Owls, however, possess no fewer than three distinct physical attributes that are thought to contribute to their silent flight capability: a comb of stiff feathers along the leading edge of the wing; a soft downy material on top of the wing; and a flexible fringe at the trailing edge of the wing.
The researchers attempted to unravel this mystery by developing a theoretical basis for the owl's ability to mitigate sound from the trailing edge of its wing, which is typically an airfoil's dominant noise source.
Each trailing edge
is 36 metres long and is being delivered in four sections each, because of its size, requiring a purpose-built lorry.
The processing of leading and trailing edges
is ideally suited to mechanical surface finishing process because of the true radius produced, but care must be taken to maintain the chordal width of the blade.
At some point, the blades become too thin to do that, so they peel off some skin at the end of the blade and let the air run over the trailing edge
," said Benson.
For takeoffs and landings, the leading and trailing edges
curve downward; in normal flight, both edges are slightly less curved; and at high speeds, the airfoil is flattened, with the leading edge pointing slightly upward.
The contract includes the fabrication of new tooling to manufacture inboard slats (leading edge flaps), ailerons, forward main landing gear fairings, flap torque boxes and an assortment of wing panels, structural supports, fairings, leading and trailing edges
and fire compartment shields.
The final test took place on 21 April, when the wing and trailing edges
were subjected to their limit load.
The Controls business segment designs, engineers and manufactures actuation components and systems used for leading and trailing edges
wing flaps on commercial and military aircraft; systems for opening and closing weapons bay doors on fighter aircraft, suspension systems and turret stabilising and aiming systems for armored vehicles, integrated mission management and flight control computers, ammunition handling and fire control systems, and perimeter intrusion detection systems.
The complete wing assembly includes flaps, ailerons, leading edges and trailing edges
, as well as installed sub-systems.
The company estimates that by using KBE to design the A380 and A400M trailing edges
, at least 50 % cost savings will be achieved, along with significant time savings.
Several research studies have shown that blunt trailing edge
(flatback) airfoils have a larger moment of inertia and manufacture facilities, in addition to an aerodynamic performance as good as the one shown by the use of common airfoils [4-15].