The NTSB issued urgent recommendations on Friday for the immediate inspection of the Bell 407 helicopter. They called on American and Canadian aviation to require an immediate inspection as well as more frequent inspections for certain components on the aircraft.
The urgent recommendations follow the investigation of the June 8 crash in Hawaii. The FAA safety team issued a notice in November, alerting owners to stay vigilant about the fasteners in their tail booms. The NTSB preliminary report found that the tail boom separated from the helicopter that crashed in a lava field.
"With hundreds currently in service, the Bell 407 helicopter is a popular model among tour operators, police departments, air ambulance providers, and many others, which is why our finding is so urgent," NTSB Chair Jennifer Homendy said. "We're calling on regulators to act immediately - before there's another accident.RELATED STORIES:
FAASTeam issues tail boom notice for Bell 407 after June tour-copter crashNTSB releases public docket in June Bell 407 tour helicopter crash in Hawaii that injured 6 peopleAccording to the report, the tail boom had separated at 1000 feet altitude. The FAA issued an airworthiness directive (2012-18-09) that took effect Oct. 22, 2012, regarding the hardware that attaches the tail boom. This issue required a torque check of the fastening nuts every 300 hours or sooner. The NTSB report showed the Bell 407 from the June 8 crash had only flown 114.2 hours since its last torque check one month prior.The NTSB revealed that the 300-hour inspection required may not detect any fractured or missing hardware that prevents the tail boom from separating from the fuselage. The agency requests that the FAA and Transport Canada require all Bell 407 owners and operators to seek an immediate inspection of the tail boom attachment hardware.
The NTSB also wants to reduce the 300-hour interval to a more conservative number to "increase the likelihood of detecting fractured attachment hardware before a catastrophic failure can occur."