AIRWORTHINESS DIRECTIVE

CAA-AD-039/2000R1

Revises CAA-AD-039/2000

Date of issue: August 06, 2001

AIRCRAFT - AFT CARGO DOOR - INSPECTION

Applicability: The following airplane models, certificated in any category:

Model 737-200 and -200C series airplanes, line numbers 6 through 873 inclusive;

Model 737-200, -200C, -300, and -400 series airplanes; line numbers 874 through 1642 inclusive; equipped with an aft cargo door having Boeing part number (P/N) 65-47952-1 or P/N 65-47952-524; excluding:

1. Those airplanes on which that door has been modified in accordance with Boeing Service Bulletin 737-52-1079; or

2. Those airplanes on which the door assembly having P/N 65-47952-524 includes four straps (P/N’s 65-47952-139, 65-47952-140, 65-47952-141, and 65-47952-142) and a thicker lower cross beam web (P/N 65-47952-157).

Effective date: October 04, 2001

Compliance: Required as indicated in FAA AD 2000-06-13 R1.

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

REVISION

2000-06-13 R1 Boeing: Amendment 39-12317. Docket 2000-NM-205-AD. Revises AD 2000-06-13, Amendment 39-11654.

Applicability: The following airplane models, certificated in any category.

Model 737-200 and -200C series airplanes, line numbers 6 through 873 inclusive; Model 737-200, -200C, -300, and -400 series airplanes; line numbers 874 through 1642 inclusive; equipped with an aft cargo door having Boeing part number (P/N) 65-47952-1 or P/N 65-47952-524; excluding:

1. Those airplanes on which that door has been modified in accordance with Boeing Service Bulletin 737-52-1079; or

2. Those airplanes on which the door assembly having P/N 65-47952-524 includes four straps (P/N's 65-47952-139, 65-47952-140, 65-47952-141, and 65-47952-142) and a thicker lower cross beam web (P/N 65-47952-157).

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 (f)(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 prevent fatigue cracking of the corners of the doorframe and the cross beams of the aft cargo door, which could result in rapid depressurization of the airplane, accomplish the following:

Restatement of the Requirements of AD 2000-06-13

Inspections and Corrective Actions

(a) Within 90 days or 700 flight cycles after December 24, 1998 (the effective date of AD 98-25-06, amendment 39-10931), whichever occurs later, perform an internal detailed visual inspection to detect cracking of the corners of the door frame and the cross beams of the aft cargo door, in accordance with Boeing Service Bulletin 737-52-1079, Revision 5, dated May 16, 1996; or Boeing Alert Service Bulletin 737-52A1079, Revision 6, dated November 18, 1999.

(1) If no cracking is detected, accomplish the requirements of either paragraph (a)(1)(i) or (a)(1)(ii) of this AD.

(i) Repeat the internal visual inspection thereafter at intervals not to exceed 4,500 flight cycles. Or

(ii) Prior to further flight, modify the corners of the doorframe and the crossbeams of the aft cargo door in accordance with the service bulletin. Accomplishment of such modification constitutes terminating action for the repetitive inspection requirements of paragraph (a)(1)(i) of this AD.

(2) If any cracking is detected in the upper or lower cross beams, prior to further flight, modify the cracked beam in accordance with Part I of the Accomplishment Instructions of the service bulletin. Accomplishment of such modification constitutes terminating action for the repetitive inspection requirements of paragraph (a)(1)(i) of this AD for the repaired beam.

(3) If any cracking is detected in the forward or aft upper door frame, prior to further flight, repair the frame and modify the corners of the door frame of the aft cargo door, in accordance with Part I of the Accomplishment Instructions of the service bulletin, except as provided by paragraph (b) of this AD. Accomplishment of such modification constitutes terminating action for the repetitive inspection requirements of paragraph (a)(1)(i) of this AD for the upper doorframe.

Note 2: Cracks of the forward or aft upper door frame, regardless of length, must be repaired prior to further flight in accordance with Part I of the Accomplishment Instructions of the service bulletin.

(4) If any cracking is detected in the forward or aft lower door frame, prior to further flight, replace the damaged frame with a new frame, and modify the corners of the door frame of the aft cargo door, in accordance with Part I of the Accomplishment Instructions of the service bulletin. Accomplishment of such modification constitutes terminating action for the repetitive inspection requirements of paragraph (a)(1)(i) of this AD for the lower doorframe.

(b) Where Boeing Service Bulletin 737-52-1079, Revision 5, dated May 16, 1996; or Boeing Alert Service Bulletin, 737-52A1079, Revision 6, dated November 18, 1999; specifies that certain repairs are to be accomplished in accordance with instructions received from Boeing, this AD requires that, prior to further flight, such repairs be accomplished in accordance with a method approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA.

