Why airplanes have wing tips
In a clever marketing move, Qantas has added its logo to airplane winglets, so that every time a passenger snaps a photo from the window, the flying kangaroo will be within frame.
But these wing tips have a much more important function than to look good in photos.
Winglets, or wing tips, are there to reduce something called vortex drag, Qantas explains in a new blog post.
"When an aircraft is flying, air flowing over the top and bottom of the wing creates a long spiral (or, vortex) that forms behind the tip of the wings.
"Even though these spirals look pretty impressive, the drag they create isn't ideal.
"Drag places additional resistance on an aircraft, which means we need to use more power and burn more fuel to counteract it."
By adding winglets, which have only been introduced in recent times, they reduce the amount of air "swirling around at the end of the wing" and reduce the drag.
Not only that, but the winglets give the airplane greater stability, leading to a smoother take-off.
Savvy planespotters can even identify an airplane by the shape of the winglet.
"All of our Boeing 737s have blended winglets which curve up from the end of the wing. Our colleagues over at Jetstar operate similar-sized but Airbus manufactured aircraft called A320s whose winglets are called sharklets," the airline said.
"On our A330 and A380 aircraft the wingtip is triangular in shape while on our Boeing 787-9 Dreamliners (the first of which arrives this year) the entire wing is curved up into what is known as a raked wing tip."
First appeared on Stuff.co.nz.