AD 92-25-13

92-25-13 GENERAL DYNAMICS, CONVAIR DIVISION: Amendment 39-8427. Docket No. 92-NM-114-AD. Applicability: Model 240 [including originally Model T-29 (military) airplanes], 340, 440, and C-131 (military) airplanes; including those modified for turbo-propeller power (commonly referred to as Model 580, 600, and 640 series airplanes); all serial numbers; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent degradation of the structural capabilities of the airplane due to problems associated with corrosion, accomplish the following:

(a) Except as provided by paragraph (b) of this AD, conduct the initial inspection for each area/component within a period of time, measured from a date one year after the effective date of this AD, not to exceed the applicable interval specified in the "Initial" column of the schedule on pages 5-10-1 through 5-10-6 of Chapter 5 of General Dynamics, Convair Division, Document Number ZS-340-2000, "Supplemental Corrosion Inspection Document," dated February 1992 (hereafter referred to as "the Document"). Thereafter, repeat the inspections at intervals not to exceed the applicable interval specified in the "Follow-on" column of the schedule on pages 5-10-1 through 5-10-6 of the Document.

(b) As an alternative to the requirements of paragraph (a) of this AD:

(1) Within one year after the effective date of this AD, revise the FAA-approved maintenance inspection program to include the inspections of the areas and components defined in the Document; or incorporate an equivalent program that is approved by the FAA.

(2) After accomplishing the requirements of paragraph (b)(1) of this AD, conduct the initial inspection for each area/component at an interval not to exceed the applicable interval specified in the "Initial" column of the schedule on pages 5-10-1 through 5-10-6 of Chapter 5 of the Document. Thereafter, repeat the inspections at intervals not to exceedthe applicable interval specified in the "Follow-on" column of the schedule on pages 5-10-1 through 5-10-6 of Chapter 5 of the Document.

(c) If corrosion is detected as a result of any inspection required by this AD, prior to further flight, repair in accordance with the General Dynamics/Convair Structural Repair Manual (SRM) for the pertinent airplane model; or, if an applicable repair method is not contained in the SRM, in accordance with a method approved by the Manager, Los Angeles Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate.

(d) An alternative method of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Los Angeles ACO, FAA, Transport Airplane Directorate. The request shall be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Los Angeles ACO.

NOTE: Information concerning the existence ofapproved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Los Angeles ACO.

(e) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the airplane to a location where the requirements of this AD can be accomplished.

(f) The inspections shall be done in accordance with General Dynamics, Convair Division, Document Number ZS-340-2000, "Supplemental Corrosion Inspection Document," dated February 1992. (NOTE: Except for the title page of the document, no other pages of the document are dated.) 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 General Dynamics/Convair Division, Lindbergh Field Plant, P.O. Box 85377, San Diego, California 92138. Copies may be inspected at the FAA, Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at theLos Angeles Aircraft Certification Office, FAA, Transport Airplane Directorate, 3229 East Spring Street, Long Beach, California; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(g) This amendment becomes effective on January 12, 1993.