Airworthiness Directive · Amendment 39-17205 · Landing gear
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 777-200, -200LR, -300, -300ER, and 777F series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 777-32A0082, dated December 9, 2010.
We are adopting a new airworthiness directive (AD) for certain of The Boeing Company Model 777 airplanes. This AD was prompted by heat damage and cracks at the pivot joint location of the main landing gear (MLG) inner cylinder/truck beam. This AD requires repetitive lubrication of the MLG pivot joints; repetitive detailed inspections of the outer diameter chrome on the center axles of the MLG for chicken- wire cracks, corrosion, and chrome plate distress; repetitive magnetic particle inspections of the outer diameter chrome on the center axles of the MLG for cracks; and related investigative and corrective actions if necessary. We are issuing this AD to detect and correct cracking in the MLG center axle and shock strut inner cylinder lugs (pivot joint), which could result in fracture of the MLG pivot joint components and consequent collapse of the MLG.
At the applicable compliance times specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 777-32A0082, dated December 9, 2010, except as provided by paragraph (i) of this AD: Lubricate the MLG pivot joints; do a detailed inspection of the outer diameter chrome on the center axles of the MLG for chicken-wire cracks, corrosion, and chrome plate distress; do a magnetic particle inspection of the outer diameter chrome on the center axles of the MLG for cracks; and do all applicable related investigative and corrective actions; in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 777-32A0082, dated December 9, 2010, except as provided by paragraph (i)(2) of this AD. Repeat the lubrication and inspections thereafter at the applicable interval specified in paragraph 1.E., “Compliance,” of Boeing Alert Service Bulletin 777-32A0082, dated December 9, 2010. Do all applicable related investigative and corrective actions before further flight.
For the purposes of this AD, chicken-wire cracks are defined as cracks that occur when stress created in the chrome deposit during plating are relieved. The cracks are evident in the deposited chrome when viewed from a perpendicular plane as a pattern similar to chicken wire. Crack size can vary with plating conditions.
(1) Where Boeing Alert Service Bulletin 777-32A0082, dated December 9, 2010, specifies a compliance time after the original issue date of that service bulletin, this AD requires compliance within the specified compliance time after the effective date of this AD.
(2) Where Boeing Alert Service Bulletin 777-32A0082, dated December 9, 2010, specifies use of Royco 11MS grease for the lubrication required by paragraph (g) of this AD, this AD also allows use of MIL-PRF-32014 grease.
(1) Doing the detailed and magnetic particle inspections in accordance with Part 2 of the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0080, dated July 10, 2008; or Boeing Special Attention Service Bulletin 777-32-0080, Revision 1, dated April 16, 2009; is considered acceptable for compliance with the inspections of the center axle of the MLG required by paragraph (g) of this AD.
(2) Accomplishment of all applicable actions specified in and in accordance with the Accomplishment Instructions of Boeing Service Bulletin 777-32-0085, dated April 14, 2011, is considered acceptable for compliance with the requirements of paragraph (g) 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
