Courtesy of BP Drone weighs 13.5 lbs and can stay aloft for three hours. Related Links: FAA Appeals Drone Ruling as Use Soars FAA Drone Information Page The Federal Aviation Administration’s recent approval of BP’s flights of a commercial unmanned aircraft system (UAS), or drone, over northern Alaska, which began on June 8, is a step toward legalizing commercial UAS flights elsewhere in the nation. Until now, legal commercial use of UAS over land has been restricted to the military, law enforcement and scientists engaged in research and development.FAA spokesman Les Dorr says the agency is talking to commercial industries
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.