Flight over crowds should never occur and cannot be considered safe practice.
Earlier this year whilst filming in London for the UK version of the X Factor TV show a similar incident took place and was subject to a CAA safety notice. Unlike the UK, Europe, Canada and Australia the USA does not have regulations or safety systems in place for commercial civil UA operations. According to an FAA representative speaking to Patrick Egan of sUAS News at the recent AUVSI conference rules are due for public release and comment before 2013 is out."
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