81-18-51 R4 LOCKHEED-CALIFORNIA COMPANY: Amendment 39-4242 as amended by Amendment 39-4279 and 39-4365 is further amended by Amendment 39-4723. Applies to Lockheed Model L-1011-385-1 airplanes, Serial Numbers 1001 through 1051, inclusive, certificated in all categories.
Compliance is required in accordance with paragraphs A and B or C below, unless previously accomplished:
A. Compliance Schedule
1. Compliance is required within 50 hours time in service after the effective date of this AD, and at intervals not to exceed 300 hours time in service thereafter. Previously accomplished inspections, if conducted subsequent to August 15, 1981, and in accordance with paragraph B or C below, may be used to satisfy the initial 50 hours inspection requirement of this AD.
2. If operators elect to accomplish the inspections in accordance with paragraph C below, the repetitive inspection interval not to be exceeded is 1000 landings on airplanes with no structural damage and on repaired airplanes that have no repairs or structural damage to the bulkhead cap. Any aircraft with repairs to the bulkhead cap must be inspected at intervals not to exceed 500 landings. If the bulkhead cap repair had been accomplished prior to the effective date of this amendment, the next X-ray inspection to the bulkhead cap must be accomplished within 1000 landings from the date of the repair or 500 landings from the effective date of this amendment, whichever is earlier. Thereafter, inspect per X-ray inspection procedures at intervals not to exceed 500 landings.
3. Permanent modifications to the FS 1363 bulkhead structure in accordance with Lockheed-California Company L-1011 Service Bulletin 093-53-207, dated January 26, 1982, or later revisions approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region, eliminates the requirement for the periodic inspections specified in this AD.
To detect cracks in the Fuselage Station (FS) 1363 bulkhead lower cap, fuselage skin, adjacent web, and web horizontal stiffeners and prevent failure and possible sudden decompression of the pressurized fuselage, accomplish the following:
B. Accomplishment Instructions: OPTION 1
1. Remove main landing gear fairing panel 195B, left hand side.
2. Remove main landing gear fairing panel 196B, right hand side.
3. Perform a close visual inspection for cracks in Fuselage Station 1363 bulkhead, left hand side. Inspect from the main landing gear wheel well paying particular attention to web and horizontal stiffeners at bulkhead cap, above and below water line 140.
4. Perform a close visual inspection for cracks in fuselage skin between Fuselage Stations 1363 and 1403, left hand side, paying particular attention to the area between Stringers 44 and 45.
5. Perform a close visual inspection for cracks in Fuselage Station 1363 bulkhead, right hand side. Inspect from the main landing gear wheel well paying particular attention to the web and horizontal stiffeners at the bulkhead cap, above and below water line 140.
6. Perform a close visual inspection for cracks in the fuselage skin between Fuselage Stations 1363 and 1403, right hand side, paying particular attention to the area between Stringers 21 and 22.
C. Accomplishment Instructions OPTION 2
1. Inspect for cracks in FS 1363 bulkhead cap and surrounding areas in accordance with Lockheed L-1011 Service Bulletin 093-53-206, Revision 2, dated April 22, 1983, or later revisions approved by the Manager, Los Angeles Aircraft Certification Office, FAA, Northwest Mountain Region.
D. All cracks found must be repaired before further flight in a manner approved by the Manager, Los Angeles Aircraft Certification Office, FAA Northwest Mountain Region.
E. Alternative means of compliance with this AD which provide an equivalent level of safety may be used when approved by the Manager, Los Angeles Aircraft CertificationOffice, FAA Northwest Mountain Region.
The manufacturer's specifications and procedures identified and described in this directive are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1).
All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Lockheed-California Company, P.O. Box 551, Burbank, California 91520, Attention: Commercial Support Contracts, Dept. 63-11, U-33, B-1. These documents also may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or the Los Angeles Aircraft Certification Office, 4344 Donald Douglas Drive, Long Beach, California 90808.
Amendment 39-4242 became effective November 5, 1981, to all persons, except those to whom it was made immediately effective by Telegraphic AD T81-18-51, dated August 21, 1981.
Amendment 39-4279 became effective December 24, 1981.
Amendment 39-4365 becameeffective April 26, 1982.
This Amendment 39-4723 becomes effective September 21, 1983.