Delta Pursues 737-800/900 Drag Reduction With Aero Design Lab Kits

Delta Air Lines has signed a memorandum of understanding (MOU) with Aero Design Lab (ADL), targeting supplemental type certification (STC) of the Texas-based company’s drag reduction modification kits on its Boeing 737-800 and 900 fleets. 

Delta says the agreement covers testing and FAA certification of the ADL aerodynamic drag reduction system (ADRS) kit on the 737-800 in the first quarter of 2023, followed by the 737-900 in the second half of 2023. The carrier says it has the option to “outfit most of its more than 200 aircraft in the two fleets.”

The agreement with Delta follows the launch of the initial ADRS STC on the 737-700 with Calgary-based WestJet earlier in 2022 and marks a key step toward ADL’s goal of opening up the drag reduction kit to the broader 737 Next Generation fleet. As well as WestJet and Delta, ADL is understood to be planning demonstrations to other major North American 737 operators in coming months, including Southwest Airlines. 

The ADRS-1 kit consists of a revised wing-to-body aft fairing, modified flap track fairing tips, updated wheel well fairings, revised aerodynamics around the environmental control system (ECS) pack ram air exit duct, and several aft-mounted vortex generators. The modifications are particularly tailored to address areas of interference and parasitic drag around the fuselage that have never previously been tackled or only partially treated over the life of the aircraft.  

Made predominantly from composite structure, the kit weighs 180 lb. but results in a net gain of only 110 lb. after replacement of the original structure. The kit, which is being built by Tulsa-based Nordam and distributed by aviation services company AAR, is expected to require around 150-man hr. to install. 

Delta says the ADL agreement forms part of ongoing initiatives to increase fuel efficiency and improve sustainability. The airline says that in 2022 it expects to have reduced fuel consumption by over 10 million gal. through operational and fleet modifications, such as optimizing flight speeds, improved landing procedures, the installation of enhanced winglets and lightweight landing gear tires.