Summary

  • Winglets are vertical extensions of wingtips that improve fuel efficiency and cruising range by reducing drag caused by vortices.
  • The most popular types of winglets in commercial aviation are canted, blended, split-scimitar, and sharklets.
  • Each type of winglet has its own specific design and benefits, with some being more efficient than others.

Winglets are now a mainstay in commercial aviation. However, their journey has come a long way over the decades. Although they have been conceptualized for over a century, the B747-400 was the first commercial plane to feature these devices.

Boeing highlights that the aircraft's winglets increased its range by 3.5% over the 747-300. Before we look at the different types of winglets, it is important to understand what they are and why they became such a hit.

What is the concept all about?

Winglets are vertical extensions of wingtips. These innovations improve fuel efficiency and cruising range. They are created as small airfoils and reduce the aerodynamic drag associated with vortices that develop at the tips as the aircraft travels.

Reykjavik, Iceland - Circa 2018 Icelandair flight wingtip seen over cloud cover on a flight, looking out the window
Photo: Peter Gudella/Shutterstock
 

The aircraft wing is designed to create a difference in air pressure. When air moves faster, its pressure decreases. The air pressure above the wing is lower than the pressure below, generating lift, which forces the plane to ascend. However, as the wing gets thinner towards the end, the two pressure zones meet, creating a series of vortices.

Larger vortices create more drag, slowing the aircraft down and resulting in more fuel burn. As such, winglets have been incorporated into wing designs to reduce drag and increase the efficiency of an aircraft. They are carefully designed and tested for specific aircraft; therefore, you see different types on various models. Now, let us look at the most popular variants in commercial aviation.

Canted winglets

These devices are noticeably short and are sloped upwards. While they were introduced on the Boeing 747-400, they can also be seen on the Airbus A330 and A340. Unfortunately, with several aircraft that deploy these winglets retiring, spotting them this decade will be a rarity.

Want answers to more key questions in aviation? Check out the rest of our guides here.

Blended winglets

Gulfstream pioneered blended winglets in the 1990s. However, they are commonly used on many Boeing jets, such as the 737s and most 757s and 767s. They gently extend outwards and smoothly blend into the wing, hence the name "blended winglet."

They are probably the most common type in use today. Along with extending range, Boeing states they are proven to reduce drag, increase fuel efficiency, and cut carbon and nitrogen oxide emissions. Moreover, they reduce noise output.

Split-scimitar winglets

You may have noticed that certain Boeing narrowbodies feature what looks like two winglets extending in opposite directions. This is the split scimitar winglet, an improvement of the American manufacturer's standard blended winglet. The lower part is angled downwards, providing even more drag reduction. They can be found on various B737NGs, and some airlines are investing millions in retrofitting their 737s with new split scimitar winglets.

Close up of Boeing 737 MAX winglets
Photo: Boeing

The design was enhanced even further when Boeing introduced the MAX Advanced Technology (AT) winglet for the 737 MAX project. Boeing believes this design provides the greatest fuel efficiency compared to other winglets.

Sharklets

Airbus introduced sharklets with its newer A320-family models. Despite the edgy name, the title is the primary difference between these winglets and Boeing's blended offering. In fact, Airbus faced legal action over the patent of the design. Subsequently, the European manufacturer had to pay out following the dispute.

Today, the design can be seen on various narrowbody aircraft, from the A319 to the A321XLR. Widebodies like the A350 use a blended winglet design, allowing more wing flex and improved efficiency during crucial stages of flight.

Other interesting designs

While almost all modern narrowbodies have distinct winglets, some widebodies fly without them. The B777 does not feature the wingtip extension, so it can fit into the ICAO code E size category, allowing it to serve most global airports. Similarly, the new 777X features a unique folding winglet to reduce the aircraft's wingspan.

The Folding wingtips of a Boeing 777X.
Photo: Arnold O. A. Pinto | Shutterstock

The B787 Dreamliner features a raked wingtip with a greater sweep angle than the rest of the wing. They extend about 5 meters from the end of the wing and have similar effects on vortices as other winglets. Furthermore, the design does not significantly add weight compared to modified wingtips, making the 787 one of the most fuel-efficient widebodies.

Other interesting designs predate modern wingtips. For instance, Airbus placed wingtip fences on its older A320 family aircraft, as well as the A380. These also handle vortices that come from the bottom of the wing. So, they have a physical barrier below and on top of it.

Altogether, there are several different modifications of wingtips. While blended may be spotted more often than others, they all serve the key purpose of reducing drag and improving fuel efficiency.

What are your thoughts about the different types of wingtips, and which is your favorite? Let us know in the comment section below!