by a joint NASA/Air Force team, using a KC-135 Stratotanker based at the Dryden Flight Research Center . A Lockheed L-1011 and McDonnell Douglas DC-10 were also used for testing, and the latter design was directly implemented by McDonnell Douglas on

576-485: A given improvement in fuel efficiency correlates directly with the causal increase in the aircraft's lift-to-drag ratio. The initial concept dates back to 1897, when English engineer Frederick W. Lanchester patented wing end-plates as a method for controlling wingtip vortices. In the United States, Scottish-born engineer William E. Somerville patented the first functional winglets in 1910. Somerville installed

640-441: A greater angle, dispensing with the winglets entirely. The Schempp-Hirth Discus-2 and Schempp-Hirth Duo Discus use non-planar wingtips. Tamarack Aerospace Group, a company founded in 2010 by aerospace structural engineer Nicholas Guida, has patented an Active Technology Load Alleviation System (ATLAS), a modified version of a wingtip device. The system uses Tamarack Active Camber Surfaces (TACS) to aerodynamically "switch off"

704-485: A marked dihedral angle . This became a standard feature of the approximately 320 completed He 162A jet fighters built, with hundreds more He 162A airframes going unfinished by V-E Day . The term "winglet" was previously used to describe an additional lifting surface on an aircraft, like a short section between wheels on fixed undercarriage. Richard Whitcomb's research in the 1970s at NASA first used winglet with its modern meaning referring to near-vertical extension of

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768-526: A production aircraft, either civilian or military. Learjet developed the winglet design without NASA assistance. Although the Model 28 was intended to be a prototype experimental aircraft, performance was such that it resulted in a production commitment from Learjet. Flight tests showed that the winglets increased range by about 6.5 percent and improved directional stability. Learjet's application of winglets to production aircraft continued with newer models including

832-584: A redesigned longer nose with room for a baggage compartment as well as the avionics found in the noses of Merlin II series aircraft. All of these design changes came from the Metro design, which was undergoing development in the late 1960s. The SA226-TC Metro was more-or-less a new design, conceptually a stretch of the Merlin II (which it superficially resembled) sized to seat 22 passengers. Prototype construction of

896-400: A same-length winglet, its bending moment is greater. A 3 ft (91 cm) winglet gives the performance gain of a 2 ft (61 cm) span increase but has the bending force of a 1 ft (30 cm) span increase. Raked wingtips offer several weight-reduction advantages relative to simply extending the conventional main wingspan . At high load-factor structural design conditions,

960-417: A similar design to the 737 MAX wingtip device known as the split scimitar winglet, with United Airlines as the launch customer. The Boeing 737 MAX uses a new type of wingtip device. Resembling a three-way hybrid of a winglet, wingtip fence, and raked wingtip, Boeing claims that this new design should deliver an additional 1.5% improvement in fuel economy over the 10-12% improvement already expected from

1024-582: A small improvement in efficiency is a significant competitive advantage. Many non-competition pilots fitted winglets for handling benefits such as increased roll rate and roll authority and reduced tendency for wing tip stall . The benefits are notable, because sailplane winglets must be removable to allow the glider to be stored in a trailer , so they are usually installed only at the pilot's preference. The Glaser-Dirks DG-303 , an early glider derivative design, incorporating winglets as factory standard equipment. Aviation Partners developed and flight tested

1088-520: A small, nearly right-angle, transition area. Once the performance of the winglet itself was optimized, attention was turned to the transition between the wing and winglet. A common application was tapering the transition area from the wing tip chord to the winglet chord and raking the transition area back, to place the winglet in the optimal position. If the tapered portion was canted upward, the winglet height could also be reduced. Eventually, designers employed multiple non-planar sections, each canting up at

1152-408: A technical paper published in 1952 that called for drooped wingtips whose pointed rear tips focused the resulting wingtip vortex away from the upper wing surface. Drooped wingtips are often called "Hoerner tips" in his honor. Gliders and light aircraft have made use of Hoerner tips for many years. The earliest-known implementation of a Hoerner-style downward-angled "wingtip device" on a jet aircraft

