Delta Air Lines is phasing out blended winglets on its aircraft in favor of more advanced split scimitar winglets, as part of its ongoing efforts to improve fuel efficiency and meet sustainability goals. Winglets, the upward or split extensions at the wingtips of an aircraft, help reduce drag by disrupting air vortices that form at the tips of wings. This allows planes to fly the same distance using less fuel.
The airline was among the first major carriers to install blended winglets across its Boeing 737NG, 757-200, and 767-300ER fleets starting in 2007. At that time, then Chief Operating Officer Jim Whitehurst stated that these upgrades would "deliver at least a 3.5% reduction in fuel burn and a minimum 5% increase in range." Delta eventually equipped most of its narrowbody fleet with this technology.
However, advancements in winglet design have led Delta to invest in split scimitar winglets, which feature both an upward extension and a downward-facing ventral fin. This design further reduces drag compared to the original blended model. According to Aviation Partners, blended winglets save about 3.3% in fuel per aircraft, while split scimitar winglets can achieve up to 5.5% savings.