AD 2020-17-10 Airworthiness Directives; Bell Helicopter Textron Canada Limited Helicopters

This AD replaces AD 2016-02-06, Amendment 39-18387 (81 FR 5367, February 2, 2016).

(1) For T/R link P/N 429-012-112-101 and -103, within 10 hours time-in-service (TIS): (i) Remove each T/R link. Prior to cleaning the T/R link bearing bores, using 10X or higher power magnification, inspect each T/R link bearing bore for aluminum oxide corrosion extruding from between the roll staked lip of the bearing outer race and the link bearing bore. Aluminum oxide corrosion appears as a white crystalline material in contrast with the black finish and any accumulated soot. An example of this corrosion is shown in Figure 1 of Bell Helicopter Alert Service Bulletin 429-15-26, dated December 7, 2015 (ASB 429-15-26). (ii) If there is any aluminum oxide corrosion, replace the T/R link before further flight. (iii) If there is no aluminum oxide corrosion, clean each T/R link bearing bore with isopropyl alcohol, and using 10X or higher power magnification, inspect each cleaned T/R link for pitting. (A) If there is any pitting, replace the T/R link before further flight. (B) If there is no pitting, apply corrosion preventative sealant by following the Accomplishment Instructions, paragraph 5. of Part I, of ASB 429-15-26. (2) For all T/R link P/Ns listed in paragraph (a) of this AD, within 50 hours TIS, and thereafter at intervals not to exceed 50 hours TIS, using 10X or higher power magnification, inspect each T/R link bearing bore for missing corrosion preventative sealant. If any corrosion preventative sealant is missing, perform the actions in paragraphs (f)(3)(i) and (ii) of this AD before further flight. (3) For all T/R link P/Ns listed in paragraph (a) of this AD, within 12 months since date of manufacture, except if paragraphs (f)(1)(i) through (iii) of this AD have already been done for T/R link P/N 429-012-112-101 or -103 within the last 12 months and except if paragraph (f)(3)(i) and (ii) of this AD have already been done for T/R link P/N 429-012-112-101FM, -103FM, -111, -111FM, -113, or -113FM within the last 12 months; and thereafter for all T/R link P/Ns listed in paragraph (a) of this AD at intervals not to exceed 12 months: (i) Remove each T/R link; and (ii) Remove all corrosion preventative sealant, and perform the actions in paragraphs (f)(1)(i) through (iii) of this AD. (4) After the effective date of this AD: (i) Do not install T/R link P/N 429-012-112-101 or -103 on any helicopter before complying with the actions in paragraphs (f)(1)(i) through (iii) of this AD. (ii) Do not install T/R link P/N 429-012-112-101FM, 103FM, -111, 111FM, -113, or -113FM on any helicopter before complying with the actions in paragraph (f)(2) of this AD.

(1) The Manager, International Validation Branch, FAA, may approve AMOCs for this AD. Send your proposal to: Scott Franke, Aviation Safety Engineer, International Validation Branch, Aviation and Rotorcraft Unit, FAA, 10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone 817-222-5110; email scott.franke@faa.gov. (2) For operations conducted under a 14 CFR part 119 operating certificate or under 14 CFR part 91, subpart K, the FAA suggests that you notify your principal inspector, or lacking a principal inspector, the manager of the local flight standards district office or certificate holding district office, before operating any aircraft complying with this AD through an AMOC.

You are responsible for performing each action required by this AD within the specified compliance time unless it has already been accomplished prior to that time.

This AD defines the unsafe condition as failure of a T/R link. This condition could result in loss of T/R flight control and subsequent loss of control of the helicopter.