91-08-11 BRITISH AEROSPACE: Amendment 39-6966; Docket No. 90-NM-237-AD.
Applicability: Model BAe 146-200A series airplanes; Serial Numbers E2022 through E2025, E2028, E2030, E2031, E2034, E2036, and E2039 through E2048; certificated in any category.
Compliance: Required as indicated, unless previously accomplished.
To prevent reduced structural integrity of the fuselage pressure vessel, accomplish the following:
A. For airplanes Serial Numbers E2022 through E2025, E2028, E2030, E2031, E2034, E2036, E2039 through E2048: Accomplish the following:
1. Within 30 days after the effective date of this AD, perform the following inspections:
a. A detailed visual inspection (including the use of a dial test indicator and 10X magnifying glass, where appropriate) of the rivets in the polished fuselage skins and the polished fuselage skins to detect rivet abrasion damage, loose or missing rivets, and skin cracks, in accordance with paragraphs 2.A. and 2.B. of the Accomplishment Instructions of British Aerospace Service Bulletin 53-87, dated January 19, 1990.
b. An ultrasonic inspection of the fuselage skin, to detect reduced skin thickness, in accordance with paragraphs 2.A. and 2.B. of the Accomplishment Instructions of British Aerospace Service Bulletin 53-87, dated January 19, 1990.
2. Repeat the inspections required by paragraph A.1. of this AD at intervals not to exceed 1,500 flights, as follows:
a. For fuselage sections of the airplane that continue to be polished, perform visual and ultrasonic inspections on alternate halves of the fuselage (e.g., left and then right, etc.), in accordance with paragraphs 2.A. and 2.B. of the Accomplishment Instructions of British Aerospace Service Bulletin 53-87, dated January 19, 1990.
b. For fuselage sections that have had the fuselage skin painted subsequent to findings of rivet or skin damage resulting from polishing, perform only a visual inspection of those areas for skin cracks and loose or missing rivets.
c. For fuselage sections that have had the fuselage skin painted subsequent to findings of no rivet or skin damage resulting from polishing, no further action is required.
3. As a result of the inspections required by paragraph A.1. of this AD, accomplish the following:
a. If skin cracks or loose or failed rivets are found, prior to further flight, repair in a manner approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate.
b. Any rivets identified as category "A1" (between 0.002 to 0.000 inch in head height), must be replaced prior to further flight, with new rivets having the same part number, in accordance with paragraphs 2.A. and 2.B. of the Accomplishment Instructions of British Aerospace Service Bulletin 53-87, dated January 19, 1990.
c. At intervals not to exceed 1,500 flights, apply protective treatment to all rivets identified as having curvededges, in accordance with paragraph 2.A.9. of British Aerospace Service Bulletin 53-87, dated January 19, 1990.
B. For airplanes Serial Numbers E2022 through E2025, E2028, E2030, E2031, E2034, E2036, E2039 through E2048: Accomplish the following, in accordance with Paragraph 2.A. of British Aerospace Service Bulletin 53-98, dated September 26, 1990:
1. Within 6 months after the effective date of this AD, perform the following inspections:
a. A detailed visual inspection of the designated areas of the fuselage skins for signs of corrosion.
b. For airplanes that have been repainted, inspect the paint finish in the designated areas for underlying corrosion.
2. Repeat the inspections required by paragraph B.1. of this AD at intervals not to exceed 2,000 landings.
3. As a result of the inspections required by paragraph B.1. of this AD, accomplish the following:
a. If the paint finish in any area shows bubbling or other signs of distress, prior to further flight, the paint must be removed in accordance with Chapter 20-10-10 of the Airplane Maintenance Manual to allow a more detailed visual inspection to determine the extent of the damage.
b. If corrosion is found, prior to further flight, repair in a manner approved by the Manager, Standardization Branch, ANM-113, Transport Airplane Directorate.
C. For airplanes Serial Numbers E2022, E2024, E2025, E2028, E2036, and E2045: Accomplish the following, in accordance with British Aerospace Service Bulletin 53-88, dated January 19, 1990:
1. Prior to the accumulation of the number of flights identified in the "Compliance Period from Initial Polishing" column in paragraph D.1. of the service bulletin, perform a close visual inspection of the designated areas of the polished fuselage skin.
2. Repeat the inspections required by paragraph C.1. of this AD at intervals not to exceed 1,500 flights.
3. As a result of the inspections required by paragraph C.1. of this AD, accomplish the following:
a. If skin cracks or defects (loose or missing rivets) are found, prior to further flight, accomplish the following:
(1) Record the findings of cracks or defects, in accordance with paragraph 2.A.(3) of the service bulletin.
(2) If any loose rivets are found, remove the loose rivets and perform a detailed visual inspection to detect cracks around all vacant rivet holes using a 10X magnifying glass, in accordance with paragraph 2.A.(5) of the service bulletin.
(3) Repair cracks in a manner approved by the Manager, Standardization Branch, ANM-113, FAA Transport Airplane Directorate.
(4) Replace any missing or removed rivets with new rivets having the same part number.
b. If no cracks or defects are found, no further action is necessary for this inspection cycle.
D. Within 14 days after the inspections required by this AD, submit a report of all findings of the inspections, positive or negative, including charts, to British Aerospace, in accordance with Paragraph 2.A.(13) of British Aerospace Service Bulletin 53-87, dated January 19, 1990; Paragraph 2.A.(7) of Service Bulletin 53-88, dated January 19, 1990; and Paragraph 2.A.(4) of Service Bulletin 53-98, dated September 26, 1990.
E. 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, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate.
NOTE: The request should be forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Standardization Branch, ANM-113.
F. 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.
All persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. 20041-0414. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington.
This amendment (39-6966, AD 91-08-11) becomes effective on May 17, 1991.