AD 2026-11-05 Airworthiness Directives; Various Helicopters

Models named: S-61L, SH-3H, CH-3E, USAF CH-3C, HH-3C, HH-3E, S-61A, S-61D, S-61E, S-61V. Read the applicability below — it usually turns on serial or part numbers too.

This AD applies to the helicopters identified in paragraphs (c)(1) through (7) of this AD, certificated in any category. (1) Carson Helicopters, Inc. Model S-61L and SH-3H helicopters. (2) Croman Corporation Model SH-3H helicopters. (3) Glacier Helicopter, Inc. Model CH-3E helicopters. (4) Reynolds Aviation Model USAF CH-3C, CH-3E, HH-3C, and HH-3E helicopters. (5) Sikorsky Aircraft Corporation Model S-61A, S-61D, S-61E, and S-61V helicopters. (6) Sikorsky Aircraft Model S-61L, S-61N, S-61NM, and S-61R helicopters. (7) Siller Helicopters Model CH-3E and SH-3A helicopters.

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

As of the effective date of this AD, before the first flight of each day, inspect the lockwire to determine if attachment hardware does not rotate under finger pressure, and use a high-powered light source and mirror to perform a visual inspection of the auxiliary servo assembly located in the controls compartment (also known as the broom closet) for hydraulic fluid leakage, cracks, missing or loose lockwire, and compromised bolt security (loose, missing, cracked, fractured, or stretched bolts) in accordance with the Accomplishment Instructions Section 3.C.(3)(a) and (b) of Sikorsky Aircraft Corporation S-61 Helicopter Alert Service Bulletin ASB 61B65-25, Basic Issue, dated October 17, 2022, as corrected by Sikorsky Aircraft Corporation S-61 Helicopter Alert Service Bulletin Errata, effective February 3, 2026 (Sikorsky ASB 61B65-25). (1) If there is any hydraulic fluid leakage, compromised bolt security (loose, missing, cracked, fractured, or stretched bolts), or if there are any cracks on the yaw pedal damper check valve housing, before further flight, replace the yaw pedal damper check valve housing and the associated attachment bolts with serviceable parts. (2) If there is any loose or missing lockwire, before further flight, inspect that each bolt has a torque value of 45-50 in./lbs. and perform the applicable corrective actions as follows. (i) If the torque value is correct replace the lockwire. (ii) If the torque value is below 45 in./lbs. or above 50 in./lbs., or if evidence of compromised bolt security (loose, missing, cracked, fractured, or stretched bolts) is found, replace the yaw pedal damper check valve housing, the associated attachment bolts, and lockwire with serviceable parts.

This AD was prompted by a report of a loss of tail rotor authority due to auxiliary system fluid loss caused by a yaw pedal damper housing fatigue fracture and attachment bolt fatigue fracture. The FAA is issuing this AD to detect and address cracking of the yaw pedal damper housing and attachment bolts and a non-conforming lug radius on the yaw pedal damper housing. The unsafe condition, if not addressed, could result in auxiliary system fluid loss, loss of tail rotor authority, and consequent reduced controllability of the helicopter or loss of control of the helicopter.

None.