Airworthiness Directive · Amendment 39-15601 · Bell Helicopter Textron Canada Model 206L, L-1, L-3, L-4, and 407 Helicopters
Bell Helicopter Textron Canada Model 206L, L-1, L-3, L-4, and 407 Helicopters
This AD applies to Models 206L, 206L-1, 206L-3, and 206L-4 helicopters with horizontal stabilizer, part number (P/N) 206-023-119-167, and Model 407 helicopters with horizontal stabilizer, P/N 407-023-801-109, installed, certificated in any category.
We are adopting a new airworthiness directive (AD) for the specified Bell Helicopter Textron Canada (BHTC) helicopters. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority to identify and correct an unsafe condition on an aviation product. The Aviation Authority of Canada with whom we have a bilateral agreement states in the MCAI: "Horizontal stabilizers part numbers 206-023-119-167 and 407-023-801-109 may have manufacturing flaws on the inside surface of the upper and/or lower skin at the tailboom attachment inserts. These flaws may result in cracking of the skin and failure of the horizontal stabilizer." The manufacturer's service information states that in addition to cracks, the horizontal stabilizer may have deformation or debonding around and between the inserts. We are issuing this AD to require actions to correct the unsafe condition on these products.
Within the next 100 hours time-in-service (TIS) or 30 days, whichever occurs first, unless done previously.
(1) Determine whether you have an affected serial numbered horizontal stabilizer installed by removing the elevators from the horizontal stabilizer. Access the horizontal stabilizer identification tag containing the horizontal stabilizer serial number as shown in Figure 1 and remove the elevators by following the Accomplishment Instructions, Part I, of Bell Helicopter Textron Canada (BHTC) Alert Service Bulletin (ASB) No. 206L-06-141, dated September 12, 2006, applicable to the Model 206L series helicopter (206L ASB) or BHTC ASB No. 407-06-72, dated September 12, 2006, applicable to the Model 407 helicopters (407 ASB).
(2) If the serial number on the identification tag is a serial number listed in Table 1 of the 206L ASB or 407 ASB, inspect the horizontal stabilizer as follows:
(i) Using a 10× or higher magnifying glass, inspect the horizontal stabilizer for a crack or deformation around the areas of the inserts. Also, using a tap test method, inspect for debonding between the inserts by following the Accomplishment Instructions, Part II, of either the 206L ASB or 407 ASB, as applicable.
(ii) If you find a crack, deformation, or debonding, replace the horizontal stabilizer with an airworthy horizontal stabilizer that does not have a serial number listed in Table 1 of the 206L ASB or 407 ASB. Replace the horizontal stabilizer by following the Accomplishment Instructions, Part III, of either the 206L ASB or the 407 ASB, as applicable.
(iii) If you do not find a crack, deformation, or debonding, thereafter, at intervals not to exceed 600 hours TIS or during each annual inspection, whichever occurs first, repeat the inspection required by paragraph (e)(2)(i) of this AD.
(f) Replacing any horizontal stabilizer containing a serial number listed in Table 1 of 206L ASB or 407 ASB with a horizontal stabilizer that does not contain such a serial number by following the Accomplishment Instructions, Part III, of either the 206L ASB or 407 ASB, as applicable, constitutes terminating actions for the requirements of this AD.
The MCAI requires compliance “within the next 100 hours air time but no later than 9 May 2007.” This AD requires compliance within the next 100 hours TIS or 30 days, whichever occurs first, unless done previously. Also, the MCAI requires replacing the horizontal stabilizer by September 30, 2008, and we have not mandated a compliance time for replacing the horizontal stabilizer.
Alternative Methods of Compliance (AMOCs): The Manager, Safety Management Group, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN Sharon Miles, Aviation Safety Engineer, FAA, Rotorcraft Directorate, Regulations and Guidance Group, Fort Worth, Texas 76193-0111, telephone (817) 222-5122, fax (817) 222-5961.
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.
