Winglets - All Shapes, Sizes - and Uses

Winglets all work in the same basic way, but they don't all look the same. In essence, winglets reduce drag by recovering some of the energy in the wingtip vortex. This provides an effective increase in wing aspect-ratio (span² divided by area - a measure of slenderness), and therefore a reduction in lift-induced drag, for a smaller increase in span, weight and profile drag compared with simply making the wing longer

Once rare, winglets have become commonplace, and over the years their design has evolved to make them more efficient and maximize the fuel savings they provide. Here are some examples of how winglets have changed - and how they could change in the future.

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