R22 SERVICE BULLETIN SB-120C

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Page 1 of 4 R22 SERVICE BULLETIN SB-120C (supersedes R22 Service Bulletin SB-120B) DATE: 22 December 2022 REV C: 28 January 2025 TO: R22-series Owners, Operators, and Maintenance Personnel SUBJECT: Tail Rotor Blade Inspection and Replacement EFFECTIVITY: P/N A029-2 tail rotor blade S/Ns 11279 and prior (A029-2 REV U and prior). Affected blades were factory-installed on R22 Helicopter S/Ns 4873 and prior. Affected blades were also shipped as spares prior to October 2022. TIME OF COMPLIANCE: Part A Inspection: Within next 10 flight hours or by 15 January 2023, whichever occurs first. Recurring inspections are required before the first flight of each day thereafter. Part B Replacement: • For affected tail rotor blades with a geographically unknown operating history: No later than 31 July 2024. • For affected tail rotor blades operating from a sea-going vessel: No later than 31 July 2024 with more than 1 year cumulative operating time, and No later than 02 February 2025 with less than 1 year cumulative operating time. • For affected tail rotor blades operating in a severe-corrosion zone depicted in U.S. FAA Advisory Circular (AC) 43-4B, Corrosion Control for Aircraft, Figures 4-15 thru 4-20, as applicable: No later than 31 July 2024 with more than 3 years cumulative operating time, and No later than 02 February 2025 with less than 3 years cumulative operating time. (OVER) R22 SB-120C Page 2 of 4 TIME OF COMPLIANCE (CONT’D): Part B Replacement (Cont’d): • For affected tail rotor blades with a geographically known operating history not described above: No later than 02 February 2025, or No later than 02 July 2025 under the following conditions: 1. Continue to comply with the [attached] Special Tail Rotor Tip Preflight Inspection insert in the Pilot’s Operating Handbook. 2. Within preceding 15 days, ensure compliance with 10X visual inspection described in the AMOC dated 23 January 2025 to AD 2024-04-02. Note that this inspection is not considered preventive maintenance and may only be performed by personnel authorized by 14 CFR 43.7. BACKGROUND: RHC has received additional reports of tail rotor blade tips coming loose due to corrosion at the bond. Helicopters operating near saltwater are particularly susceptible to corrosion, especially if stored outdoors. A debonded tip can cause severe vibration and possible failure of the tail rotor gearbox housing. A029-2 revision V blades have tip caps with an alternate alloy to reduce the likelihood of corrosion. Revision C of this bulletin aligns the requirements of this bulletin with AMOC approved in FAA letter 772-25-00024 dated 23 January 2025 to U.S. FAA Airworthiness Directive 2024-04-02. COMPLIANCE PROCEDURE: PART A: If helicopter is equipped with affected tail rotor blades, insert enclosed Special Tail Rotor Tip Preflight Inspection (page 3 of this bulletin) before the title page of the Pilot’s Operating Handbook. NOTE: Copies of Special Tail Rotor Tip Preflight Inspection sheet should also be made available to mechanics. Sheet may be removed from Pilot’s Operating Handbook following replacement of affected tail rotor blades. PART B: Replace each affected tail rotor blade per R22 Maintenance Manual (MM) § 28-20 and install tail rotor assembly per MM § 28-10. Enter new blade serial numbers in aircraft maintenance records. NOTE: MT179-4 shaft is required to accomplish tail rotor static balance. Available from RHC Customer Service if not already on hand. (Also, refer to R22 SL-96 Tail Rotor Static Balance Equivalent Tool.) APPROXIMATE COST: Part A: Parts: None required (Special Tail Rotor Tip Preflight Inspection sheet included as part of Bulletin). Labor: 0.2 labor-hour. Part B: Parts: No charge for helicopters or parts under warranty; each legible data plate removed from an affected blade and returned to RHC will be exchanged for a new blade. Blades beyond warranty period will be discounted to $1020 provided: a. Blade is in airworthy condition. RHC must receive legible data plate and either photographic evidence of blade condition or actual blade. b. Blade has not exceeded its 12 year calendar life. c. Blade is not within 100 hours of its life limit. Discount only applies to blades replaced by July 2025. Cost does not include transportation. Normal Service Center discounts do not apply (see Dealer/Service Center Memo dated May 28, 1997). Labor: 3.5 labor-hours. R22 SB-120C Page 3 of 4 THE DESIGN ENGINEERING ASPECTS OF THIS BULLETIN HAVE BEEN SHOWN TO COMPLY WITH APPLICABLE FEDERAL AVIATION REGULATIONS AND ARE FAA APPROVED. This page intentionally blank. R22 SB-120C Page 4 of 4 (This page to be printed on yellow paper.) Cut or fold along this line R22 SB-120C SPECIAL TAIL ROTOR TIP PREFLIGHT INSPECTION To be inserted before the title page of the Pilot’s Operating Handbook for all helicopters with affected tail rotor blades per R22 SB-120C. Brief all pilots and maintenance personnel regarding these inspection requirements. Date: 22 December 2022 Refer to Figure below. To be performed before the first flight of each day. May be performed by pilot or mechanic. Conduct visual inspection of tail rotor tip area. If bubbled paint or other evidence of corrosion is observed at or adjacent to tip cap bond line or if any portion of tip cap bond line is exposed, do not fly helicopter. Comply with latest revision of R22 SL-93 prior to further flight. This page may be removed from the Pilot’s Operating Handbook following replacement of affected tail rotor blades.