Bendable wings covered with overlapping (重疊部分) pieces looking like fish scales could be used to build more controllable, fuel?efficient aircraft, a new study finds.

Nowadays, conventional aircraft typically rely on ailerons (副翼) to help control the way the planes tilt (傾斜) as they fly. However, when the Wright brothers flew the first airplane, Flyer 1, over a century ago, they used no ailerons but wires that pulled and stretched the wood?and?canvas wings, to control the plane.

“Scientists have long sought to develop aircraft that can change their wings during flight, just as birds can. However, most previous attempts have failed because they relied on heavy mechanical control structures within the wings. These structures were also complex and unreliable，” said Neil Gershenfeld, a physicist and director of the Centre for Bits and Atoms at MIT.

The new wing consists of a system of tiny, strong and lightweight modules (組件). The shape of the wing can be changed uniformly along its length using two small motors, which apply a twisting pressure to each wingtip. These wings are covered in “skins” of overlapping strips of flexible material like fish scales. These strips move across each other as the wings change themselves, providing a smooth outer surface, the researchers explained.

Wind tunnel tests of these wings showed that they at least matched the aerodynamic (氣動) properties of conventional wings, at about one?tenth the weight. “Initial tests using remotely piloted aircraft made with these wings have shown great promise，” said Benjamin Jenett, a graduate student at the Centre for Bits and Atoms at MIT.

The new modular structures the scientists developed could be manufactured quickly in mass quantities and then installed by teams of small robots. These modular structures also can be disassembled more easily, making repairs simpler.

“Still, the first aircraft built using this strategy will not be a passenger jet，” Gershenfeld said. “Instead, the technology will likely first be tested on unmanned aircrafts, leading to aircrafts flying for a long time, to help deliver Internet access or medicine to remote villages.”

1.Why is the Wright brothers' airplane mentioned in the text?

A. To show the history of aircrafts.

B. To show the development of wings.

C. To show the need to improve planes.

D. To show the structure of conventional planes.

2.What makes planes fly like birds when they tilt?

A. Their ailerons. B. Wires and pulleys.

C. Changeable wings. D. Mechanical control structures.

3.What is Paragraph 4 mainly about?

A. The shape of the new wings.

B. The purpose of the overlapping strips.

C. The working principle of the new wings.

D. The result of wind?tunnel tests of these wings.

4.What does the underlined word “disassemble” mean in Paragraph 6?

A. Replace. B. Analyze.

C. Put away. D. Take apart.

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