Inspections and Corrective Actions

(c) If any cracking of the outer chord of the upper or lower cross beams of the aft cargo door is detected as a result of any inspection required by paragraph (a) of this AD, prior to further flight, repair in accordance with a method approved by the Manager, Seattle ACO; Boeing Alert Service Bulletin 737-52A1079, Revision 6, dated November 18, 1999; or in accordance with data meeting the type certification basis of the airplane approved by a Boeing Company Designated Engineering Representative who has been authorized by the FAA to make such findings. For a repair method to be approved by the Manager, Seattle ACO, as required by this paragraph, the Manager's approval letter must specifically reference this AD.

(d) Within 4,500 flight cycles or 1 year after May 9, 2000 (the effective date of AD 2000-06-13, amendment 39-11654), whichever occurs later: Perform a high frequency eddy current inspection (HFEC) to detect cracking of the four corners of the door frame of the aft cargo door, in accordance with the procedures specified in Boeing 737 Nondestructive Test Manual, Part 6, Chapter 51-00-00 (Figure 4 or Figure 23); or Boeing Alert Service Bulletin 737-52A1079, Revision 6, dated November 18, 1999.

(1) If no cracking of the corners of the doorframe of the aft cargo door is detected, repeat the HFEC inspections thereafter at intervals not to exceed 4,500 flight cycles until accomplishment of the modification specified in paragraph (e) of this AD.

(2) If any cracking of the corners of the door frame of the aft cargo door is detected, prior to further flight, replace the damaged frame with a new frame, and modify the four corners of the door frame, in accordance with Parts II and III of the Accomplishment Instructions of Boeing Service

Bulletin 737-52-1079, Revision 5, dated May 16, 1996; or Boeing Alert Service Bulletin 737-52A1079, Revision 6, dated November 18, 1999. Accomplishment of such modification constitutes terminating action for the repetitive inspection requirements of paragraph (d)(1) of this AD for that doorframe.

Requirement Revised by This AD

Terminating Action

(e) Within 4 years or 12,000 flight cycles after the effective date of this AD, whichever occurs later: Modify the four corners of the door frame and the cross beams of the aft cargo door, in accordance with Part II of the Accomplishment Instructions of Boeing Service Bulletin 737-52-1079, Revision 5, dated May 16, 1996; or Boeing Alert Service Bulletin 737-52A1079, Revision 6, dated November 18, 1999. Accomplishment of that modification constitutes terminating action for the repetitive inspection requirements of this AD.

Note 3: Accomplishment of the modification required by paragraph (a) of AD 90-06-02, amendment 39-6489, is considered acceptable for compliance with paragraph (e) of this AD.

Note 4: Modification of the corners of the door frame and the cross beams of the aft cargo door accomplished prior to the effective date of this AD in accordance with Boeing Service Bulletin 737-52-1079, dated December 16, 1983; Revision 1, dated December 15, 1988; Revision 2, dated July 20, 1989; Revision 3, dated May 17, 1990; or Revision 4, dated February 21, 1991; is considered acceptable for compliance with paragraph (e) of this AD.

Alternative Methods of Compliance

(f) (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, Seattle ACO. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO.

(2) Alternative methods of compliance, approved previously in accordance with AD 98-25-06, amendment 39-10931, are approved as alternative methods of compliance with this AD.

Note 5: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO.

Special Flight Permits

(g) Special flight permits may be issued in accordance with Secs. 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

(h) Except as provided in paragraphs (b), (c), and (d) of this AD, the actions shall be done in accordance with Boeing Service Bulletin 737-52-1079, Revision 5, dated May 16, 1996; or Boeing Alert Service Bulletin 737-52A1079, Revision 6, dated November 18, 1999.

(1) The incorporation by reference of Boeing Alert Service Bulletin 737-52A1079, Revision 6, dated November 18, 1999, was approved previously by the Director of the Federal Register as of May 9, 2000 (65 FR 17583, April 4, 2000).

(2) The incorporation by reference of Boeing Service Bulletin 737-52-1079, Revision 5, dated May 16, 1996, was approved previously by the Director of the Federal Register as of December 24, 1998 (63 FR 67769, December 9, 1998).

(3) Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Effective Date

(i) This amendment becomes effective on August 15, 2001.

Issued in Renton, Washington, on July 2, 2001.

Vi L. Lipski, Manager, Transport Airplane Directorate, Aircraft Certification Service.

BILLING CODE [4910-13-P]