Q: Why are the wing ends curved up on some planes?
A: The “curved” wingtips that you refer to are called winglets, which make the wing more aerodynamically efficient by increasing lift and reducing the drag caused by the high- and low-pressure airflows meeting near the tip of the wing. Winglets can reduce fuel consumption by about 5 percent. The different types of winglets we use depend upon the design of the wing itself. The A-320/319 has a small upper and lower design. The B-757 and 767 have an eight-feet-high sweeping design, as do many of the B-737s. We are replacing the current winglets on the B-737 with a newer, more efficient Scimitar winglet, a significant winglet on the lower outboard section of the wingtip, in addition to the sweeping vertical one currently in place.
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