Airworthiness Directive · Amendment 39-16139 · Landing gear
Boeing Model 737-600, -700, -700C, -800, and -900 Series Airplanes
This AD applies to Boeing Model 737-600, -700, -700C, -800, and -900 series airplanes, certificated in any category, as identified in Boeing Service Bulletin 737-32-1376, Revision 2, dated August 6, 2008.
The FAA is adopting a new airworthiness directive (AD) for certain Boeing Model 737-600, -700, -700C, -800, and -900 series airplanes. This AD requires repetitive lubrication of the left and right main landing gear (MLG) forward trunnion pins; and an inspection for discrepancies of the transition radius, lead-in chamfer, and cross- bolt bore of the MLG forward trunnion pins, and repair or replacement if necessary. Doing the applicable inspections and repairs/ replacements, or overhauling the trunnion pins ends the repetitive lubrication requirements of this AD. For airplanes on which a certain repair is done, this AD requires repetitive inspections for discrepancies of the transition radius. This AD results from a report that the protective finishes on the forward trunnion pins for the left and right MLG might have been damaged during final assembly. We are issuing this AD to prevent cracking of the forward trunnion pin, which could result in fracture of the pin and consequent collapse of the MLG.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
Within 30 days after the effective date of this AD: Lubricate the left and right MLG forward trunnion pins in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-32-1376, Revision 2, dated August 6, 2008. Repeat the lubrication at intervals not to exceed 30 days until all applicable requirements of paragraphs (h) and (i) of this AD have been accomplished. Overhauling the trunnion pin in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-32-1376, Revision 2, dated August 6, 2008, ends the repetitive lubrication requirements of this paragraph for that pin.
Within 60 months after the date of issuance of the original airworthiness certificate or date of issuance of the original export certificate of airworthiness, or within 6 months after the effective date of this AD, whichever occurs later: Do a detailed inspection for discrepancies (corrosion, finish damage, surface deformation, or scratches) of the transition radius of the left and right MLG trunnion pins with MLG not removed (in situ); and if any discrepancy is found, repair or replace the trunnion pin before further flight. Do all actions in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-32-1376, Revision 2, dated August 6, 2008. If the repair specified in Part 4 of the Accomplishment Instructions of Boeing Service Bulletin 737-32-1376, Revision 2, dated August 6, 2008, is done, within 24 months after doing the repair, do the detailed inspection of the transition radius, and do the inspection thereafter at intervals not to exceed 24 months until the trunnion pin is overhauled or replaced in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-32-1376, Revision 2, dated August 6, 2008.
(i) For airplanes on which the trunnion pin has not been replaced or overhauled: Within 120 months after the date of issuance of the original airworthiness certificate or date of issuance of the original export certificate of airworthiness, or within 6 months after the effective date of this AD, whichever occurs later, do a detailed inspection for discrepancies of the lead-in chamfer and cross-bolt bore with the MLG removed; and if any discrepancy is found, repair or replace the trunnion pin before further flight. Do all actions in accordance with the Accomplishment Instructions of Boeing Service Bulletin 737-32-1376, Revision 2, dated August 6, 2008.
Although Boeing Service Bulletin 737-32-1376, Revision 2, dated August 6, 2008, specifies to send inspection reports to the manufacturer, this AD does not include that requirement.
Actions done before the effective date of this AD in accordance with Boeing Special Attention Service Bulletin 737-32-1376, dated May 12, 2005; or Boeing Service Bulletin 737-32-1376, Revision 1, dated March 19, 2007; are acceptable for compliance with the corresponding actions of this AD.
