83-24-10 R1 BRITISH AEROSPACE: Amendment 39-4780 as amended by Amendment 39- 5053. Applies to Model BAC 1-11 200 and 400 series airplanes, certificated in all categories. Compliance is required as indicated unless already accomplished. To detect cracking and corrosion and to prevent structural failure of the fuselage pressure vessel with the resultant cabin depressurization, accomplish the following:
A. Within the next 12 months after the effective date of this AD, unless accomplished within the last 2 years, and thereafter at intervals not to exceed 3 years from the last inspection, visually inspect for corrosion and cracks the interior of the lower fuselage skin between stations 416-456 and stringers 32(LH) and 32(RH) and the interior of the lower fuselage skin between stations 630-690 and stringers 32(LH) and 32(RH), and ensure that drain paths in these areas are unobstructed, in accordance with paragraphs 2.1.1 and 2.1.2 of British Aerospace Alert Service Bulletin 53-A-PM5632, dated August 18, 1978.
B. On airplanes having long range fuel tanks or water injection tanks installed, accomplish the instructions of paragraph 2.1.3 of the service bulletin.
C. If cracks or corrosion are found during any inspection required by this AD, before further flight, rework or repair in accordance with Structural Repair Manual, Chapters 53-01-0 or 53-02-0 as appropriate, and continue the repetitive inspections at the intervals specified in paragraph A. of this AD.
D. Alternate means of compliance which provide an equivalent level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region.
E. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base for the accomplishment of inspections and/or modifications required by this AD.
Amendment 39-4780 became effective January 15, 1984.
This Amendment 39-5053 becomes effective June 4, 1985.