Airworthiness Directive · Amendment 39-15384 · Boeing Model 767-200, -300, -300F, and -400ER Series Airplanes
Boeing Model 767-200, -300, -300F, and -400ER Series Airplanes
This AD applies to Boeing Model 767-200, -300, -300F, and -400ER series airplanes, certificated in any category, as identified in Boeing Alert Service Bulletin 767-24A0162, dated May 30, 2006.
The FAA is superseding an existing airworthiness directive (AD), which applies to certain Boeing Model 767-200, -300, and -300F series airplanes. That AD currently requires reworking the surface of the ground stud bracket of the left and right transformer rectifier units (TRUs) and the airplane structure mounting surface, and measuring the resistance from the bracket to the structure and the ground lugs to the bracket using a bonding meter. This new AD revises the applicability of the existing AD to include additional airplanes and requires, among other actions, installation of a new ground stud bracket using faying surface bonding. This AD results from a report of loss of all direct current (DC) power generation during a flight, due to inadequate electrical ground path between the ground bracket of the TRUs/main battery charger (MBC) and the structure. We are issuing this AD to prevent depletion of the main battery while in flight, resulting from the loss of both TRUs and the MBC, and consequent loss of all DC power, which could impact the safe flight and landing of the airplane due to the loss of function or malfunction of essential/critical systems and displays in the cockpit.
You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.
For Model 767-200, -300, and -300F series airplanes, as listed in Boeing Alert Service Bulletin 767-24A0119, Revision 2, dated August 19, 2004; on which the actions of Boeing Service Bulletin 767-24-0119, dated May 14, 1998, and/or Revision 1, dated December 16, 1999, have been done: Within 45 days after December 1, 2004 (the effective date of AD 2004-23-14), rework the ground stud bracket of the TRUs and structure mounting surface, and measure the resistance from the bracket to the structure and the grounding lug to the bracket using a bonding meter, in accordance with the Accomplishment Instructions of Boeing Alert Service Bulletin 767-24A0119, Revision 2, dated August 19, 2004, as revised by Boeing Information Notice 767-24A0119 IN 01, dated October 21, 2004, except as provided by paragraph (g) of this AD.
(g) Step 4, Sheet 3 of Figure 1 in the Accomplishment Instructions of the service bulletin only specifies to install one collar with part number (P/N) BACC30M6. However, a collar with P/N BACC30BL6 (as listed in paragraph 2.C., “Parts Necessary For Each Airplane” of the service bulletin) may be used as an alternative method of compliance (AMOC).
For all airplanes: Within 36 months after the effective date of this AD, rework the existing ground stud bracket of the TRUs/MBC, measure the resistance, and install a new ground stud bracket of the TRUs by doing all the applicable actions specified in the Accomplishment Instructions of Boeing Alert Service Bulletin 767-24A0162, dated May 30, 2006.
