AD 92-10-03

92-10-03 BRITISH AEROSPACE: Amendment 39-8236. Docket No. 91-NM-97-AD. Applicability: British Aerospace Model BAe 146 series airplanes, as listed in British Aerospace Inspection Service Bulletins 24-83 and 24-84, both dated January 22, 1991; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent a fire and to provide overheat protection, accomplish the following:

(a) Within 60 days after the effective date of this AD, and thereafter at intervals not to exceed 180 days for a period of two years after the initial inspections, perform a visual inspection of the in-line splices in the Auxiliary Power Unit (APU) generator circuits for heat damage, in accordance with the Accomplishment Instructions in British Aerospace Inspection Service Bulletin 24-83, dated January 22, 1991.

NOTE: The FAA has determined that if the in-line splices do not show signs of overheating within a two-year period of time, no problemwill develop.

(1) If heat-damaged splices are found, prior to further flight, accomplish one of the following:

(i) Perform a temporary repair in accordance with paragraph 2.A(4) of British Aerospace Inspection Service Bulletin 24-83, dated January 22, 1991, by installing Modification HCM50134A, as described in Modification Service Bulletin 24-83-50134A, Revision 1, dated March 15, 1991; or

(ii) Perform a permanent repair in accordance with paragraph 2.A(4) of British Aerospace Inspection Service Bulletin 24-83, dated January 22, 1991, by installing Modification HCM36097A or Modification HCM36097B, as described in Modification Service Bulletin 24-82-36097A&B, dated February 11, 1991.

(2) Accomplishment of one of the modifications at a splice location in accordance with either paragraphs (a)(1)(i) or (a)(1)(ii) of this AD, constitutes terminating action for the requirements for the repetitive inspections required by paragraph (a) of this AD at that splice location.

(b) Within 60 days after the effective date of this AD, and thereafter at intervals not to exceed 180 days for a period of two years after the initial inspection, perform a visual inspection of all in-line splices in the integrated drive generator circuits, in accordance with the Accomplishment Instructions in British Aerospace Inspection Service Bulletin 24-84, dated January 22, 1991.

(1) If heat-damaged splices are found, prior to further flight, accomplish one of the following:

(i) Perform a temporary repair in accordance with paragraph 2.A(4) of British Aerospace Inspection Service Bulletin 24-84, dated January 22, 1991, by installing Modification HCM50134B, as described in Modification Service Bulletin 24-84-50134B, Revision 1, dated March 15, 1991; or

(ii) Perform a permanent repair in accordance with paragraph 2.A(4) of British Aerospace Inspection Service Bulletin 24-84, dated January 22, 1991, by installing Modification HCM01253A, as described in Modification Service Bulletin 24-85-01253A, Revision 1, dated March 15, 1991.

(2) Accomplishment of one of the modifications at a splice location in accordance with paragraphs (b)(1)(i) or (b)(1)(ii) of this AD, constitutes terminating action for the requirements for the repetitive inspections required by paragraph (b) of this AD at that splice location.

(c) Temporary repairs made at a splice location in accordance with paragraphs (a) or (b) of this AD, and temporary repairs made previously in accordance with British Aerospace Service Bulletin 24-A75 or 24-A76, must be replaced with a permanent repair at that splice location within 12 months after the temporary repair was installed, or within 12 months after the effective date of this AD, whichever occurs later, in accordance with British Aerospace Service Bulletin 24-83, dated January 22, 1991, or British Aerospace Service Bulletin 24-84, dated January 22, 1991, as applicable.

(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, Standardization Branch, ANM-113, 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, Standardization Branch, ANM-113.

(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 modifications, inspections, and repairs shall be done in accordance with the following British Aerospace Service Bulletins, which contain the specified list of effective pages:

Service Bulletin No. Page Revision Level Date

Inspection Service 1-4 Original January 22, 1991 Bulletin 24-83

Modification Service 1-13 Original February 11, 1991 Bulletin 24-82-36097A&B

Inspection Service 1-5 Original January 22, 1991 Bulletin 24-84

Modification Service 1, 2, 9 Revision 1 March 15, 1991 Bulletin 24-83-50134A 3-4, 5, Original Undated

6, 7-8

Modification Service 1, 2, 11 Revision 1 March 15, 1991 Bulletin 24-84-50134B 3-4, 5, Original Undated

6, 7-8,

9-10

Modification Service 1, 3-4, Revision 1 March 15, 1991 Bulletin 24-85-01253A 11

2, 5, 6, Original Undated

7-8, 9-10

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 British Aerospace, PLC, Librarian for Service Bulletins, P.O. Box 17414, Dulles International Airport, Washington, D.C. 20041. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or at the Office of the Federal Register, 1100 L Street NW., Room 8401, Washington, DC.

(g) This amendment becomes effective on June 12, 1992.