AD 2004-03-23 Airworthiness Directives; Boeing Model 737-200 and -300 Series Airplanes Equipped With a Main Deck Cargo Door Installed in Accordance With Supplemental Type Certificate (STC) SA2969SO

Models named: 737-200, -300 series. Read the applicability below — it usually turns on serial or part numbers too.

Model 737-200 and -300 series airplanes, equipped with a main deck cargo door installed in accordance with Supplemental Type Certificate (STC) SA2969SO; certificated in any category.

Required as indicated, unless accomplished previously. To detect and correct cracking of the lower portion of the main deck cargo door frames, which could result in sudden depressurization, loss or opening of the main deck cargo door during flight, and loss of control of the airplane; accomplish the following: Actions Addressing Door Frames or Reinforcing Angles That Have Been Replaced (a) For airplanes on which any door frame or reinforcing angle at the location where the door latch fittings attach between fuselage station (FS) 361.86 and FS 498.12 and water line (WL) 202.35 and WL 213.00 has been replaced before the effective date of this AD: Do the actions specified in paragraphs (a)(1) and (a)(2) of this AD per the Accomplishment Instructions of Pemco Service Bulletin 737-52-0037, Revision 2, dated September 13, 2000, including Attachment 1, dated August 10, 2000. (1) Within 3,000 flight cycles after accomplishment of the replacement, do a high frequency eddy current (HFEC) inspection to detect cracks of the replaced lower frames or replaced reinforcing angles of the main deck cargo door, as applicable. (i) If no crack is detected, repeat the HFEC inspection thereafter at intervals of 1,300 flight cycles on the replaced part. (ii) If any crack is detected, before further flight, replace the cracked part with a new part having the same part number per the service bulletin. Within 3,000 flight cycles after accomplishment of the replacement, do the HFEC inspection required by paragraph (a)(1) of this AD. (2) Before or upon the accumulation of 7,000 total flight cycles on any lower frame or reinforcing angle of the main deck cargo door, replace the lower frame or reinforcing angle, as applicable, with new parts. Within 3,000 flight cycles after accomplishment of the replacement, do the HFEC inspection required by paragraph (a)(1) of this AD. Actions Addressing Door Frames or Reinforcing Angles That Have Not Been Replaced (b) For airplanes on which any door frame or reinforcing angle at the location where the door latch fittings attach between FS 361.86 and FS 498.12 and WL 202.35 and WL 213.00 has not been replaced before the effective date of this AD: Within 1,300 flight cycles after accomplishment of the HFEC inspection required by AD 2000-17-51, amendment 39-11877, do the action specified in either paragraph (b)(1) or (b)(2) of this AD, as applicable, per the Accomplishment Instructions of Pemco Service Bulletin 737-52-0037, Revision 2, dated September 13, 2000, including Attachment 1, dated August 10, 2000. (1) For airplanes that have accumulated less than 7,000 total flight cycles since installation of STC SA2969SO: Do an HFEC inspection to detect cracks of the lower frames and reinforcing angles of the main deck cargo door where the door latch fittings attach between FS 361.86 and FS 498.12 and WL 202.35 and WL 213.00. (i) If no crack is detected, do the actions specified in paragraphs (b)(1)(i)(A) and (b)(1)(i)(B) of this AD. (A) Repeat the HFEC inspection thereafter at intervals of 1,300 flight cycles on the airplane, but not to exceed the accumulation of 7,000 total flight cycles on the airplane. (B) Before the accumulation of 7,000 total flight cycles on the airplane, replace the lower frame and reinforcing angle with new parts per the service bulletin. Within 3,000 flight cycles after accomplishment of the replacement, do the HFEC inspection required by paragraph (a)(1) of this AD. (ii) If any crack is detected, before further flight, replace the cracked part with a new part having the same part number per the service bulletin. Within 3,000 flight cycles after accomplishment of the replacement, do the HFEC inspection required by paragraph (a)(1) of this AD. (2) For airplanes that have accumulated 7,000 or more total flight cycles since installation of STC SA2969SO: Replace the lower frames and reinforcing angles with new parts. Within 3,000 flight cycles after accomplishment of the replacement, do the HFEC inspection required by paragraph (a)(1) of this AD. Alternative Methods of Compliance (c)(1) In accordance with 14 CFR 39.19, the Manager, Atlanta Aircraft Certification Office (ACO), FAA, is authorized to approve alternative methods of compliance (AMOCs) for this AD. (2) Alternative methods of compliance, approved previously in accordance with AD 2000-17-51, amendment 39-11877, are approved as alternative methods of compliance with the initial HFEC inspection required by paragraph (a)(1) of this AD. Incorporation by Reference (d) The actions shall be done in accordance with Pemco Service Bulletin 737-52-0037, Revision 2, dated September 13, 2000, including Attachment 1, dated August 10, 2000. This incorporation by reference was approved previously by the Director of the Federal Register as of May 29, 2001 (66 FR 20380, April 23, 2001). Copies may be obtained from Pemco World Air Services, 100 Pemco Drive, Dothan, AL 36303. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, Suite 450, Atlanta, Georgia; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. Effective Date (e) This amendment becomes effective on February 24, 2004. Issued in Renton, Washington, on January 30, 2004. Kalene C. Yanamura, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 04-2575 Filed 2-6-04; 8:45 am] BILLING CODE 4910-13-P