The leading edge assemblies and upper covers form part of the NLF wing section on the starboard wing of an Airbus A340 flight test aircraft. These structures are said to offer NLF levels of performance through the adoption of a new design approach and the application of novel manufacturing technologies that are claimed to deliver the ultra-high tolerances and exceptional surface finish required.
“The key challenge with designing and manufacturing an NLF wing, with the many aerodynamic benefits that it promises, stems from the need to tightly control the wing surface,” said Russ Dunn, senior vice president of engineering and technology at GKN Aerospace. “It is vital to eliminate features such as steps, gaps, surface roughness and waviness or fastener heads as these all lead to more traditional ‘turbulent flow’ performance levels.”
Flight tests will take place in 2017 where the NLF wing is expected to show reduction in wing drag of 8% and improved fuel consumption of around 5%.
