AD 2024-01-11 Airworthiness Directives; Various Helicopters

This AD applies to all helicopters, certified in any category, with a restraint system with a Pacific Scientific Company rotary buckle assembly (buckle) part number (P/N) 1111475 (all dash numbers) or P/N 1111548-01 installed having a date of manufacture between January 2012 and September 2012 inclusive or an unknown date of manufacture. These buckles may be installed on, but not limited to, Airbus Helicopters model helicopters, certificated in any category.

Comply with this AD within the compliance times specified, unless already done.

(1) For helicopters with buckle P/N 1111475 (all dash numbers), within 3 months after the effective date of this AD, inspect each buckle screw for cracked, loose, and missing screw heads by following the Accomplishment Instructions, paragraphs B.(1) and (2), of Parker Meggitt Service Bulletin (SB) 1111475-25-001-2023, Revision 001, dated December 1, 2023 (SB 1111475-25-001-2023 Rev 001). (i) If any screw has a cracked, loose, or missing screw head, before further flight, replace the buckle with an airworthy buckle. (ii) If none of the four screw heads are cracked, loose, or missing, before further flight, inspect each screw to determine if any screw has a Torx head by using one of the following methods in the Accomplishment Instructions of SB 1111475-25-001-2023 Rev 001: paragraph B.(4)(a) (Magnet Test); paragraph B.(4)(b) (Inspection); or paragraphs C.(2) through (4) (removing the buckle from the restraint system) and paragraphs D.(1)(a) through (d) (disassembling the buckle). Note 1 to paragraph (g)(1): SB 1111475-25-001-2023 Rev 001 refers to a magnifying glass as an “eye loupe.” (A) If none of the four screws have a Torx head, before further flight, reassemble the buckle (if necessary) by following the Accomplishment Instructions, paragraphs D.(1)(f) through (l), of SB 1111475-25-001-2023 Rev 001, and reidentify the buckle with “INS. A” by following the Accomplishment Instructions, paragraph B.(6), of SB 1111475-25-001-2023 Rev 001. (B) If at least one of the four screws has a Torx head, before further flight, with the buckle removed, replace each Torx head screw with a hex head screw, reassemble the buckle, and reidentify the buckle with “MOD. A” by following the Accomplishment Instructions, paragraphs D.(1)(e) through (m), of SB 1111475-25-001-2023 Rev 001, except you are not required to return any parts to Parker Meggitt. If a screw head breaks off during disassembly, before further flight, replace the buckle with an airworthy buckle. (2) For helicopters with buckle P/N 1111548-01, within 3 months after the effective date of this AD, inspect each buckle screw for cracked, loose, and missing screw heads by following the Accomplishment Instructions, paragraph B.(1), of Parker Meggitt SB 1111548-25-001-2023, Revision 001, dated December 1, 2023 (SB 1111548-25-001-2023 Rev 001). (i) If any screw has a cracked, loose, or missing screw head, before further flight, replace the buckle with an airworthy buckle. (ii) If none of the four screw heads are cracked, loose, or missing, before further flight, inspect each screw to determine which screws have a Torx head by using one of the following methods in the Accomplishment Instructions of SB 1111548-25-001-2023 Rev 001: paragraph B.(3)(a) (except use Figure 6 for placement of the shim tool and use Figure 5 to distinguish the screw head types) (Inspection); or paragraph C. (removing the buckle from the restraint system) and paragraphs D.(1)(a) through (c) (disassembling the buckle). Before further flight, with the buckle removed, replace each Torx head screw with a hex head screw, reassemble the buckle, and reidentify the buckle with “MOD. A” by following the Accomplishment Instructions, paragraphs D.(1)(d) through (m), of SB 1111548-25-001-2023 Rev 001, except you are not required to return any parts to Parker Meggitt. If a screw head breaks off during disassembly, before further flight, replace the buckle with an airworthy buckle. Note 2 to paragraph (g)(2): SB 1111548-25-001-2023 Rev 001 refers to a magnifying glass as an “eye loupe.” (3) As of the effective date of this AD, do not install a buckle identified in paragraph (c) of this AD on any helicopter unless the buckle is marked with “MOD. A” or “INS. A”.

This AD was prompted by a report of a manufacturing defect in the screws used inside the buckle. The FAA is issuing this AD to prevent cracking and missing screw heads when under load. The unsafe condition, if not addressed, could result in a failure of the buckle to restrain the occupant.

None.