88-20-08 HAMILTON STANDARD: Amendment 39-6009. Applies to Hamilton Standard Model 14SF-5 and 14SF-7 propellers equipped with plastic "Rynite" retaining rings, P/N 785540, installed on, but not limited to, Dehavilland Dash 8 and Aerospatiale/ Aeritalia ATR-42 aircraft.
Compliance is required as indicated, unless already accomplished.
To prevent loss of the plastic "Rynite" blade retaining rings, P/N 785540, and severe damage to the blade retention system with resultant propeller unbalance, accomplish the following:
(a) Within the next 50 hours time in service after May 21, 1987, and thereafter at intervals not to exceed 200 hours time in service, until accomplishment of paragraph (c), inspect the plastic "Rynite" blade retaining rings, P/N 785540, on all four blades in accordance with Hamilton Standard Alert Service Bulletin (ASB) 14SF-61-A21, Revision 2, dated March 27, 1987.
(b) If any evidence of cracks is discovered as a result of an inspection required by paragraph (a), prior to further flight remove from service both halves of blade retaining rings and replace with new or serviceable retaining ring halves in accordance with Hamilton Standard ASB 14SF-61-A21, Revision 2, dated March 27, 1987, or accomplish paragraph (c) below prior to further flight.
(c) Replace, not later than July 31, 1989, the plastic "Rynite" blade retaining rings, P/N 785540, with aluminum blade retaining rings, P/N 794345, on all four blades in accordance with Hamilton Standard Service Bulletin 14SF-61-17, Revision 1, dated October 1, 1987.
(d) Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 to a base where the AD can be accomplished.
(e) Upon request, an equivalent means of compliance with the requirements of this AD may be approved by the Manager, Boston Aircraft Certification Office, Engine and Propeller Directorate, Aircraft Certification Service, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803.
(f) Upon submission of substantiating data by an owner or operator through an FAA Airworthiness Inspector, the Manager, Boston Aircraft Certification Office, may adjust the compliance time specified in this AD.
Hamilton Standard ASB 14SF-61-A21, Revision 2, dated March 27, 1987, and ASB 14SF-61-17, Revision 1, dated October 1, 1987, identified and described in this document, are incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received these documents from the manufacturer may obtain copies upon request to Hamilton Standard Division of United Technologies Corporation, Windsor Locks, Connecticut 06096. These documents may also be examined at the Office of the Assistant Chief Counsel, Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803, Room 311, Docket 87-ANE-13, between the hours of 8:00 a.m.and 4:30 p.m., Monday through Friday, except federal holidays.
This amendment, 39-6009, supersedes AD 87-10-05, Amendment 39-5609.
This amendment, 39-6009, becomes effective on October 31, 1988.