1216-439: A winglet-equipped 15-meter class limited wingspan glider, exceeding the highest speed in the unlimited span Open Class , an exceptional result. Masak went on to win the 1993 U.S. 15 Meter Nationals gliding competition, using winglets on his prototype Masak Scimitar . The Masak winglets were originally retrofitted to production sailplanes, but within 10 years of their introduction, most high-performance gliders were equipped from

1280-445: Is now at the tip of the winglet. The fuel economy improvement from winglets increases with the mission length. Blended winglets allow a steeper angle of attack reducing takeoff distance. Richard T. Whitcomb , an engineer at NASA 's Langley Research Center , further developed Hoerner's concept in response to the sharp increase in the cost of fuel after the 1973 oil crisis . With careful aeronautical design he showed that, for

1344-528: Is often swept back like a raked wingtip and may also be combined with a winglet . A winglet is also a special case of a non-planar wingtip. Aircraft designers employed mostly planar wing designs with simple dihedral after World War II, prior to the introduction of winglets. With the wide acceptance of winglets in new sailplane designs of the 1990s, designers sought to further optimize the aerodynamic performance of their wingtip designs. Glider winglets were originally retrofitted directly to planar wings, with only

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1408-489: Is on the Boeing 747 Shuttle Carrier Aircraft . Located on the 747's horizontal stabilizers, the devices increase the tailplane's effectiveness under the weight of the Space Shuttle orbiter , though these were more for directional stability than for drag reduction. Learjet exhibited the prototype Learjet 28 at the 1977 National Business Aviation Association convention. It employed the first winglets ever used on

1472-749: The A320neo , the A330neo and the A350 . They are also offered as a retrofit option. Raked wingtips, where the tip has a greater wing sweep than the rest of the wing, are featured on some Boeing Commercial Airplanes to improve fuel efficiency , takeoff and climb performance. Like winglets, they increase the effective wing aspect ratio and diminish wingtip vortices , decreasing lift-induced drag. In testing by Boeing and NASA, they reduce drag by as much as 5.5%, compared to 3.5% to 4.5% for conventional winglets. While an increase in span would be more effective than

1536-507: The Citation X . Conventional winglets were fitted to Rutan's Rutan Voyager , the first aircraft to circumnavigate the world without refueling in 1986. The aircraft's wingtips were damaged, however, when they dragged along the runway during takeoff, removing about 1 foot (30 cm) from each wingtip, so the flight was made without benefit of winglets. The average commercial jet sees a 4-6 percent increase in fuel efficiency and as much as

1600-1006: The Learjet 55 , 31 , 60 , 45 , and Learjet 40 . Gulfstream Aerospace explored winglets in the late 1970s and incorporated winglets in the Gulfstream III , Gulfstream IV and Gulfstream V . The Gulfstream V range of 6,500 nmi (12,000 km) allows nonstop routes such as New York–Tokyo, it holds over 70 world and national flight records. The Rutan combined winglets-vertical stabilizer appeared on his Beechcraft Starship business aircraft design that first flew in 1986. Winglets are also applied to other business aircraft, reducing take-off distance to operate from smaller airports, and allowing higher cruise altitudes. Along winglets on new designs, aftermarket vendors developed retrofits. Winglet Technology, LLC of Wichita, Kansas should have tested its elliptical winglets designed to increase payload-range on hot and high departures to retrofit

1664-737: The Piper PA-42 Cheyenne and several other fixed-wing aircraft types by bending the blade tips back at a 90-degree angle to get the same thrust from a reduced diameter propeller disk; the reduced propeller tip speed reduces noise, according to the manufacturer. Modern scimitar propellers have increased sweepback at the tips, resembling a raked tip on an aircraft wing. Some ceiling fans have wingtip devices. Fan manufacturer Big Ass Fans has claimed that their Isis fan, equipped with wingtip devices, has superior efficiency. However, for certain high-volume, low-speed designs, wingtip devices may not improve efficiency. Another application of

