AIRWORTHINESS DIRECTIVE

CAA-AD-039/2001

Supersedes CAA-AD-081/2000

Date of issue: May 09, 2001

AIRCRAFT - MAIN DECK CARGO DOOR - INSPECTION/REPLACEMENT

Applicability: 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.

Effective date: June 14, 2001

Compliance: Required as indicated in FAA AD 2000-08-07.

Remarks: The compliance of this AD must be recorded in Aircraft Logbook, where applicable the requirements of this AD must be integrated into Aircraft Technical Documentation. Address inquiries concerning this AD to: Civil Aviation Authority, Airworthiness Division, Ruzyne Airport, 160 08 Prague 6, Czech Republic, tel: 420 2 33320922, fax: 420 2 20562270.

Ing. Pavel MATOUŠEK

Director of Airworthiness Division

CAA CZ

2001-08-07 BOEING: Amendment 39-12184. Docket 2000-NM-295-AD. Supersedes AD 2000-17-51, Amendment 39-11877.

Applicability:

Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been otherwise 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 (c)(1) 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 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 298.12 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 298.12 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 361.87 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.

(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) 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, Atlanta 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, Atlanta ACO.

Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Atlanta ACO.

(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.

Special Flight Permits

(d) 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.

Incorporation by Reference

(e) 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, which contains the list of effective pages specified in Table 1 of this AD. Table 1 is as follows:

Table 1.

Page Number	Revision Level Shown on Page	Date Shown on Page
1	A	August 15, 2000
2, 3, 6-10	Original	August 10, 2000
4, 4a, 5	2	September 13, 2000
Attachment 1, 2	Original	August 10, 2000

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 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

(f) This amendment becomes effective on May 29, 2001.

FOR FURTHER INFORMATION CONTACT: William Culler, Aerospace Engineer, Airframe and Propulsion Branch, ACE-117A, FAA, Atlanta Aircraft Certification Office, One Crown Center, 1895 Phoenix Boulevard, Suite 450, Atlanta, Georgia 30337-2748, telephone (770) 703-6084; fax (770) 703-6097.

Issued in Renton, Washington, on April 12, 2001.

Donald L. Riggin, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.