AD 93-19-01 ACTIVE

93-19-01 Dowty Rotol (now Dowty Aerospace Gloucester Ltd.): Amendment 39-8694. Docket 93-ANE-10. Supersedes AD 87-21-51, Amendment 39-5929.

Applicability: Dowty Rotol (now Dowty Aerospace Gloucester Ltd.) Propeller Models (c)R354/4-123-F/13, (c)R354/4-123-F/20, and (c)R375/4-123-F/21 installed on SAAB-SF340A, and SAAB-SF340B series aircraft.

Compliance: Required as indicated, unless accomplished previously.

To prevent possible loss of the propeller, accomplish the following:

(a) For Dowty Rotol (now Dowty Aerospace Gloucester Ltd.) Model (c)R354/4- 123-F/13 propellers, perform Dowty Aerospace Gloucester Ltd. Modification (C) VP3336 by installing interface shim Part Number (P/N) 660712669 in accordance with Dowty Aerospace Gloucester Ltd. Service Bulletin (SB) No. SF340-61-57, dated February 15, 1991, within 500 hours time in service (TIS) since the last torque check and inspections accomplished in accordance with AD 87-21-51.

(b) For Dowty Rotol (now Dowty Aerospace Gloucester Ltd.) Model R354/4- 123-F/13 propellers, perform a torque check of the propeller retention bolts for low torque and a magnetic particle inspection of the propeller retention bolts for cracks; perform dye penetrant, ultrasonic, and eddy current inspections of the propeller hub backface for cracks. If propeller retention bolts or hubs are found to have cracks, remove from service prior to further flight, and replace with serviceable propeller retention bolts and hubs, within 500 hours TIS since the last torque check and cracking inspections accomplished in accordance with AD 87-21-51. These actions must be accomplished in accordance with Dowty Aerospace Gloucester Ltd. SB No. SF340-61-58, Revision 1, dated July 18, 1991.

(c) For Dowty Rotol (now Dowty Aerospace Gloucester Ltd.) Model (c)R354/4- 123-F/20 and (c)R375/4-123-F/21 propellers, perform Dowty Aerospace Gloucester Ltd. Modification (C) VP3336 by installing interface shim P/N 660712669 in accordancewith Dowty Aerospace Gloucester Ltd. SB No. SF340-61-57, dated February 15, 1991, within 100 hours TIS after the effective date of this AD; or 500 hours TIS since the last torque check and inspections accomplished in accordance with Dowty Aerospace Gloucester Ltd. SB No. SF340-61-58, Revision 1, dated July 18, 1991, or Dowty Aerospace Gloucester Ltd. SB No. SF340-61-21, Revision 4, dated October 1, 1987; or 500 hours TIS since new, whichever occurs latest.

(d) For Dowty Rotol (now Dowty Aerospace Gloucester Ltd.) Model (c)R354/4- 123-F/20 and (c)R375/4-123-F/21 propellers, perform a torque check of the propeller retention bolts for low torque; a magnetic particle inspection of the propeller retention bolts for cracks; and dye penetrant, ultrasonic, and eddy current inspections of the propeller hub backface for cracks. Remove from service prior to further flight cracked propeller retention bolts and hubs, and replace with serviceable propeller retention bolts or hubs, within 100 hours TIS after the effective date of this AD; or 500 hours TIS since the last torque check and inspections accomplished in accordance with Dowty Aerospace Gloucester Ltd. SB No. SF340-61-58, Revision 1, dated July 18, 1991, or Dowty Rotol (now Dowty Aerospace Gloucester Ltd.) SB No. SF340-61-21, Revision 4, dated October 1, 1987; or 500 hours TIS since new, whichever occurs latest. These actions must be accomplished in accordance with Dowty Aerospace Gloucester Ltd, SB No. SF340-61-58, Revision 1, dated July 18, 1991.

(e) Thereafter, for propeller models identified in paragraphs (a) and (c) of this AD, perform a torque check of the propeller retention bolts for low torque; a magnetic particle inspection of the propeller retention bolts for cracks; and dye penetrant, ultrasonic, and eddy current inspections of the propeller hub backface for cracks. Remove from service prior to further flight cracked propeller retention bolts and hubs, and replace with serviceable propeller retention bolts or hubs at intervals not to exceed 1500 hours TIS since the last torque check and inspections performed in accordance with paragraphs (b) or (d), as applicable, of this AD. These actions must be accomplished in accordance with Dowty Gloucester Aerospace Ltd. SB No. SF340-61-58, Revision 1, dated July 18, 1991.

(f) Installation of newly designed Dowty Aerospace Gloucester Ltd. propeller hub assembly P/N 660714241 and remarking of the propeller in accordance with Dowty Aerospace Gloucester Ltd. SB No. SF340-61-61, Revision 1, dated October 19, 1992, constitutes terminating action to the inspection requirements of this AD.

(g) 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, Boston Aircraft Certification Office. The request should be forwarded through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, BostonAircraft Certification Office. NOTE: Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Boston Aircraft Certification Office.

(h) 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.

(i) The inspections shall be done in accordance with the following Dowty Aerospace Gloucester service bulletins:

Document No.
Pages
Revision
Date
SF340-61-57
1-5
Original
February 15, 1991
Total pages: 5.

SF340-61-58
1-2
1
July 18, 1991

3-5
Original
February 15, 1991
Appendix A
1-3
Original
February 15, 1991
Appendix B
1-3
Original
February 15, 1991
Appendix C
1-2
1
July 18, 1991

3-4
Original
February 15, 1991
Total pages: 15.

SF340-61-61
1-3
1
October 19, 1992

4-8
Original
September 9, 1992Total pages: 8.

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 Dowty Aerospace Gloucester Ltd., Anson Business Park, Cheltenham Road East, Gloucester GL2 9QN England. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(j) This amendment becomes effective on October 29, 1993.