Spiroid winglets

We have become accustomed to seeing blended winglets like this on 737s and now even 757s. These blended winglets reduce fuel burn by 5% which is a big saving. But there's more to this idea. A Seattle company, Aviation Partners, Inc., is developing advanced winglet designs for aircraft it says will cut fuel consumption 6-10 percent in cruise. The company has been testing a new concept - Spiroid Winglets, which look like a large loop of ribbon rigid material attached to each wingtip. Initial flight tests of the Spiroid concept on a GII last year reportedly reduced cruise fuel consumption by more than 10 percent. Winglets are wing-like tip devices which reduce the vorticity strength and concentration thereby reducing drag. The Spiroid concept featuring a closed contour, carries this trend to its logical conclusion, eliminating concentrated vorticity and further reducing drag.