Airworthiness Directive · Amendment 39-17226 · Flight controls
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 777-200LR and -300ER series airplanes, certificated in any category, identified in Boeing Alert Service Bulletin 777-27A0109, dated December 1, 2011.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 777-200LR and -300ER series airplanes. This AD requires reviewing the airplane's maintenance records for each rudder power control unit (PCU) to identify the condition of its related reaction link assembly, and replacing the rudder PCU and its related reaction link assembly if necessary. This AD was prompted by a report of an abnormal airframe vibration in the aft fuselage during flight. We are issuing this AD to prevent excessive freeplay in the rudder control surface, which could cause rudder vibration, and result in structural damage severe enough to prevent continued safe flight and landing.
Within 48 months after the effective date of this AD, review the airplane's maintenance records for each rudder power control unit (PCU) to identify the condition of its related reaction link assembly, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777-27A0109, dated December 1, 2011.
(1) For any reaction link assembly identified during the records review required by paragraph (g) of this AD as having Condition 4, as specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 777-27A0109, dated December 1, 2011: Within 48 months after the effective date of this AD, remove the affected rudder PCU and its related reaction link assembly, and install a serviceable rudder PCU and its related reaction link assembly, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777-27A0109, dated December 1, 2011.
(2) The replacement PCU reaction link assembly must meet Condition 1, 2, or 3 of Part 1 of the Accomplishment Instructions of Boeing Alert Service Bulletin 777-27A0109, dated December 1, 2011. As an alternative, the bushings in the PCU reaction link assembly may be replaced in accordance with Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 777-27A0109, dated December 1, 2011.
As of the effective date of this AD, no person may install a rudder PCU and its related reaction link assembly identified in Boeing Alert Service Bulletin 777-27A0109, dated December 1, 2011, on any airplane, unless that rudder PCU and its related reaction link assembly meet Condition 1, 2, or 3, of Part 1 of the Accomplishment Instructions of Boeing Alert Service Bulletin 777-27A0109, dated December 1, 2011.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
Aircraft
