In order to prevent adjacent wire harnesses from burning due to breakdown and fire between bare wires, damage the main electrical system, and then burn passengers and crew, in addition to the tasks already completed, the following tasks need to be completed:
A within 30 days after this directive comes into effect, according to the requirements of Boeing's information number. M-7200-98-00140 (1998 65438+1October1,the same below).
1. If the wiring harnesses are not found to be damaged or worn, and there is enough gap between each wiring harness and the adjacent front kitchen air cooler, the work in paragraph A. 1( 1) or A. 1(2) of this manual shall be completed.
(1). Thereafter, whenever the air cooler in the front kitchen is removed and reinstalled, the visual inspection required in paragraph A of this directive shall be repeated, or
(2) Before the next flight, according to the requirements of Chapter 20-00- 1 1 of Boeing Standard Wiring Practices Manual, a protective sleeve or belt should be installed on the wiring harness. Airlines can choose one of the following materials to protect the wire harness: RT876 (sleeve), TFE-2X standard wall thickness (sleeve
2. If the harness is not damaged or worn, but the gap is not enough, before the next flight, the wiring of the harness should be modified according to the requirements of Boeing information bulletin, and the protective sleeve or protective belt should be installed on the harness according to the requirements of Chapter 20-00- 1 1 of Boeing Standard Wiring Practice Manual. Airlines can choose one of the following materials to protect the wiring harness: RT876 (sleeve), TFE-2X standard wall thickness (sleeve), P-440 (belt), Sotch 70 (belt) or CHR-A-2005 (belt).
3. If the wiring harness is found to be damaged or scratched, but the clearance is sufficient, the damaged wiring harness should be repaired according to the requirements of Boeing Information Circular before the next flight, and the work required in paragraph A.3( 1) or paragraph A.3(2) of this directive should be completed:
(1). Thereafter, whenever the air cooler in the front kitchen is removed and reinstalled, the visual inspection required in paragraph A of this directive shall be repeated, or
(2) Before the next flight, install protective cover or protective belt on the wiring harness according to the requirements of Chapter 20-00- 1 1 of Boeing Standard Wiring Practice Manual. Airlines can choose one of the following materials to protect the wiring harness: RT876 (sleeve), TFE-2X standard wall thickness (sleeve), P-440 (belt), Sotch 70 (belt) or CHR-A-2005 (belt).
4. If the harness is found to be damaged or scratched, and the gap is not enough, before the next flight, repair the damaged harness and modify its wiring according to the requirements of Boeing information bulletin, and install protective sleeves or protective belts on the wiring harness according to the requirements of Chapter 20-00- 1 1 of Boeing Standard Wiring Practice Manual. Airlines can choose one of the following materials to protect the wiring harness: RT876 (sleeve), TFE-2X standard wall thickness (sleeve), P-440 (belt), Sotch 70 (belt) or CHR-A-2005 (belt).
B alternative methods that can ensure safety or adjust the completion time can be adopted to complete this instruction, but they must be approved by the airworthiness authority.