This is made possible by an active articulated torsional drive unit, which in combination with a complex control system attains an unprecedented level of efficiency in flight operation.

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That, and improving efficiency really made human powered-flight move from sustained hops and skips to the international crossings of the Albatross.

ENGADGET: The Highs and Lows of Human-Powered Flight Alt

As an individual, when I look to choose my flight I am looking for the whole package: efficiency, value, convenience, and service.

FORBES: Let's Go Alienate Some Customers Today

Thirteen teams are competing to build a plane that can fly at least 100 miles per hour and achieve the equivalent energy efficiency of 200 miles per gallon of fuel on a 200-mile flight.

FORBES: Google Pushes Electric Planes In Green Flight Challenge

The point of this new flight is to inspire and educate the public in general of the benefits of renewable energy and efficiency, and to encourage school children and university students in particular to "think off the grid" and innovate and invent on their own.

ENGADGET