Airworthiness Directive · Amendment 39-16541 · Stabilizers
Pacific Aerospace Limited Model FU24-954 and FU24A-954 Airplanes
This AD applies to Pacific Aerospace Limited FU24-954 and FU24A-954 airplanes, all serial numbers, certificated in any category.
We are superseding an existing airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) issued by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:
For airplanes that have not been modified by installation of vertical stabilizer part number (P/N) 08-32005-2, do the following actions:
(1) As of August 21, 2008 (the effective date retained from AD 2008-14-12), before the first flight of each day, visually inspect the vertical stabilizer leading edge skin and fin for any cracking, corrosion, scratches, dents, creases, and/or buckling and repair as necessary. All non-transparent protective coatings and their adhesive must be removed for this inspection.
(2) Within 100 hours time-in-service (TIS) after August 21, 2008 (the effective date retained from AD 2008-14-12), and repetitively thereafter at intervals not to exceed 100 hours TIS, perform a detailed inspection of the vertical stabilizer leading edge skin, leading edge, fin skin, and the fin forward attachment point for any cracking, corrosion, scratches, dents, creases, and/or buckling to include:
(i) Inspection of the entire leading edge down to the forward attach fitting and removal of dorsal fin extensions, if installed, to inspect the obscured areas of the fin.
(ii) Inspection of the fin skin for corrosion and cracks, paying particular attention to the center rib rivet holes and the skin joint at the fin base.
(iii) Inspection of the fin forward attachment point for corrosion, removal of the fin tip, and inspection of the top rib for cracks at the skin stiffener cut outs.
(3) If any damage is found during any inspection required in paragraph (f)(1) or (f)(2) of this AD, before further flight, obtain an FAA-approved repair scheme from the manufacturer and incorporate that repair. Contact the manufacturer for the repair scheme by one of the methods listed in the Related Information section of this AD.
(4) The following transparent polyurethane protective tapes have been assessed as suitable for use to re-protect the leading edge and may remain in situ for subsequent inspections, provided they are sound and in a condition to permit visual inspection of the skin beneath them:
| Manufacturer | Product |
|---|---|
| (i) 3M | 8591, or 8671, 8672 and 8681HS (aeronautical grade) |
| (ii) Scapa | Aeroshield P2604 (transparent) |
Note 1: You may apply for an alternative method of compliance (AMOC) for an alternative to the transparent polyurethane protective tapes listed above.
(5) Within 6 months after January 20, 2011 (the effective date of this AD), replace the vertical stabilizer with P/N 08-32005-2 following Pacific Aerospace Limited Mandatory Service Bulletin PACSB/FU/094, Issue 1, dated August 14, 2008. Installation of vertical stabilizer P/N 08-32005-2 terminates the repetitive inspection requirements of paragraphs (f)(1) and (f)(2) of this AD.
(g) For airplanes that have been modified by installation of vertical stabilizer P/N 08-32005-2, do the following actions:
(1) Within 300 hours TIS after installation of vertical stabilizer P/N 08-32005-2 or within 50 hours TIS after January 20, 2011 (the effective date of this AD), whichever occurs later, and repetitively thereafter at intervals not to exceed 300 hours TIS, do a detailed visual inspection of the vertical stabilizer following paragraph 2.B.i) of Pacific Aerospace Limited Mandatory Service Bulletin PACSB/FU/094, Issue 1, dated August 14, 2008.
(2) Within 3,000 hours TIS after installation of vertical stabilizer P/N 08-32005-2 or within 50 hours TIS after January 20, 2011 (the effective date of this AD), whichever occurs later, and repetitively thereafter at intervals not to exceed 3,000 hours TIS, do an eddy current inspection following paragraph 2.B.ii) of Pacific Aerospace Limited Mandatory Service Bulletin PACSB/FU/094, Issue 1, dated August 14, 2008.
Note 2: This AD differs from the MCAI and/or service information as follows: (1) The inspections required in paragraph (f)(1) of this AD must be performed by a person authorized under 14 CFR part 43 to perform inspections, as opposed to the MCAI, which allows the holder of a pilot license to perform the inspections. (2) The 50-hour inspection required in the MCAI is not applicable because the “before the first flight of the day” inspection captures the intent. (3) The MCAI does not require the inspections listed in Pacific Aerospace Limited Mandatory Service Bulletin PACSB/FU/094, Issue 1, dated August 14, 2008. To require compliance with these inspections for U.S. owners and operators we are requiring the inspections through this AD action.
