The NTSB recommendation was prompted by its probe into the June 8 crash of a Bell 407 near Kalea, Hawaii, in which the tail boom separated from the fuselage during an air tour flight.
NTSB Chair Jennifer Homendy noted there are hundreds of Bell 407 helicopters in service among tour operators, police departments, air ambulance providers and many others.
"We're calling on regulators to act immediately - before there's another accident," Homendy said.
Helicopter maker Bell, a unit of Textron Inc, did not immediately comment.
In the Hawaii accident, the NTSB found the tail boom more than 700 feet from the rest of the helicopter, which crashed in lava-covered terrain. The pilot and two passengers were seriously injured while three other passengers suffered minor injuries.
Asked for comment, the Federal Aviation Administration (FAA) said that last month it issued an alert to operators about Bell 407 helicopter tail booms separating from the fuselage during flight.
The FAA referenced a prior safety directive that requires repetitive checks of the fail boom fasteners every 300 flight hours. The FAA and NTSB noted the helicopter that crashed in June had undergone a check just 114 flight hours before the accident.
The NTSB said operators should check tail boom attachments immediately on all Bell 407 helicopters and the FAA and Transport Canada should reduce the inspection interval from 300 hours to a more conservative number to "increase the likelihood of detecting fractured attachment hardware before a catastrophic failure can occur."
Transport Canada did not immediately comment.
(Reporting by David Shepardson, editing by Deepa Babington)
By David Shepardson