Nasa unveils shape-changing bird-like plane wing

The new flexible wing was tested on a Gulfstream III jet
Nasa has jointly developed a plane wing that can change
shape during flight.
The US space agency says the new wing will "save millions of
dollars annually in fuel costs, reduce airframe weight and
decrease aircraft noise during take-offs and landings."
The wing features a seamless flexible edge that can move up
or down more subtly than traditional hinged flaps.
The joint project involved Nasa, Air Force Research Laboratory
and private tech firm FlexSys.
During six months of testing, an aircraft featuring the
experimental control surfaces was flown at fixed flap angles
ranging from -2 degrees to 30 degrees for data collection
purposes, Nasa said.
But the flexible Adaptive Compliant Trailing Edge (ACTE) wing
is designed to go through the full range of positions during a
flight, making the operation of the wing much more like that
of a bird.
The seamless trailing wing edge enables smoother air flow
Making the wing seamless allows for smoother airflow, which
reduces friction and so cuts fuel costs.
FlexSys says its smart materials technology, which can be
retrofitted to existing planes, can increase fuel efficiency by
between 5% and 12%, and reduce noise on take-off and
landing by up to 40%.
The conventional jet wing contains ailerons, flaps, slats and
air brakes, all requiring mechanical mechanisms that add
weight and drag.
Prof Jeff Jupp, a former technical director for aircraft
manufacturer Airbus and fellow of the Royal Academy of
Engineering, believes this kind of flexible wing would have only
"a very minor effect on improving fuel burn" for large
passenger jets.
"Mechanical trailing edge flaps are only likely to be totally
replaced on smaller aircraft such as business jets," he told the
BBC.
As it is, the flexible wing is unlikely to replace the traditional
wing any time soon as any new aviation technology has to go
through rigorous safety testing that can take years.