Robinson issues service letters for R66, R44, and R22 The OEM has published a safety notice for R22, R44, and R66 owners and operators on the topic of main-rotor blade leading edge refinishing, as well as a notice for R44 and R66 operators related to the pitch-link assembly. R22 SL-102, R44 SL-94, R66 SL-53: “Main Rotor Blade Leading Edge Refinishing R44 SL-95, R66 SL-54: “C258-8 Pitch Link Assembly
