93-20-03 LOCKHEED: Amendment 39-8710. Docket 92-NM-241-AD.
Applicability: All Model L-1011 series airplanes, certificated in any category.
Compliance: Required as indicated, unless accomplished previously.
NOTE 1: This AD references Lockheed Document Number LR 31889, "Corrosion Prevention and Control Program, TriStar L-1011," dated March 15, 1991, including "Errata Sheet, LR 31889, Corrosion Prevention and Control Program, TriStar L-1011," issued September 29, 1992 (hereafter, both publications are referred to as "the Document"), for corrosion tasks, definitions of corrosion levels, compliance times, and reporting requirements. In addition, this AD specifies inspection and reporting requirements beyond those included in the Document. Where there are differences between the AD and the Document, the AD prevails.
NOTE 2: As used throughout this AD, the term "the FAA" is defined differently for different operators, as follows: For those operators complying with paragraph (a) of this AD, "the FAA" is defined as "the Manager of the Atlanta Aircraft Certification Office (ACO)." For those operators operating under Federal Aviation Regulation (FAR) Part 121 or 129, and complying with paragraph (b) of this AD, "the FAA" is defined as "the cognizant PMI." For those operators operating under FAR Part 91 or 125, and complying with paragraph (b) of this AD, "the FAA" is defined as "the cognizant Maintenance Inspector at the appropriate FAA Flight Standards office."
To preclude structural failure due to corrosion, accomplish the following:
(a) Except as provided in paragraph (b) of this AD, complete each of the corrosion tasks specified in Section 4 of the Document in accordance with the procedures of the Document, and the schedule specified in paragraphs (a)(1) and (a)(2) of this AD. Corrosion task numbers C-32-710-01 (nose landing gear) and C-32-730-01 (main landing gear, left and right) are not required to be accomplished as part ofthis AD.
NOTE 3: A "corrosion task," as defined in Section 4 of the Document, includes inspections; procedures for a corrective action, including repairs, under identified circumstances; application of corrosion inhibitors; and other follow-on actions.
NOTE 4: Corrosion tasks completed in accordance with the Document before the effective date of this AD may be credited for compliance with the initial corrosion task requirements of paragraph (a)(1) of this AD.
NOTE 5: Where non-destructive inspection (NDI) methods are employed, in accordance with Section 4 of the Document, the standards and procedures used must be acceptable to the Administrator in accordance with FAR Section 43.13.
(1) Complete the initial corrosion task of each "airplane area" specified in Section 4 of the Document as follows:
(i) For airplane areas that have not yet exceeded the "implementation age" (IA) for a corrosion task as of one year after the effective date of this AD: Initial compliance must occur no later than the IA plus the repeat (R) interval.
(ii) For airplane areas that have exceeded the IA for a particular corrosion task, as of one year after the effective date of this AD: Initial compliance must occur within one R interval for that task, measured from a date one year after the effective date of this AD.
(iii) For airplanes that are 20 years old or older as of one year after the effective date of this AD: Initial compliance must occur for each corrosion task within one R interval for that task, but not to exceed 6 years, measured from a date one year after the effective date of this AD, whichever occurs first.
(iv) Notwithstanding paragraph (a)(1)(i), (a)(1)(ii), and (a)(1)(iii) of this AD, for airplane areas that exceed the IA for that area, the operator must accomplish the initial corrosion task for each such area at a minimum rate equivalent to one such area per year, beginning one year after the effective date of this AD.NOTE 6: This paragraph does not require inspection of any area that has not exceeded the IA for that area.
NOTE 7: This minimum rate requirement may cause an undue hardship on some small operators. In those circumstances, requests for adjustments to the implementation rate will be evaluated on a case-by-case basis under the provisions of paragraph (h) of this AD.
(2) Repeat each corrosion task at a time interval not to exceed the R interval specified in the Document for that task.
(b) As an alternative to the requirements of paragraph (a) of this AD: Prior to one year after the effective date of this AD, revise the FAA-approved maintenance/inspection program to include the corrosion prevention and control program specified in the Document; or to include an equivalent program that is approved by the FAA. In all cases, the initial corrosion task for each airplane area must be completed in accordance with the compliance schedule specified in paragraph (a)(1) of this AD. Corrosion task numbers C-32-710-01 (nose landing gear) and C-32-730-01 (main landing gear, left and right) are not required to be accomplished as part of this AD.
(1) Any operator complying with paragraph (b) of this AD may use an alternative recordkeeping method to that otherwise required by FAR Section 91.417 or Section 121.380 for the actions required by this AD, provided it is approved by the FAA and is included in a revision to the FAA-approved maintenance/inspection program.
