Airworthiness Directive · Amendment 39-18703 · Hydraulic power
The Boeing Company Airplanes
This AD applies to The Boeing Company Model 737-600, 737-700, 737-700C, 737-800, 737-900, and 737-900ER series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 737-29A1119, Revision 1, dated June 23, 2016 (“ASB 737-29A1119 R1”).
We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 737-600, -700, -700C, -800, -900, and -900ER series airplanes. This AD was prompted by a report of wire chafing damage, which caused an electrical arc to an adjacent hydraulic tube located on the forward bulkhead of the main landing gear (MLG) wheel well, resulting in a hole in a hydraulic tube and consequent total loss of system B hydraulic fluid. This AD requires an inspection for chafing damage of wire bundles and a hydraulic tube in the right side of the MLG wheel well, and corrective action if necessary; and installation of clamps between the wire bundles and hydraulic tube. We are issuing this AD to prevent chafing damage, which could result in electrical arcing that can cause a hole in the hydraulic tube and consequent loss of hydraulic fluid, possibly resulting in a fire in the MLG wheel well.
Within 24 months after the effective date of this AD: Do the actions specified in paragraphs (g)(1) and (g)(2) of this AD.
(1) Do a detailed inspection for chafing damage of the wire bundles and hydraulic tube in the right side of the MLG wheel well, and do all applicable corrective actions, in accordance with the Accomplishment Instructions of ASB 737-29A1119 R1. Do all applicable corrective actions before further flight.
(2) Install new clamps and an optional spacer between the wire bundles and hydraulic tube in the right side of the MLG wheel well, in accordance with the Accomplishment Instructions of ASB 737-29A1119 R1.
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.
