EASA SIB AIR-21-11: Rotorcraft Servo System - Pre-Take-Off Check

What to do

Owners and operators of Robinson Model R44, R44 II, and R66 helicopters with hydraulic servos manufactured before April 2014 should perform the pre-takeoff check procedures outlined in Robinson Service Bulletins SB-109 and SB-39 dated June 30, 2021. No compliance deadline is mandated, but adherence to these recommendations is advised to ensure safe operation.

Summary

The Special Airworthiness Information Bulletin SAIB: AIR-21-11 is an FAA informational bulletin addressing the rotorcraft servo system on Robinson Helicopter Company Model R66, R44, and R44 II helicopters equipped with D212-1, D212-5, and D212-6 hydraulic servos manufactured before April 2014. It highlights a potential issue with servo wear that can cause stiff cyclic controls during flight. This bulletin is not a mandatory directive but provides important safety information for operators of these specific Robinson helicopter models.

What changed

SAIB AIR-21-11 introduces awareness of internal wear issues in hydraulic servos on certain Robinson R66, R44, and R44 II helicopters that may cause stiff cyclic controls. It recommends performing a specific pre-takeoff check as detailed in Robinson Service Bulletins SB-109 for R44 and SB-39 for R66, both dated June 30, 2021. This bulletin does not impose new regulatory requirements but advises operators on preventive measures.

Why it matters

This bulletin matters because it informs operators and maintenance personnel of a potential control stiffness issue that could affect flight safety during critical phases such as landing. Early detection through the recommended pre-takeoff check can prevent control difficulties and enhance operational safety. It also helps maintenance teams identify servo wear before it leads to more serious control problems.

What to do

Summary

What changed

Why it matters

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