Airworthiness Directive · Amendment 39-17627 · Flight controls
the Boeing Company Airplanes
This AD applies to the Boeing Company Model 747-8F and 747-8 series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 747-27A2515, dated August 23, 2013.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 747-8F and 747-8 series airplanes. This AD requires a detailed inspection of the power control actuator (PCA) installation to determine if a bushing is installed, a general visual inspection between the horizontal stabilizer rear spar and the elevator front spar and between certain stabilizer stations for defects and damage, and corrective actions if necessary. This AD was prompted by a report of unusual noise coming from the left inboard elevator during a functional check of the ram air turbine system, and a determination that a bushing was not installed. We are issuing this AD to detect and correct non-installation of bushings. If the bushings are not present, the stiffness of the load path will be decreased, which will cause wear of adjacent parts and increased freeplay of the elevator surfaces. Freeplay that exceeds acceptable limits could result in divergent flutter for certain maneuvers, which could lead to loss of controllability of the airplane.
Except as required by paragraph (h)(1) of this AD, at the time specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 747-27A2515, dated August 23, 2013: Do a detailed inspection of the inboard elevator left and right power control actuator (PCA) installations to determine if a bushing is installed; and do a general visual inspection between the left and right horizontal stabilizer rear spar and the elevator front spar, and between stabilizer station (STAB) (STA) 235 and 260 for defects and damage, and do all applicable corrective actions that are labeled as “RC” (Required for Compliance), in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 747-27A2515, dated August 23, 2013, except as required by paragraph (h)(2) of this AD. Doing the steps specified in Parts 1 and 2 of the Accomplishment Instructions of Boeing Alert Service Bulletin 747-27A2515, dated August 23, 2013, are required for compliance. Do all applicable corrective actions that are labeled as “RC” before further flight.
(1) Where Boeing Alert Service Bulletin 747-27A2515, dated August 23, 2013, specifies a compliance time “after the original issue date of this service bulletin,” this AD requires compliance within the specified compliance time after the effective date of this AD.
(2) Although Boeing Alert Service Bulletin 747-27A2515, dated August 23, 2013, specifies to contact Boeing for repair instructions, and indicates that action is “RC” (Required for Compliance), this AD requires repairing before further flight using a method approved in accordance with the procedures specified in paragraph (i) of this AD.
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