1728-453: The wing tips . The upward angle (or cant ) of the winglet, its inward or outward angle (or toe ), as well as its size and shape are critical for correct performance and are unique in each application. The wingtip vortex, which rotates around from below the wing, strikes the cambered surface of the winglet, generating a force that angles inward and slightly forward, analogous to a sailboat sailing close hauled . The winglet converts some of

1792-485: The -400D may be converted to the long-range version if needed. Winglets are preferred for Boeing derivative designs based on existing platforms, because they allow maximum re-use of existing components. Newer designs are favoring increased span, other wingtip devices or a combination of both, whenever possible. The Ilyushin Il-96 was the first Russian and modern jet to feature winglets in 1988. The Bombardier CRJ-100 /200

1856-514: The 737 MAX. In 1987, mechanical engineer Peter Masak called on aerodynamicist Mark D. Maughmer , an associate professor of aerospace engineering at the Pennsylvania State University , about designing winglets to improve performance on his 15-meter (49 ft) wingspan racing sailplane . Others had attempted to apply Whitcomb's winglets to gliders before, and they did improve climb performance, but this did not offset

1920-775: The Excalibur Queen Airs; the airstair in the same place and of the same general design as the Queen Air; and the nose being especially similar, of the same general shape with access panels the same size, shape and location as those of the Queen Air. The Australian Department of Civil Aviation (now the Civil Aviation Safety Authority ) took delivery of four Merlin IIBs in 1969 and operated them for almost fifteen years. As of May 2021 there have been 63 documented incidents and 96 deaths involving

1984-966: The Merlin III was replaced by the SA226-T Merlin IIIA , with an extra window on the right side of the cabin and a small window aft of the airstair on each side of the fuselage. Customers for the Merlin IIIA included the Argentinian Air Force , the Argentine Army and the Belgian Air Force . In January 1979 production of the Merlin IIIA ended in favour of the SA226-T(B) Merlin IIIB . The IIIB differed mainly by TPE331-10U engines of increased power driving four-bladed propellers turning in

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2048-568: The Merlin IIIB, and other drag-reducing airframe modifications including landing gear doors that close after the gear is extended. The US Army bought a second-hand Merlin IVC and operated it as the solitary UC-26C. Towards the end of production of the short-fuselage variants of the Merlin, optional winglets were offered. Ten of the last 25 SA227-TTs were built with the winglets as Merlin 300s . Production of short-fuselage Merlins ended in 1983 with

2112-527: The Merlin. The prototype IIA took to the air for the first time on 13 April 1965, about fifteen months after the competing Beech Model 65-90 King Air (which was also derived from the Model 65 Queen Air). 36 Merlin IIA models were built before a follow-on model with Garrett AiResearch TPE-331 -1 engines called the SA26-AT Merlin IIB entered production after AiResearch was appointed as distributor for

2176-442: The Merlin. Listed below are a select few of the most notable ones. Data from Jane's All The World's Aircraft 1982–83. General characteristics Performance Related development Aircraft of comparable role, configuration, and era Related lists [REDACTED] Media related to Swearingen Merlin at Wikimedia Commons Ed Swearingen Edward "Ed" James Swearingen (12 September 1925 – 15 May 2014 )

2240-467: The Metro began in 1968 and first flight was on 26 August 1969. The standard engines offered were two TPE331-3UW turboprops driving three-bladed propellers. A corporate version called the SA226-AT Merlin IV was also marketed and initially sales of this version were roughly double that of the Metro. These sales were not immediately forthcoming however, as the company was financially stretched by

