So close! Zephyr drone lands just hours before setting flight

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Zephyr solar-powered drone smashes record with 2-month-long flight

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Solar Impulse may turn into stratospheric drone - SWI

After 14 Nights in the Air, QinetiQ Prepares to Land its Zephyr Solar Powered Unmanned Aircraft – sUAS News – The Business of Drones

BAE's Phasa-35 drone could replace geostationary satellites - Interesting Engineering