Airworthiness Directive · Amendment 39-11651 · Bell Helicopter Textron Canada Model 407 Helicopters
Bell Helicopter Textron Canada Model 407 Helicopters
Superseded. A later AD replaced this one: AD 2003-05-03. Comply with the one in force.
Model 407 helicopters, serial numbers 53000 through 53003, 53005 and higher, certificated in any category.
Note 1: This AD applies to each helicopter identified in the preceding applicability provision, regardless of whether it has been otherwise modified, altered, or repaired in the area subject to the requirements of this AD. For helicopters that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (d) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.
This amendment adopts a new airworthiness directive (AD) applicable to Bell Helicopter Textron Canada (BHTC) Model 407 helicopters. This action requires preflight checking and repetitively inspecting the tail boom for a crack and replacing the tail boom if a crack is found. This amendment is prompted by four reports of cracks on the tail boom in the area of the horizontal stabilizer. The actions specified in this AD are intended to prevent separation of the tail boom and subsequent loss of control of the helicopter.
To prevent separation of the tail boom and subsequent loss of control of the helicopter, accomplish the following:
(a) Before further flight and thereafter before the first flight of each day, check the left side of the tail boom for a crack in the areas shown in Figure 1. If a crack is found, replace the tail boom with an airworthy tail boom before further flight.
(b) An owner/operator (pilot) holding at least a private pilot certificate may perform the visual check required by paragraph (a) but must enter compliance with paragraph (a) into the aircraft records in accordance with 14 CFR 43.11 and 91.417(a)(2)(v)).
(c) Within 25 hours time-in-service (TIS) and thereafter at intervals not to exceed 50 hours TIS, visually inspect any tail boom with 600 or more hours TIS for a crack using a 10X or higher magnifying glass, in accordance with the Accomplishment Instructions, Part II, of Bell Helicopter Textron Canada Alert Service Bulletin 407-99-26, dated April 13, 1999, except that you are not required to contact Bell Helicopter Product Support Engineering. If a crack is found, replace the tail boom with an airworthy tail boom before further flight.
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.