2304-448: The bending moment on the inboard wing. However, the relative aft-movement of the center of pressure accentuates flutter . Raked wingtips are installed on the Boeing 767 -400ER (first flight on October 9, 1999), all generations of Boeing 777 (June 12, 1994) including the upcoming 777X , the 737-derived Boeing P-8 Poseidon (25 April 2009), all variants of the Boeing 787 (December 15, 2009) (the cancelled Boeing 787-3 would have had

2368-580: The building of Merlin IIIC c/n TT-541. The last Merlin IVC (c/n AT-695B) was built in 1987 and Metro production ended in 1998. The SA26 Merlin is a pressurized Excalibur fitted with a different Lycoming TIGO-540 6-cylinder geared piston engine. The TIGO 540 was used despite the fact that one of the reasons the IO-720 was used in the Excalibur was that the Queen Air series' IGSO-480 and IGSO-540 engines from

2432-550: The derivative MD-11 , which was rolled out in 1990. In May 1983, a high school student at Bowie High School in Maryland won a grand prize at the 34th International Science and Engineering Fair in Albuquerque, New Mexico for the result of his research on wingtip devices to reduce drag. The same month, he filed a U.S. patent for "wingtip airfoils", published in 1986. NASA's most notable application of wingtip devices

2496-512: The development of the Metro prototype and lacked the funds to gear up for production. This situation was rectified in late 1971 when Ed Swearingen agreed to sell 90% of the company to Fairchild; the company was then renamed Swearingen Aviation Corporation. By the end of 1972 six Merlin IVs had been built and production gradually built up alongside the concurrently produced short-fuselage Merlin III. In 1974,

2560-422: The devices on his early biplane and monoplane designs. Vincent Burnelli received US Patent no: 1,774,474 for his "Airfoil Control Means" on August 26, 1930. Simple flat end-plates did not cause a reduction in drag, because the increase in profile drag was greater than the decrease in induced drag. Following the end of World War II, Dr. Sighard F. Hoerner was a pioneer researcher in the field, having written

2624-455: The effective aspect ratio of a wing without greatly increasing the wingspan . Extending the span would lower lift-induced drag , but would increase parasitic drag and would require boosting the strength and weight of the wing. At some point, there is no net benefit from further increased span. There may also be operational considerations that limit the allowable wingspan (e.g., available width at airport gates ). Wingtip devices help prevent

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2688-436: The effects of the wingtip device when the aircraft is experiencing high-g events such as large gusts or severe pull-ups. TACS are movable panels, similar to flaps or ailerons , on the trailing edge of the wing extension. The system is controlled by the aircraft's electrical system and a high-speed servo which is activated when the aircraft senses an oncoming stress event, essentially simulating an actuating wingtip. However,

2752-468: The factory with winglets or other wingtip devices. It took over a decade for winglets to first appear on a production airliner, the original application that was the focus of the NASA development. Yet, once the advantages of winglets were proven in competition, adoption was swift with gliders. The point difference between the winner and the runner-up in soaring competition is often less than one percent, so even

2816-468: The first shipset was installed on 14 February 2001 and entered revenue service with Hapag-Lloyd Flug on 8 May 2001. The Aviation Partners/Boeing 8 ft (2.4 m) extensions decrease fuel consumption by 4% for long-range flights and increase range by 130 or 200 nmi (240 or 370 km) for the 737-800 or the derivative Boeing Business Jet as standard. Also offered for the 737 Classic , many operators have retrofitted their fleets with these for

2880-480: The flow around the wingtip of higher pressure air under the wing flowing to the lower pressure surface on top at the wingtip, which results in a vortex caused by the forward motion of the aircraft. Winglets also reduce the lift-induced drag caused by wingtip vortices and improve lift-to-drag ratio . This increases fuel efficiency in powered aircraft and increases cross-country speed in gliders , in both cases increasing range . U.S. Air Force studies indicate that

