The FAA Safety Team (FAASTeam) issued a notice on Friday to alert owners of Bell 407 helicopters to stay vigilant about the fasteners in their tail booms.
The notice comes less than three weeks after an NTSB preliminary report concluded that the tail boom became separated from a Bell 407 helicopter that crashed into a Hawaii lava field in June while providing a sightseeing tour.
The FAASTeam stated that it wants to broaden the awareness of owners and operators in wake of the crash. The FAA issued an airworthiness directive (2012-18-09) that took effect Oct. 22, 2012 regarding the hardware that attaches the tail boom.
It calls for a torque check of the fastening nuts every 300 hours in service or sooner. The NTSB report shows the Bell 407 involved had flown 114.2 hours between the last torque check on May 4 and the crash on June 8.PREVIOUS STORY: NTSB releases public docket in June Bell 407 tour helicopter crash in Hawaii that injured 6 people
The incident injured five passengers and the pilot. Of the six people on board, three were seriously injured - including the pilot and a 19-year-old woman - and three others sustained minor injuries.
It was the helicopter's fourth flight of the day. The pilot told the NTSB that he had performed a thorough pre-flight inspection before the first flight and "found everything to be in order."
The NTSB said the tail boom separated from the fuselage at an altitude of about 1,000 feet, around 35 minutes into the flight. The tail boom was located 762 feet northeast of the main wreckage site.
"As a result of this accident, the operator elected to replace the tail boom attachment hardware on their remaining five Bell 407 helicopters as a precautionary measure," the NTSB report states. "At the request of the NTSB, the operator performed a torque check of all installed attachment hardware prior to their removal. The operator reported no evidence of loose tail boom attachment hardware on their remaining Bell 407 helicopters."
The FAA notice also states the following: "The NTSB's investigation of this event is ongoing. The investigation has included communication with Transport Canada, the government organization with the primary state of design responsibility for airworthiness and continued operational safety of the Bell 407. Likewise, the investigation has included communication with Bell Textron Canada Limited as the original equipment manufacturer (OEM) of the Bell 407 and the FAA as the government organization that is the state of occurrence of the accident and the state of registry for the helicopter. As the investigation progresses, the FAA will continue coordinating with the NTSB, Transport Canada, and Bell Textron Canada Limited as the FAA determines if any mandatory airworthiness action is warranted."