(2) Subsequent to the accomplishment of the initial corrosion task, extensions of R intervals specified in the Document must be approved by the FAA.
(c) To accommodate unanticipated scheduling requirements, it is acceptable for an R interval to be increased by up to 10%, but not to exceed 6 months. The FAA must be informed, in writing, of any such extension within 30 days after such adjustment of the schedule.
(d) (1) If, as a result of any inspection conducted in accordance with paragraphs (a) or (b) of this AD, Level 3 corrosion is determined to exist in any airplane area, accomplish either paragraph (d)(1)(i) or (d)(1)(ii) within 7 days after such determination:
(i) Submit a report of that determination to the FAA and complete the corrosion task in the affected areas on all Model L-1011 series airplanes in the operator's fleet; or
(ii) Submit to the FAA for approval one of the following:
(A) A proposed schedule for performing the corrosion tasks in the affected areas on the remaining Model L-1011 series airplanes in the operator's fleet, which is adequate to ensure that any other Level 3 corrosion is detected in a timely manner, along with substantiating data for that schedule; or
(B) Data substantiating that the Level 3 corrosion found is an isolated occurrence.
NOTE 8: Notwithstanding the provisions of Section 1 of the Document, which would permit corrosion that otherwise meets the definition of Level 3 corrosion (i.e., which is determined to be a potentially urgent airworthiness concern requiring expeditious action) to be treated as Level 1 if the operator finds that it "can be attributed to an event not typical of the operator's usage of other airplanes in the same fleet," this paragraph requires that data substantiating any such finding be submitted to the FAA for approval.
(2) The FAA may impose schedules other than those proposed, upon finding that such changes are necessary to ensure that any other Level 3 corrosion is detected in a timely manner.
(3) Within the time schedule approved under paragraph (d)(1) or (d)(2) of this AD, accomplish the corrosion tasks in the affected areas of the remaining Model L-1011 series airplanes in the operator's fleet.
(e) If, as a result of any inspection after the initial inspection conducted in accordance with paragraphs (a) or (b) of this AD, it is determined that corrosion findings exceed Level 1 in any area, within 60 days after such determination, implement a means, approved by the FAA, to reduce future findings of corrosion in that area to Level 1 or better.
(f) Before any operator places into service any airplane subject to the requirements of this AD, a schedule for the accomplishment of corrosion tasks required by this AD must be established in accordance with paragraph (f)(1) or (f)(2) of this AD, as applicable:
(1) For airplanes previously maintained in accordance with this AD, the first corrosion task in each airplane area to be performed by the new operator must be accomplished in accordance with the previous operator's schedule or with the new operator's schedule, whichever would result in the earlier accomplishment date for that task. After each corrosion task has been performed once, each subsequent task must be performed in accordance with the new operator's schedule.
(2) For airplanes that have not been previously maintained in accordance with this AD, the first corrosion task for each airplane area to be performed by the new operator must be accomplished prior to further flight or in accordance with a schedule approved by the FAA.
(g) Reports of Level 2 and Level 3 corrosion must be submitted at least quarterly to Lockheed Aeronautical Systems in accordance with Section 5 of the Document.
NOTE 9: Reporting of Level 2 and Level 3 corrosion found as a result of any opportunity inspections is highly desirable.
(h) 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, Atlanta Aircraft Certification Office (ACO), FAA, Small Airplane Directorate. Operators shall submit their requests through the cognizant Maintenance Inspector at the appropriate FAA Flight Standards office, who may concur or comment and then send it to the Manager, Atlanta ACO.
NOTE 10: Information concerning the existence of approved alternative methods of compliance with thisAD, if any, may be obtained from the Atlanta ACO.
(i) Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with the requirements of this AD.
(j) Reports of corrosion inspection results required by this AD have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.
(k) The completion of the corrosion tasks shall be done in accordance with Lockheed Document Number LR 31889, "Corrosion Prevention and Control Program, TriStar L-1011," dated March 15, 1991; including "Errata Sheet, LR 31889, Corrosion Prevention and Control Program, TriStar L-1011," issued September 29, 1992. 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 Lockheed Western Export Company, Attn: Commercial and Customer Support, Dept. 693, Zone 0755, 86 South Cobb Drive, Marietta, Georgia 30063. Copies may be inspected at the Federal Aviation Administration (FAA), Transport Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Atlanta Aircraft Certification Office, 1669 Phoenix Parkway, Suite 210C, Atlanta, Georgia; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
(l) This amendment becomes effective on December 17, 1993.