Winglets are a common sight on modern commercial aircraft. These vertical wingtip devices are a key tool in the drive towards designing increasingly efficient airliners, and all major new generation passenger jets are fitted with them. The first widespread use of wing tip devices on commercial aircraft came with the launch of the Boeing 747-400 in 1988.

What do winglets do?

Winglets are essentially aerodynamic performance enhancers. Their primary purpose is to improve aircraft performance by reducing aerodynamic drag. Drag degrades the aircraft’s performance, especially at high speeds and high altitudes where commercial airliners spend most of their time. More drag means less efficiency, more fuel being burned, and more money spent. In short, winglets…

• Extend cruising range
• Improve fuel efficiency
• Save money

In short, it’s a wing wing situation. 

How do winglets work?

Winglets help to reduce the formation of wingtip vortices, which are created by the difference in air pressure on the upper and lower surfaces of the wing. They essentially act as a barrier between these two air flows and stop them from mixing. By reducing this difference in pressure, wingtip vortices are weakened, resulting in less drag. At the launch of the 747-400, Boeing stated that their new Canted Winglets were a major contributor to the aircraft’s 3.5% increase in range over the previous 747-300.

What types of wingtip devices can be seen on commercial aircraft today?

Whilst there are many variations on design, we are going to look at 5 types of winglets commonly seen on airliners in service today.

Blended Winglets 

Fitted to – Boeing 737, 757, 767.

Blended winglets are the most common type of winglets in service today. They are curved gently outwards at the end of the wings and blend seamlessly into the wings themselves. First developed by Gulfstream in the 1990s, the blended winglet is now considered a Boeing design.

Split scimitar winglets

Fitted to – Boeing 737 Next Generation (NG), 737 MAX.

Split scimitar winglets are an enhancement on Boeing’s standard blended winglet design. These feature two distinct pieces, with the lower part angled downwards to reduce drag even further. Airlines such as Ryanair, who operate a large 737-800 fleet, have retrofitted their aircraft with Split Scimitar designs. Boeing enhanced the design even further for the 737 MAX program, launching the aircraft with the ‘Max Advanced Technology (AT) winglet.

Sharklets

Fitted to – Airbus A320 family, Airbus A320neo family, Airbus A350.

The Airbus answer to the Blended winglet can be found on recent A320 and all A320neo family aircraft (including the A319neo, A320neo and A321neo). The Airbus A350 also features a slightly modified sharklet with a distinctive curve, designed to reduce aerodynamic loading.

Raked Wingtips

Fitted to – Boeing 787, 767-400, 777, 777X.

Rumored to be inspired by the wings of gliders and birds, Raked wingtips are a Boeing design found on the Boeing 787 Dreamliner family, 767-400, 777 and 777X. They extend around 5 meters from the end of the wings to create more surface area and reduce drag. Think of it as a ‘flattened down’ winglet. 

Read about the history and future of the ever venerable Boeing 767

Canted Winglets

Fitted to – Boeing 747-400, Airbus A330, Airbus A340

A rarer sight in recent times, Canted winglets were pioneered by the Boeing 747-400, and are also found on older Airbus widebodies such as the A330 and A340. These wingtip devices are short, and feature a distinctive upward slope.

What’s next for the winglet?

It’s hard to deny that wingtip devices have gotten bigger and better over the years. The enhancements brought about by the most recent generation of winglets, combined with new engine technologies, have produced the most efficient gas turbine powered aircraft we have ever seen. It is likely that aircraft manufacturers will continue to make small enhancements to these existing designs to drive that efficiency up a little further. Airlines will most likely continue to retrofit new winglets to older aircraft in the years to come. For example, Ryanair (FR), one of the world’s largest operators of 737NGs, has committed to spending $200 million to retrofit its entire fleet with split scimitar winglets. This will serve as a way to increase their fleet efficiency without buying new aircraft.

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