WASHINGTON, July 7 (Reuters) - The U.S. Federal Aviation Administration (FAA) on Wednesday issued an emergency directive requiring main rotor inspections for some Bell model 212, 204 and 205 helicopters after a fatal crash in Canada last month. The FAA said operators must complete inspections and replace some specified hub strap pins before further flights. On Monday, Transport Canada Civil Aviation issued an emergency directive covering the same issue. The directives impact about 400 helicopters worldwide, with approximately 140 registered in the United States. Bell Helicopter, a unit of Textron Inc (TXT.N), said on Wednesday "even though the investigation is still in progress, to ensure fleet safety, the main rotor strap pins identified... should be removed from service before the next flight." It added it was "not at liberty to discuss details of the Transport Safety Board investigation." Transport Canada said this week that its investigation into the Bell 212 helicopter accident found that one of the outboard main rotor hub strap pins "sheared off during flight, leading to detachment of the main rotor blade and the main rotor head." An inspection of another Canadian Bell 212 helicopter found a main rotor hub strap pin of the same part number to be deformed after only approximately 29 hours in service, Transport Canada said. A 48-year-old pilot died in the June 28 crash near Evansburg, Alberta, as he battled a wildfire, Canadian media reported.