Airworthiness Directive · Amendment 39-13079 · Bell Helicopter Textron Canada Model 407 Helicopters
Bell Helicopter Textron Canada Model 407 Helicopters
Superseded. A later AD replaced this one: AD 2014-04-07. Comply with the one in force.
Model 407 helicopters, serial numbers 53000 through 53475, with tailboom, part number (P/N) 407-030-801-101, - 105 or-107, or P/N 407-530-014-101 or -103, (re-identified in accordance with Bell Helicopter Textron (Bell) Alert Service Bulletin (ASB) 407-01-48, Revision B, dated April 25, 2002), installed, certificated in any category.
This amendment adopts a new airworthiness directive (AD) for the specified Bell Helicopter Textron Canada (Bell) model helicopters that requires preflight checking and repetitively inspecting for a crack in certain tailbooms that have not been redesigned and replacing the tailboom if a crack is found; modifying and re-identifying certain tailbooms and installing an improved horizontal stabilizer assembly; and assigning a 5,000 hour time-in-service (TIS) life limit. This amendment is prompted by cracking discovered in other areas of certain tailbooms and introduction of a redesigned tailboom with a chemically milled skin, which does not require the current inspections. The actions specified by this AD are intended to prevent separation of the tailboom and subsequent loss of control of the helicopter.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
