Planes have all sorts of parts that you might not expect to be found on the machine. Many moving parts combine to make a wing alone. The wing of an airplane is not the simple, sleek extension of the body it seems to be at first glance but has several components, including the winglets.
Winglets on a plane help reduce vortexes that form due to the difference in pressure between air above and below the wing. This helps stabilize the plane and improves the efficiency of the design, helping the plane burn less fuel.
If you want to learn more about this unique design feature and its unexpected origins, keep reading!
What Are Winglets?
Most people who don’t spend their free time reading about engineering innovations don’t even know what winglets are. However, anyone who’s looked at the tip of a plane’s wing has seen them before—it’s just not common knowledge what they are called.
Winglets are the small vertical flaps at the very end of the wing. These extensions point upward and away from the body of the aircraft. The angle, size, and material of the winglets vary depending on the aircraft, but their purpose and location remain the same.
Winglets were actually invented by NASA before they were adopted by civilian aircraft. The first winglet design was actually developed in the late 19th century, even before the development of heavier-than-air aircraft, but it took nearly a century for the design to become a real device.
Winglets Prevent Vortexes
On normal airplane wings that don’t have winglets, a small vortex will form at the tip of each wing. The air above each wing is low pressure, while the air below is high pressure. As the air extends past the wing, the currents of different air pressure meet and form a vortex.
These vortexes drag the plane down by changing the angle of the lift vector, meaning that the engines have to work harder to continue lifting the plane upwards. Usually, wing vortices aren’t very strong, but sometimes they are enough to destabilize the whole plane, particularly during takeoff and landing.
Wingtips counteract these vortexes by generating their own lift. Wings generate lift perpendicularly to their angle. The winglet’s presence redirects the vortices that form at the wingtip, making them point forwards. Thus, the winglets are able to angle the vortex so that they’re just another wind propelling the airplane forward.
These vortices are usually very small, so it doesn’t seem as if winglets do much. However, flying a passenger jetliner requires a lot of precision, so every little bit helps. Plus, the vortices tend to be strongest during high angles of attack, such as during takeoff, when flying conditions are the most dangerous.
Winglets Improve Airplane Efficiency
Besides making airplanes a bit safer by improving stability, particularly during periods when the plane is at a high angle of attack, winglets also help the airlines save money and make the airplane move more efficiently.
The main effect of wingtip vortices is that they increase the drag on the plane. The engines have to work harder to move the airplane forward and keep it elevated, which in turn burns more jet fuel. Winglets reduce drag, improve the efficiency of airplanes, and help operators save money on jet fuel. They also make it possible for planes to go even faster.
For insight into the money-saving properties of winglets, we only have to look at the history of this engineering innovation. Airlines first began adapting winglets in the 1970s when the oil crisis made jet fuel prohibitively expensive. To this day, airlines use any innovation, from high-altitude cruising speeds to winglets, to improve their bottom line.
Do All Airplanes Have Winglets?
Not all airplanes have winglets. However, most modern aircraft do. You will see winglets on large passenger jets such as the Airbus A319 and the Boeing 747. They are becoming more common on private planes and business jets as well.
Airlines are investing money into making these features even more efficient. For example, many newer planes have blended winglets that attach to the wing with a curve instead of at a 90-degree angle to maximize efficiency.
You won’t see winglets on many vintage aircraft because they were only invented in the 1970s and took a while to catch on (Airbus didn’t add theirs until the 2000s.). However, some companies will retrofit planes that don’t have winglets with this feature so that pilots can enjoy better aerodynamics without having to get a new plane.
Not all passenger planes have winglets, either. For example, the Boeing 777, which is designed for super long-haul flights, is too big to have normal winglets. If Boeing made winglets proportional to the wings, the plane could never dock at a gate!