AD 2003-03-09

Applicability: Model MD-90-30 airplanes as listed in McDonnell Douglas Alert Service Bulletin MD90-24A053, Revision 01, dated February 23, 2001; certificated in any category.

Note 1:

This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent failure of a remote control circuit breaker (RCCB) to trip during an overload condition due to a defective braze joint in the RCCB latch assembly, which could result in overheating of the RCCB load wire, and consequent smoke and possible fire in the electrical/electronic (E/E) compartment of the airplane, accomplish the following:

(a) Within 6 months after the effective date of this AD, perform a one-time inspection of the single-phase RCCB or RCCBs, as applicable, at station Y=120.050 in the E/E compartment of the airplane to determine the part number and serial number of the RCCB(s), per the Accomplishment Instructions of McDonnell Douglas Alert Service Bulletin MD90-24A053, Revision 01, excluding Evaluation Form, dated February 23, 2001.

(1) If an RCCB has a part number that is not listed in Table 1, Figure 1, or Table 2, Figure 2, of the service bulletin, as applicable: No further action is required by this AD for that RCCB. It is not necessary to report findings to Boeing by completing the form in the Appendix of the service bulletin.

(2) If an RCCB has a part number that is listed in Table 1, Figure 1, or Table 2, Figure 2, of the service bulletin, as applicable, and the corresponding serial number is not identified in that table: No further action is required by this AD for that RCCB. It is not necessary to report findings to Boeing by completing the form in the Appendix of the service bulletin.

(3) If an RCCB has a part number that is listed in Table 1, Figure 1, or Table 2, Figure 2, of the service bulletin, as applicable; and the corresponding serial number is identified in that table: Before further flight, replace the RCCB with a new or serviceable RCCB per the Accomplishment Instructions of the service bulletin. The replacement RCCB must have the same part number as the part being replaced, and a serial number that is not identified in Table 1, Figure 1, or Table 2, Figure 2, of the service bulletin, as applicable. It is not necessary to report findings to Boeing by completing the form in the Appendix of the service bulletin.

(b) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Los Angeles ACO.

Note 2:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Los Angeles ACO.

(c) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

(d) The actions shall be done in accordance with McDonnell Douglas Alert Service Bulletin MD90-24A053, Revision 01, excluding Evaluation Form, dated February 23, 2001. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Boeing Commercial Aircraft Group, Long Beach Division, 3855 Lakewood Boulevard, Long Beach, California 90846, Attention: Data and Service Management, Dept. C1-L5A (D800-0024). Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; at the FAA, Los Angeles Aircraft Certification Office, 3960 Paramount Boulevard, Lakewood, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(e) This amendment becomes effective on March 7, 2003.