AD 93-13-03 ACTIVE

93-13-03 BRITISH AEROSPACE (COMMERCIAL AIRCRAFT), LIMITED: Amendment 39-8616. Docket 93-NM-89-AD.
Applicability: Model ATP series airplanes; serial numbers 2001 through 2055, inclusive; certificated in any category.

Compliance: Required as indicated, unless accomplished previously.

To prevent operational failure of the fire extinguisher systems for the left- and right-hand engines, accomplish the following:

(a) Within 14 days after the effective date of this AD, perform a safety ohmmeter inspection to verify the electrical conductivity of the firing circuits at the cartridge connectors of the fire extinguisher bottles of the left- and right-hand engines in accordance with Jetstream Aircraft, Ltd., Service Bulletin ATP-26-9, dated May 12, 1993.

(1) If an out-of-tolerance condition is not detected: No further action is required by this paragraph.

NOTE: An "out-of-tolerance condition" is defined as having an electrical resistance reading of less than 5.5 ohms or greater than 7 ohms.

(2) If an out-of-tolerance condition is detected: Prior to further flight, perform a full electrical inspection of the fire extinguisher systems of the left- and right-hand engines and repeat the safety ohmmeter inspection in accordance with the service bulletin.

(i) If an out-of-tolerance condition is no longer detected: No further action is required by this paragraph.

(ii) If an out-of-tolerance condition is still detected: Prior to further flight, replace the cartridge firing unit with a new or serviceable cartridge firing unit and/or replace the cartridge connector with a new or serviceable cartridge connector in accordance with the service bulletin.

(b) Within 10 days after accomplishing the inspection(s) required by paragraph (a) of this AD, submit a report of any inspection findings, to Jetstream Aircraft, Ltd., in accordance with Jetstream Aircraft, Ltd., Service Bulletin ATP-26-9, dated May 12, 1993. Report all findings, including nil defects, to: Service Support Manager, Customer Support Department, Jetstream Aircraft, Ltd., Woodford Aerodrome, Chester Road, Cheshire SK7 1QR, England. Information collection requirements contained in this regulation 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.

(c) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Standardization Branch, ANM-113, FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Standardization Branch, ANM-113.

NOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

(d) 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.

(e) The inspections and replacement shall be done in accordance with Jetstream Aircraft, Ltd., Service Bulletin ATP-26-9, dated May 12, 1993. 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 Jetstream Aircraft, Inc., P.O. Box 16029, Dulles International Airport, Washington, DC 20041-6029. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(f) This amendment becomes effective on July 19, 1993.