2944-624: The fuel savings. Aviation Partners Boeing also offers blended winglets for the 757 and 767-300ER . In 2006 Airbus tested two candidate blended winglets, designed by Winglet Technology and Airbus for the Airbus A320 family . In 2009 Airbus launched its "Sharklet" blended winglet, designed to enhance the payload-range of its A320 family and reduce fuel burn by up to 4% over longer sectors. This corresponds to an annual CO 2 reduction of 700 tonnes per aircraft. The A320s fitted with Sharklets were delivered beginning in 2012. They are used on

3008-594: The ground surface during taxiing , takeoff , and hover , these devices can reduce damage from dirt and small stones picked up in the vortices. The main rotor blades of the AgustaWestland AW101 (formerly the EH101) have a distinctive tip shape; pilots have found that this rotor design alters the downwash field and reduces brownout which limits visibility in dusty areas and leads to accidents. Hartzell Propeller developed their "Q-tip" propeller used on

3072-649: The opposite direction to those of earlier models. The SA227-TT Merlin IIIC was next, introduced concurrently with the SA227-AC Metro III (the first Metro III was Fairchild c/n AC-420 and the first Merlin IIIC was c/n TT-421, Metro and Merlin aircraft at this stage being numbered consecutively with different prefixes to denote the different types), and the SA227-AT Merlin IVC version of the Metro III followed shortly after (the first Merlin IVC

3136-686: The original Merlin IV and Metro models were replaced by the SA226-AT Merlin IVA and the SA226-TC Metro II after about 30 Merlin IVs and about 20 Metros had been built. Among the changes made were larger, ovalised rectangular windows replacing the circular porthole -style windows of the early aircraft, and optional provision for a small Rocket-Assisted Take Off (RATO) rocket in the tail cone, this being offered to improve takeoff performance out of "hot & high" airfields. The same year

3200-573: The otherwise-wasted energy in the wingtip vortex to an apparent thrust . This small contribution can be worthwhile over the aircraft's lifetime, provided the benefit offsets the cost of installing and maintaining the winglets. Another potential benefit of winglets is that they reduce the intensity of wake vortices . Those trail behind the plane and pose a hazard to other aircraft. Minimum spacing requirements between aircraft operations at airports are largely dictated by these factors. Aircraft are classified by weight (e.g. "Light", "Heavy", etc.) because

3264-463: The parasitic drag penalty in high-speed cruise. Masak was convinced it was possible to overcome this hurdle. By trial and error, they ultimately developed successful winglet designs for gliding competitions , using a new PSU–90–125 airfoil , designed by Maughmer specifically for the winglet application. At the 1991 World Gliding Championships in Uvalde, Texas , the trophy for the highest speed went to

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3328-538: The same manufacturer were so troublesome. The decision was soon made to offer increased engine power, which was achieved through installing two Pratt & Whitney Canada PT6 A-20 turboprop engines, resulting in the SA26-T Merlin IIA . The Merlin IIAs and IIBs were visually still obviously derivatives of the Queen Air, featuring as they did Queen Air tailplanes and wings with the same flat-top engine nacelles as

3392-445: The smaller chords of the wingtip are subjected to less load, and they result in less induced loading on the outboard main wing. Additionally, the leading-edge sweep results in the center of pressure being located farther aft than for simple extensions of the span of conventional main wings. At high load factors, this relative aft location of the center of pressure causes the raked wingtip to be twisted more leading-edge down, reducing

3456-409: The surface of the wing. Wingtip vortices create turbulence, originating at the leading edge of the wingtip and propagating backwards and inboard. This turbulence 'delaminates' the airflow over a small triangular section of the outboard wing, which destroys lift in that area. The fence/winglet drives the area where the vortex forms upward away from the wing surface, since the center of the resulting vortex

3520-523: The type. The TPE-331 became the definitive engine of all subsequent production Merlins and the longer-fuselage Metros that were to follow. These visual similarities ended with the next model, the SA226-T Merlin III , which was placed in production in February 1972 after 87 Merlin IIBs were built. This had new wings and engine nacelles with inverted inlet Garrett engines (this again becoming

