A Twin-Motored Ultralight Flying Wing – It’s the New Millennium

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Richard Glassock, an Australian now living and working in Hungary, sent the links to YouTube videos of a Millennium hang glider, neatly electrified and flown at this year’s Santa Cruz Salt Flats Race.  Richard has been a speaker at the Electric Aircraft Symposium with a talk on his efforts with small hybrid electric power systems for large-scale models and small aircraft. Steve Morris, co-designer of the Millennium along with Ilan Kroo, Brian Porter, Brian Robbins, and Erik Beckman helped develop this rigid-wing hang glider to offer a lighter, more portable version of Swift.  Steve reported on his electric-powered Swift at the 2010 Electric Aircraft Symposium. Ilan Kroo reflected on the idea of practical, powered ultralight sailplanes in his American Institute of Aeronautics and Astronautics paper on the design of the Swift.  “With refinements in aerodynamic control and composite structures, hang gliders will continue to evolve toward more soarable foot-launched sailplanes. If one does not constrain the designs to be able …

Unique, From A (for Aerodynamics) to Zee

Dean Sigler Electric Powerplants, Sustainable Aviation Leave a Comment

Ilan Kroo, according to his biography page, is a Professor of Aeronautics and Astronautics at Stanford University, an advanced cross-country hang glider pilot, and designer of the Swift flying wing hang glider, unmanned aerial vehicles, a flying Pterosaur replica, America’s Cup sailboats, and high-speed research aircraft.  Currently on a leave of absence from Stanford, he has started Zee Aero, “a bay area start-up company focusing on bringing new technologies to civil aircraft.” Zee Aero, on its first of five sparse web pages, proclaims, “We’re creating an entirely new aircraft,” a heady claim considering the lack of supporting descriptions or illustrations.  But other sources have been made available, including Zee’s patent applications, which show a slim tricycle-gear fuselage surmounted by variously drawn structures holding eight upward-facing propellers and two propellers in the tail, apparently to push the whole assembly along. KGO television sent a news crew to Zee’s Mountain View headquarters, and broadcast nice views of the secure building in which …

Electric, Small, and Challenging

Dean Sigler Electric Powerplants, Sustainable Aviation 4 Comments

Dr. Ilan Kroo, a professor of aeronautics and astronautics at Stanford and designer of the Swift ultralight hang glider, among others, has a different kind of mission – that of reshaping small aircraft for the greatest efficiency. Lessons learned from light aircraft can be applied on a larger scale – but keeping it simple and light to begin with allows less expensive learning, according to Kroo. The outline for his presentation at the fifth annual Electric Aircraft Symposium in Santa Rosa, California on April 29, 2011 is instructive. He had three major topics, all repeating the title for his talk; “Design Concepts for Small Electric Aircraft.” The first topic emphasized the word, “Electric,” the second, “Small,” and the third, “Design Concepts.” First he discussed why electric aircraft are of interest, including their environmental impact, efficiency, reliability, energy source independence, and that fact that they are scalable – the latter being important to anyone also designing lifting body airliners. Modern airliners …