Airworthiness Directive · Amendment 39-22120 · Stabilizers
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 787-8, 787-9, and 787-10 airplanes, certificated in any category, as identified in Boeing Alert Requirements Bulletin B787-81205-SB550010-00 RB, Issue 001, dated May 24, 2021.
The FAA is adopting a new airworthiness directive (AD) for certain The Boeing Company Model 787-8, 787-9, and 787-10 airplanes. This AD was prompted by a report that during a C-check, corrosion was found in the vertical fin tension bolt hole located in the aluminum crown frames at a certain section. This AD requires inspecting certain vertical fin tension bolt holes; reviewing the bolt sealant application installation procedure in the existing maintenance or inspection program, as applicable; checking maintenance records to determine the replacement status of vertical fin tension bolts; and doing applicable on-condition actions. The FAA is issuing this AD to address the unsafe condition on these products.
Except as specified by paragraph (h) of this AD: At the applicable times specified in the “Compliance” paragraph of Boeing Alert Requirements Bulletin B787-81205-SB550010-00 RB, Issue 001, dated May 24, 2021, do all applicable actions identified in, and in accordance with, the Accomplishment Instructions of Boeing Alert Requirements Bulletin B787-81205-SB550010-00 RB, Issue 001, dated May 24, 2021.
Note 1 to paragraph (g): Guidance for accomplishing the actions required by this AD can be found in Boeing Alert Service Bulletin B787-81205-SB550010-00, Issue 001, dated May 24, 2021, which is referred to in Boeing Alert Requirements Bulletin B787-81205-SB550010-00 RB, Issue 001, dated May 24, 2021.
(1) Where the Compliance Time columns of the tables in the “Compliance” paragraph of Boeing Alert Requirements Bulletin B787-81205-SB550010-00 RB, Issue 001, dated May 24, 2021, use the phrase “the Issue 1 date of Requirements Bulletin B787-81205-SB550010-00 RB,” this AD requires using “the effective date of this AD.”
(2) Where Boeing Alert Requirements Bulletin B787-81205-SB550010-00 RB, Issue 001, dated May 24, 2021, specifies contacting Boeing for repair instructions, this AD requires doing the repair using a method approved in accordance with the procedures specified in paragraph (i) of this AD, except if only finish degradation (no corrosion) is found, this AD requires applying two coats of BMS 10-11, Type 1 primer, as specified in Tasks 2, 4, 6, and 8 of Boeing Alert Requirements Bulletin B787-81205-SB550010-00 RB, Issue 001, dated May 24, 2021.
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.
