Delta Air Lines is installing Vortex Control Technologies Finlets on its Boeing 737-800 and 737-900ER aircraft. The aerodynamic devices attach to the aft fuselage to reduce drag and lower fuel consumption. Delta says the retrofit will cover about 240 planes once fully rolled out, following flight tests and engineering reviews. Finlets are a modest efficiency upgrade, but they matter for aviation emissions because fuel burn is the main source of airline CO2. The article does not state expected fuel savings per aircraft or installation cost, so the actual climate benefit is hard to quantify. Still, fleet-wide retrofits like this are part of how airlines cut emissions while waiting for cleaner propulsion.
