AD 93-06-06 ACTIVE

93-06-06 HAMILTON STANDARD: Amendment 39-8531. Docket No. 92-ANE-51.

Applicability: Hamilton Standard Models 14RF-9, 14RF-19, and 14RF-21, and Models 14SF-5, 14SF-7, 14SF-11, 14SF-15, 14SF-17, 14SF-19, and 14SF-23 propellers, and Hamilton Standard-British Aerospace Model 6/5500/F-1 propellers installed on but not limited to Embraer EMB-120 and EMB-120RT; SAAB-SCANIA AB SAAB 340B; Aerospatiale ATR42-100, ATR42-300, ATR42-320, ATR72-101, ATR72-210; DeHavilland DHC-8-100, DHC-8-300, DHC-8-314; Construcciones Aeronauticas SA (CASA) CN-235 and CN-235-100; Canadair CL215T; and British Aerospace ATP airplanes.

Compliance: Required as indicated, unless accomplished previously.

To prevent loss of control of the propeller blade pitch due to propeller control unit (PCU) ballscrew quill wear, accomplish the following:

(a) Within 10 hours time in service (TIS) after the effective date of this AD, for propeller assemblies equipped with titanium nitrided transfer tubes (identifiable by gold-colored spline area), remove the titanium nitrided transfer tubes from service, replace the PCU ballscrew quill with a new quill or a quill that has never been mated with a titanium nitrided transfer tube, and install an A-1 nitrided transfer tube (identifiable by a grey-colored spline area) that has been marked in accordance with the applicable SB listed in paragraph (c) of this AD.

(b) Within 30 hours TIS after the effective date of this AD, for propeller assemblies equipped with an A-1 nitrided transfer tube and a PCU ballscrew quill that either has been mated to a titanium nitrided transfer tube, or that have no records showing to which transfer tube type the PCU ballscrew quill was mated, replace the PCU ballscrew quill with a new quill or a quill that has never been mated with a titanium nitrided transfer tube.

(c) Within 60 days after the effective date of this AD, mark all A-1 nitrided transfer tubes with a new part number in accordance with the following Hamilton Standard Alert Service Bulletins (ASB), all dated October 27, 1992: ASB No. 14RF-21-61-A39, applicable to Hamilton Standard Model 14RF-21 propellers; ASB No. 14RF-9-61-A57, applicable to Hamilton Standard Model 14RF-9 propellers; ASB No. 14RF-19-61-A26, applicable to Hamilton Standard Model 14RF-19 propellers; ASB No. 14SF-61-A61, applicable to Hamilton Standard 14SF series propellers; and ASB No. 6/5500/F-61-A12, applicable to Hamilton Standard-British Aerospace Model 6/5500/F-1 propellers.

(d) 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 Maintenance Inspector, who may add comments and then send it to the Manager, Boston Aircraft 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.

(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 replacement, and marking of transfer tubes shall be accomplished in accordance with the following service documents:

Document No.
Page
Issue
Date
Hamilton Standard
ASB No.
14RF-21-61-A39
1-7
Original
October 27, 1992
Total pages: 7

Hamilton Standard
ASB No.
14RF-9-61-A57
1-7
Original
October 27, 1992
Total pages: 7

Hamilton Standard
ASB No.
14RF-19-61-A26
1-6
Original
October 27, 1992
Total pages: 6

Hamilton Standard
ASB No.
14SF-61-A61
1-7
Original
October 27, 1992
Total pages: 7

Hamilton Standard
ASB No.
6/5500/F-61-A12
1-7
Original
October 27, 1992
Total pages: 7

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 Hamilton Standard Division of United Technologies Corporation, One Hamilton Road, Windsor Locks, Connecticut 06096-1010. Copies may be inspected at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, Massachusetts; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(g) This amendment supersedes AD T91-11-51 issued on May 22, 1991.

(h) This amendment becomes effective on July 6, 1993.