EASA Regulations for Robinson Air Crane HH-3

Main Rotor Gearbox - Main Rotor Shaft - Inspection / Replacement

The Federal Aviation Administration's Airworthiness Directive 2026-15-17 is a final rule addressing the main rotor shaft (MRS) inspection and replacement requirements for various helicopter models including Sikorsky S-61 variants, Croman SH-3H, Carson S-61L and SH-3H, Glacier CH-3E, Robinson Air Crane CH-3 and HH-3 variants, and Siller CH-3E and SH-3A helicopters. This directive updates life limits and inspection protocols for MRS part numbers S6135-20640-001, S6135-20640-002, and S6137-23040-001 to ensure continued airworthiness and safety.