AD 2004-07-12 Airworthiness Directives; McDonnell Douglas Model MD-90-30 Airplanes

Models named: MD-90-30. Read the applicability below — it usually turns on serial or part numbers too.

Model MD-90-30 airplanes, as listed in McDonnell Douglas Alert Service Bulletin MD90-24A031, Revision 01, dated February 28, 2001, or McDonnell Douglas Alert Service Bulletin MD90-24A043, Revision 01, dated March 12, 2001; certificated in any category.

Required as indicated, unless accomplished previously. To prevent overheating of the terminal studs on the 3-phase limiter blocks and associated current limiters, which could cause a fire in the airplane, accomplish the following: Inspection and Replacement (a) For those airplanes listed as Group 1 airplanes in McDonnell Douglas Alert Service Bulletin MD90-24A043, Revision 01, dated March 12, 2001, which are also listed in McDonnell Douglas Alert Service Bulletin MD90-24A031, Revision 01, dated February 28, 2001: Within 6 months after the effective date of this AD, accomplish the following actions: (1) Inspect the 3 spare current limiters located in the electrical power center (EPC) in accordance with the Accomplishment Instructions of McDonnell Douglas Alert Service Bulletin MD90-24A043, Revision 01, dated March 12, 2001. If the inspection reveals that any of the current limiters located in the electrical power unit are defective, before further flight replace the defective current limiter(s) with new current limiter(s) in accordance with the alert service bulletin. (2) Prior to or concurrent with accomplishment of paragraph (a)(1) of this AD, accomplish the following actions in accordance with McDonnell Douglas Alert Service Bulletin MD90-24A031, Revision 01, dated February 28, 2001: (i) Replace the 3-phase limiter block assembly and associated clear cover of the EPC with a serialized 3-phase limiter block assembly and a new clear cover. (ii) Replace the 6 current limiters and attaching parts on the limiter block with new current limiters and attaching parts. (iii) Replace hardware for 9 electrical cables attached to the limiter block with new attaching hardware. Replacement (b) For those airplanes listed in McDonnell Douglas Alert Service Bulletin MD90-24A031, Revision 01, dated February 28, 2001: Within 6 months after the effective date of this AD, accomplish the following actions in accordance with the Accomplishment Instructions of the alert service bulletin: (1) Replace the 3-phase limiter block assembly and associated clear cover of the EPC with a serialized 3-phase limiter block assembly and a new clear cover. (2) Replace the 6 current limiters and attaching parts on the limiter block with new current limiters and attaching parts. (3) Replace hardware for 9 electrical cables attached to the limiter block with new attaching hardware. Other Inspection (c) For those airplanes listed as Group 2 airplanes in McDonnell Douglas Alert Service Bulletin MD90-24A043, Revision 01, dated March 12, 2001: Within 6 months after the effective date of this AD, accomplish the following actions in accordance with the Accomplishment Instructions of the alert service bulletin. (1) Inspect the 6 current limiters and attaching hardware on the 3-phase limiter blocks and the 3 spare current limiters located in the EPC to determine whether any of the current limiters are defective. (2) If the inspection required by paragraph (c)(1) of this AD reveals that any of the current limiters are defective, before further flight replace the defective current limiters with new current limiters, in accordance with Figure 1 of the Accomplishment Instructions. Parts Installation (d) As of the effective date of this AD, no person shall install on any airplane a Tri-Star 3-phase limiter block assembly having part number (P/N) C-1301-3 or a Burndy 3-phase limiter block assembly having P/N F6H-2, unless that 3-phase limiter block assembly has serial number 3015 or higher. Information Submission (e) Although McDonnell Douglas Alert Service Bulletin MD90-24A031, Revision 01, dated February 28, 2001, referenced in this AD specifies that certain information is to be submitted to the airplane manufacturer, this AD does not include such a requirement. Alternative Methods of Compliance (f) In accordance with 14 CFR 39.19, the Manager, Los Angeles Aircraft Certification Office, FAA, is authorized to approve alternative methods of compliance (AMOCs) for this AD. Incorporation by Reference (g) The actions shall be done in accordance with McDonnell Douglas Alert Service Bulletin MD90-24A043, Revision 01, dated March 12, 2001; and McDonnell Douglas Alert Service Bulletin MD90-24A031, Revision 01, dated February 28, 2001; as applicable. 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 Airplanes, 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; or 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. Effective Date (h) This amendment becomes effective on May 11, 2004. Issued in Renton, Washington, on March 22, 2004. Kalene C. Yanamura, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 04-7350 Filed 4-5-04; 8:45 am] BILLING CODE 4910-13-P