AD 97-10-08

97-10-08 CONSTRUCCIONES AERONAUTICAS, S.A., CASA: Amendment 39-10020. Docket 96-NM-138-AD. Applicability: Model CN-235 series airplanes, as listed in CASA Service Bulletin SB-235-52-23, Revision 2, dated June 9, 1994, and CASA Service Bulletin SB-235-52-23M, dated March 17, 1994; certificated in any category.

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 (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 fatigue-related cracking in the guide hooks of the cargo door, which could result in reduced structural integrity of the cargo door and, consequently, lead to rapid decompression of the airplane, accomplish the following:

(a) Replace the guide hooks of the cargo doors with new, improved guide hooks, in accordance with CASA Service Bulletin SB-235-52-23, Revision 2, dated June 9, 1994, or CASA Service Bulletin SB-235-52-23M, dated March 17, 1994; at the time specified in paragraph (a)(1) or (a)(2) of this AD, as applicable.

NOTE 2: Replacements accomplished prior to the effective date of this AD in accordance with CASA Service Bulletin SB-235-52-23, dated June 16, 1993, or Revision 1, dated April 13, 1994, are considered acceptable for compliance with the requirements of paragraph (a) of this AD.

(1) For airplaneslisted in CASA Service Bulletin SB-235-52-23: Replace prior to the accumulation of 17,000 total landings.

(2) For airplanes listed in CASA Service Bulletin SB-235-52-23M: Replace prior to the accumulation of 15,000 total landings.

(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, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Standardization Branch, ANM-113.

NOTE 3: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

(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 replacement shall be done in accordance with CASA Service Bulletin SB-235-52-23, Revision 2, dated June 9, 1994, or CASA Service Bulletin SB-235-52-23M, dated March 17, 1994. CASA Service Bulletin SB-235-52-23, Revision 2, dated June 1994, contains the following list of effective pages:

Page Number Revision Level Shown on Page Date Shown on Page 1 1 April 13, 1994 2 2 June 9, 1994 3-9 Original June 16, 1993

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 Construcciones Aeronauticas, S.A., Getafe, Madrid, Spain. 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.

(e) This amendmentbecomes effective on June 16, 1997.