How Are OEMs Passively Reducing Carbon Emissions By Lowering Fuel Burn?

Aircraft manufacturers and operators have been findings unique ways to reduce carbon emissions caused by commercial flights. From sustainable design initiatives from manufacturers to using sustainable aviation fuel (SAF) by airlines, the aim is to minimize or offset the amount of carbon emissions the flights produce. Commercial aircraft operators also raise awareness concerning carbon emissions while allowing customers to combat these emissions.

Irrespective of the efforts to offset emissions, aircraft and engine manufacturers (OEMs) produce fuel-efficient designs that passively minimize carbon emissions by reducing fuel burn during flight. Aircraft manufacturers such as Airbus and Boeing produce fuel-efficient airframes and technologically advanced wings to minimize total drag on aircraft during flight. Using lightweight materials on Airbus A350 and Boeing 787 aircraft ensures significantly lower fuel burn than their predecessors.

Similarly, in the narrowbody aircraft market, advanced technology winglets (on Boeing 737s and Airbus A320s) have significantly reduced the formation of wingtip vortices and hence reduced lift-induced drag. Boeing claims that the 737 MAX increases fuel efficiency by 20% while reducing noise footprint by 50%, compared to its predecessors.

Airframe design

Modern airframes implement efficient materials to reduce the weight of the aircraft. The design is optimized to provide a robust relationship between major components that minimize interference drag during flight. Aircraft wings are among the most significant structural components of the aircraft.

Photo: Vincenzo Pace | Simple Flying.

Wings are manufactured with lightweight composites with optimized wing area, wingspan, and aspect ratio. Efficient wing characteristics optimize overall performance within the desired flight envelope.

The size of the wing is determined based on the necessary trade-off between differing requirements at various phases of flight. Large (surface area) wings generate greater lift and minimize takeoff and landing speeds and distance. On the flip side, large wings create more drag, which is particularly detrimental to aerodynamic performance in cruise conditions.

The fuel-efficient wing’s design optimizes lift distribution over the wingspan while carefully catering to the lift-induced drag. The designed wing extensions (flaps) assist at low speeds by increasing the surface area and lift. Moreover, the wing-wetted area provides optimal performance in cruise conditions.

Photo: Vincenzo Pace | Simple Flying

The control surfaces on the wings use efficient design techniques to reduce the overall weight of the wing. Moreover, advanced technology wingtip devices increase cruise fuel efficiency by 2-5%.

Engine design

The ultra-efficient CFM LEAP engines significantly contribute to Boeing 737 MAX’s fuel efficiency. The efficiency of a turbofan engine is typically measured in terms of the consumed fuel per generated thrust.

Modern jet engines are manufactured with greater propulsive efficiency. High bypass ratio engines move larger air mass from the inlet to the exit. While these engines have much greater wetted area, the fuel efficiency outweighs the drag the engines incur during flight.

Photo: airBaltic

Engine fan blades are manufactured using Carbon Fiber Reinforced Plastic (CFRP) to minimize weight and gain material strength. Specialized carbon-based woven fibers are used to manufacture fan blades. Similarly, engine nose cones are designed to modulate oncoming airflow behaviors and minimize aerodynamic drag. Reduced aerodynamic drag requires less fuel to be consumed during the flight. Less fuel burn translates into lower carbon emissions in the environment.

What are your thoughts on OEMs’ passive efforts to reduce carbon emissions through airframe and engine designs? Tell us in the comments section.