3584-419: The vortex strength grows with the aircraft lift coefficient , and thus, the associated turbulence is greatest at low speed and high weight, which produced a high angle of attack . Winglets and wingtip fences also increase efficiency by reducing vortex interference with laminar airflow near the tips of the wing, by 'moving' the confluence of low-pressure (over wing) and high-pressure (under wing) air away from

3648-530: The wing/winglet junction. A sharp interior angle in this region can interact with the boundary layer flow causing a drag inducing vortex, negating some of the benefit of the winglet. Seattle -based Aviation Partners develops blended winglets as retrofits for the Gulfstream II , Hawker 800 and the Falcon 2000 . On February 18, 2000, blended winglets were announced as an option for the Boeing 737-800 ;

3712-1006: The wingtip itself is fixed and the TACS are the only moving part of the wingtip system. Tamarack first introduced ATLAS for the Cessna Citation family aircraft, and it has been certified for use by the Federal Aviation Administration and European Union Aviation Safety Agency . There has been research into actuating wingtip devices, including a filed patent application, though no aircraft currently uses this feature as described. The XB-70 Valkyrie 's wingtips were capable of drooping downward in flight, to facilitate Mach 3 flight using waveriding . Wingtip devices are also used on rotating propeller , helicopter rotor , and wind turbine blades to reduce drag, reduce diameter, reduce noise and/or improve efficiency. By reducing aircraft blade tip vortices interacting with

3776-893: Was an aeronautical engineer based in San Antonio , Texas . Swearingen was notable for developing modifications from existing production aircraft such as the Piper PA-30 Twin Comanche from the Piper PA-24 Comanche single engine series and the Swearingen Merlin turboprop aircraft from the Beech Model 50 Twin Bonanza . Swearingen also developed original aircraft designs such as the SX-300 experimental airplane and Sino Swearingen SJ30-2 executive jet. This article about

3840-492: Was c/n AT-423). The Merlin IIIC was a redesign to incorporate structural and other changes but was visually the same as the Merlin IIIB, the redesign taking place to make the aircraft compliant with Special Federal Aviation Regulation 41 (SFAR-41). The Merlin IVC version was initially certified in 1980 at up to 14,000 pounds (6,400 kg) this increasing to 14,500 pounds (6,600 kg) as engines and structures were upgraded. An option to go as high as 16,000 pounds (7,300 kg)

3904-614: Was during World War II. This was the so-called "Lippisch-Ohren" (Lippisch-ears), allegedly attributed to the Messerschmitt Me 163 's designer Alexander Lippisch , and first added to the M3 and M4 third and fourth prototypes of the Heinkel He 162 A Spatz jet light fighter for evaluation. This addition was done in order to counteract the dutch roll characteristic present in the original He 162 design, related to its wings having

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3968-523: Was offered. Other improvements incorporated into the Merlin IVC were a 10 ft (3.0 m) increase in wing span (achieved by the simple expedient of removing the wingtips from the Metro II wing, bolting an extension to the end of each wing, and fitting a new wingtip, redesigned to reduce drag), TPE331-11U engines with redesigned "quick-access" engine cowlings and driving four-bladed propellers as on

4032-661: Was the first airliner with wingtip fences in 1985. Other Airbus models followed with the A300-600 , the A320ceo , and the A380 . Other Airbus models including the Airbus A320 Enhanced , A320neo , A350 and A330neo have blended winglets rather than wingtip fences. The Antonov An-158 uses wingtip fences. Boeing announced a new version of the 747 , the 747-400 , in 1985, with an extended range and capacity, using

4096-412: Was the first regional airliner to feature winglets in 1992. The A340 / A330 followed with canted winglets in 1993/1994. The Tupolev Tu-204 was the first narrowbody aircraft to feature winglets in 1994. The Airbus A220 (née CSeries), from 2016, has canted winglets. A blended winglet is attached to the wing with a smooth curve instead of a sharp angle and is intended to reduce interference drag at

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