Airworthiness Directive · Amendment 39-17088 · Main landing gear
The Boeing Company Airplanes
Superseded. A later AD replaced this one: AD 2014-05-09. Comply with the one in force.
This AD applies to The Boeing Company Model 777-200 and -S300 series airplanes; certificated in any category; as identified in Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011.
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 777-200 and -300 series airplanes. This AD was prompted by reports of cracked retract actuator fuse pins that can fail earlier than the previously determined safe life limit of the pins. A fractured retract actuator fuse pin can cause the main landing gear to extend without restriction and attempt to lock into position under high dynamic loads. This AD requires an inspection for the part number of the fuse pin, and replacement of the pin if necessary. We are issuing this AD to prevent structural damage to the side and drag brace lock assemblies, which could result in landing gear collapse during touchdown, rollout, or taxi.
Within 18 months after the effective date of this AD: Inspect the part number of the fuse pins of the left and right MLG retract actuators, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011. A review of airplane maintenance records is acceptable in lieu of this inspection if the part number of the installed actuator fuse pin can be conclusively determined from that review.
(1) If any retract actuator fuse pin having part number 112W1769-3 is found installed, no further action is required by this paragraph for that fuse pin.
(2) If any retract actuator fuse pin having part number 112W1769-1 is found installed and the pin has accumulated more than 10,000 total flight cycles as of the effective date of this AD: Within 18 months after the effective date of this AD, replace the fuse pin with a new part number 112W1769-3 fuse pin, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011.
(3) If any retract actuator fuse pin having part number 112W1769-1 is found installed and the pin has accumulated 8,000 or more total flight cycles, but fewer than or equal to 10,000 total flight cycles, as of the effective date of this AD: Before the accumulation of 10,000 total flight cycles on the pin, or within 18 months after the effective date of this AD, whichever occurs later, replace the fuse pin with a new part number 112W1769-3 fuse pin, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011.
(4) If any retract actuator fuse pin having part number 112W1769-1 is found installed and the pin has accumulated fewer than 8,000 total flight cycles as of the effective date of this AD: Before the accumulation of 8,000 total flight cycles on the pin, or within 24 months after the effective date of this AD, whichever occurs later, replace the fuse pin with a new part number 112W1769-3 fuse pin, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011.
As of the effective date of this AD, no person may install a retract actuator fuse pin having part number 112W1769-1 on any airplane.
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
