By David Shepardson WASHINGTON (Reuters) -The Federal Aviation Administration (FAA) on Tuesday issued an airworthiness directive for all Boeing 777 airplanes over safety concerns. The directive was prompted by high electrical resistance within the gust suppression sensor because of corrosion. The FAA said the gust suppression function is a non-essential feature that provides a minor improvement to ride quality during lateral wind gusts at low airspeeds. Airlines must disable the gust suppression function within three months or before 75,000 total flight hours. The directive requires disconnect…