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Some time in the next decade, solar-powered European airships might hover 20 kilometres above battlefields, relaying crucial details about the movement of troops below. These extremely high-altitude drones, or pseudo-satellites, haven’t yet taken flight. They’re one of scores of research and development (R&D) projects supported by the European Defence Fund (EDF), a European Union fund that this July announced the winners of its first set of grants, worth €1.2 billion (US$1.24 billion).