AD 95-18-06 R1 SUPERSEDED

95-18-06 R1 Hamilton Standard: Priority Letter issued on August 30, 1995. Docket No. 95-ANE-50. Revises Priority Letter 95-18-06, issued August 28, 1995.

Applicability: Hamilton Standard Models 14RF-9, 14RF-19, 14RF-21, and 14SF-5, 14SF-7, 14SF-11, 14SFL11, 14SF-15, 14SF-17, 14SF-19, and 14SF-23; and Hamilton Standard/British Aerospace 6/5500/F propellers installed on but not limited to Embraer EMB-120 and EMB 120-RT; SAAB-SCANIA SF 340B; Aerospatiale ATR42-100, ATR42-300, ATR42-320, ATR72; DeHavilland DHC-8-100 series, DHC-8-300 Series; Construcciones Aeronauticas SA (CASA) CN-235 series and CN-235-100; Canadair CL-215T and CL-415; and British Aerospace ATP airplanes.

NOTE: This AD applies to each propeller identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For propellers that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must use the authority provided in paragraph (h) to request approval from the Federal Aviation Administration (FAA). This approval may address either no action, if the current configuration eliminates the unsafe condition, or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effect of the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any propeller from the applicability of this AD.

Compliance: Required as indicated, unless accomplished previously.

To prevent separation of a propeller blade due to cracks initiating in the blade taper bore, that can result in aircraft damage, and possible loss of aircraft control, accomplish the following:

(a) For Hamilton Standard Model 14RF-9 propeller blades, installed on Embraer EMB-120 series aircraft, within the next 10 flight cycles after the effective date of this AD, remove from service propeller blades that have been ultrasonically shear wave inspected in accordance with AD 94-09-06 or AD 95-05-03, removed from service due to crack indications, and subsequently reworked and returned to service. These propeller blades include, but are not limited to, the following serial numbers:

847598
851646
852085
852561
853151
854530
854535
854838
855014
855042
855196
855859
857375
858696
859824
860589
867590
876707
880245

(b) For Hamilton Standard Models 14RF-19, 14RF-21, and 14SF-5, 14SF-7, 14SF-11, 14SFL11, 14SF-15, 14SF-17, 14SF-19, and 14SF-23; and Hamilton Standard/British Aerospace 6/5500/F propeller blades, installed on aircraft other than Embraer EMB-120 series aircraft, within the next 10 flight cycles after the effective date of this AD, unless inspected previously in accordance with Telegraphic AD T95-18-51, perform an ultrasonic shear wave inspection for cracks in the blade taper bore of propeller blades that have been ultrasonically inspected in accordance with AD 94-09-06 or AD 95-05-03, removed from service due to crack indications, and subsequently reworked and returned to service. Thereafter, at intervals not to exceed 1,250 flight cycles since last inspection, perform an ultrasonic shear wave inspection for cracks in the blade taper bore of propeller blades. Perform the ultrasonic shear wave inspection in accordance with the Accomplishment Instructions of the following Hamilton Standard Alert Service Bulletins (ASB's), as applicable: No. 14RF-21-61-A68, No. 14SF-61-A88, No. 14RF-19-61-A49, No. 6/5500/F-61-A36; all dated August 25, 1995. Remove propeller blades with crack indications from service and replace with serviceable parts.

(c) For Hamilton Standard Model 14RF-9 propeller blades, installed on Embraer EMB-120 series aircraft, not affected by paragraph (a) of this AD, perform ultrasonic shear wave inspections in accordance with the Accomplishment Instructions of Hamilton Standard ASB No. 14RF-9-61- A85, dated August 28, 1995. Remove propeller blades with crack indications from service and replace with serviceable parts:

(1) For propeller blades with 1,250 or more flight cycles since last ultrasonic shear wave inspection on the effective date of this AD, or that have not been ultrasonically shear wave inspected, perform an ultrasonic shear wave inspection for cracks within the next 50 flight cycles after the effective date of this AD.

(2) For propeller blades with less than 1,250 flight cycles since last ultrasonic shear wave inspection on the effective date of this AD, perform an ultrasonic shear wave inspection for cracks within the next 50 flight cycles after the effective date of this AD, or prior to accumulating 1,250 flight cycles, whichever occurs later.

(3) Thereafter, perform repetitive ultrasonic shear wave inspections at intervals not toexceed 1,250 flight cycles since last inspection.

(d) For Hamilton Standard Models 14RF-19, 14RF-21, and 14SF-5, 14SF-7, 14SF-11, 14SFL11, 14SF-15, 14SF-17, 14SF-19, and 14SF-23; and Hamilton Standard/British Aerospace 6/5500/F propeller blades; identified by serial number in the ASB's listed in this paragraph, installed on aircraft other than Embraer EMB-120 aircraft, and not affected by paragraph (b) of this AD, perform ultrasonic shear wave inspections in accordance with the Accomplishment Instructions of Hamilton Standard ASB's, as applicable: No. 14RF-21-61-A69, No. 14SF-61-A89, No. 14RF-19- 61-A50, No. 6/5500/F-61-A37; all dated August 28, 1995. Remove propeller blades with crack indications from service and replace with serviceable parts:

(1) For propeller blades with 1,250 or more flight cycles since last ultrasonic shear wave inspection on the effective date of this AD, or that have not been ultrasonically shear wave inspected, perform an ultrasonic shear wave inspection for cracks within the next 150 flight cycles after the effective date of this AD.

(2) For propeller blades with less than 1,250 flight cycles since last ultrasonic shear wave inspection on the effective date of this AD, perform an ultrasonic shear wave inspection for cracks within the next 150 flight cycles after the effective date of this AD, or prior to accumulating 1,250 flight cycles, whichever occurs later.

(3) Thereafter, perform repetitive ultrasonic shear wave inspections at intervals not to exceed 1,250 flight cycles since last inspection.

(e) No ultrasonic shear wave inspections are required for Hamilton Standard Models 14RF- 19, 14RF-21, and 14SF-5, 14SF-7, 14SF-11, 14SFL11, 14SF-15, 14SF-17, 14SF-19, and 14SF-23; and Hamilton Standard/British Aerospace 6/5500/F propeller blades, that have been shotpeened in the taper bore during manufacture, and not identified by serial numbers in the ASB's listed in paragraph (b) of this AD.

(f) Propeller blades removed from service in accordance with this AD may not be returned to service.

(g) For the purpose of this AD, a flight cycle is defined as one takeoff and the next landing of an aircraft. In addition, each touch and go is defined as a flight cycle, and each water load pick up for amphibian aircraft operation is defined as a flight cycle.

(h) 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, 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.

(i) Special flight permits may be issued in accordance withsections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the aircraft to a location where the requirements of this AD can be accomplished.

(j) Copies of the applicable service information may be obtained from Hamilton Standard, One Hamilton Road, Windsor Locks, CT 06096-1010; telephone (203) 654-6876. This information may be examined at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA.

(k) Priority Letter AD 95-18-06 R1, issued August 30, 1995, becomes effective upon receipt.

(l) Priority Letter AD 95-18-06 R1 revises priority letter 95-18-06 issued August 25, 1995.

This Revised Priority Letter AD 95-18-06 R1 revised Priority Letter AD 95-18-06 issued on August 28, 1995, and supersedes the Telegraphic AD T95-18-51 issued on August 25, 1995.

Frank Walsh, Aerospace Engineer, Boston Aircraft Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone (617) 238-7158, fax (617) 238-7199.