NASA has flown a model aircraft powered only by beamed energy projected from a ground-based laser. The small-scale proof-of-concept model was tested at the Marshall Space Flight Center in Alabama.

The 1.5m (5ft)-span lightweight aircraft, made from balsa wood and composites covered with Mylar film, is fitted with an underslung vertical panel of photovoltaic cells. The ground laser is aimed at the panels, which convert the energy into electricity to power a small electrically driven propeller.

The radio-controlled aircraft was designed and built at NASA Dryden in California and weighs about 0.31kg (0.68lb). The tests build on work conducted on a similar prototype at Dryden in July last year.

The earlier evaluation used a spotlight as an energy source and used a lighter 0.26kg aircraft model.

NASA says success of the proof-of-concept tests could lead to further, larger-scale evaluation of beamed energy concepts for long- duration, high-altitude aircraft intended for communications relays or reconnaissance, but says that the "prime technical focus remains on fuel cell development".

The beamed concept is, however, of interest for use in sustaining solar-powered flight at high latitudes where energy levels in winter can be too low to maintain altitude.

Source: Flight International