The Boeing 787 program has made a subtle but important change to the airplane’s livery to enhance airplane performance.
By developing a method for maintaining a smooth flow of air – laminar flow – over more area on the 787 nacelle inlet, Boeing is able to reduce aircraft drag and fuel consumption.
The 787 nacelle has a tightly controlled smooth surface to preserve laminar flow over a greater distance than that on a standard design. “Aircraft drag is reduced because laminar flow has much lower skin friction drag than turbulent flow,” said Ron Hinderberger, propulsion leader for the 787 program.
To achieve laminar flow over the inlet it is necessary to maintain a very smooth, continuous surface without paint edges, which can occur when paint transitions from one colour to another, or as paint details are added. The design parameter for the nacelles is based on thickness of the paint formulation for a single colour; Boeing has chosen grey to complement the metallic appearance of the nacelle’s inlet.
“If you interrupt the laminar flow by adding paint layers, which are common with airline liveries, you could increase fuel burn by 30,000 gallons per year per airplane,” Hinderberger added. “An improvement like this — especially with rising fuel prices — can contribute positively to the bottom line for an airline.”
To date, 28 airlines have logged 403 orders and commitments worth more than $55 billion at current list prices since the 787 launch in April 2004.