AD 96-01-01 SUPERSEDED

This amendment adopts a new airworthiness directive (AD) that is applicable to Hamilton Standard Propeller 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. This action supersedes priority letter AD 95-18-06 R1, that was issued on August 30, 1995, that currently requires ultrasonic shear wave inspection on all Hamilton Standard 14RF-9 propeller blades, and ultrasonic shear wave inspection on certain Hamilton Standard Propeller 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. This action requires that all blades of applicable Hamilton Standard propellers be calibrated for ultrasonic transmissibility before conducting the ultrasonic shear wave inspection. This action improves the crack detection capability of the ultrasonic shear wave inspection.This action also decreases the repetitive inspection interval for the 14RF-9, 14SF-5, -7, -11, -15, -17, -19, and -23 from 1,250 flight cycles to 500 flight cycles. This action also establishes a new ultrasonic shear wave inspection interval of 1,000 flight cycles for the 14RF-19 and 2,500 flight cycles for the 14RF-21 and the 6/5500/F. This AD also removes 14SFL11 propellers from service. This AD is prompted by reports that the existing ultrasonic shear wave inspection may not detect cracks as originally determined with some blades due to geometric differences. The actions specified by this AD are intended 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 the aircraft.

96-01-01 HAMILTON STANDARD: Amendment 39-9477. Docket No. 95-ANE-73. Supersedes AD 95-18-06 R1, issued August 30, 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, EMB-120RT; Aerospatiale ATR42-100, ATR42-300, ATR42-320, ATR72, ATR72-210; de Havilland DHC-8-100 series, DHC-8-200 series, DHC-8-300 series; SAAB-SCANIA SF 340B; Canadair CL-215T, CL-415; Construcciones Aeronauticas SA (CASA) CN-235 series; and British Aerospace ATP aircraft.. NOTE: This airworthiness directive (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 (n) 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, with Serial Numbers less than 882038 and listedin Hamilton Standard Alert Service Bulletins (ASB's) No. 14RF-9-61-A95, dated December 18, 1995, or No. 14RF-9-61-A95, Rev 1, dated December 21, 1995, installed on but not limited to Embraer EMB-120 and EMB-120RT series aircraft, accomplish the following:

(1) Within the next 150 flight cycles, after the effective date of this AD, perform an ultrasonic shear wave inspection for cracks in the blade taper bore in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-9-61-A95, dated December 18, 1995, or No. 14RF-9-61-A95, Rev 1, dated December 21, 1995.

(2) For propeller blades that have been previously inspected in accordance with Hamilton Standards ASB's No. 14RF-9-61-A91, dated December 7, 1995, or No. 14RF-9-61-A91, Rev 1, dated December 15, 1995, perform an ultrasonic shear wave inspection in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-9-61-A95, dated December 18, 1995, or No. 14RF-9-61-A95, Rev 1, dated December 21, 1995, within 500 flight cycles since last inspection or 150 flight cycles after the effective date of this AD, whichever occurs later.

(3) Propeller blades that cannot be inspected for cracks in accordance with Hamilton Standard ASB's No. 14RF-9-61-A95, dated December 18, 1995, or No. 14RF-9-61-A95, Rev 1, dated December 21, 1995, due to the lead wool absorbing the ultrasonic signal, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-9-61-A91, dated December 7, 1995, or No. 14RF-9-61-A91, Rev 1 dated December 15, 1995, within the next 150 flight cycles after the effective date of this AD.

(4) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14RF-9-61-A95, dated December 18, 1995, or No. 14RF- 9-61-A95, Rev 1, dated December 21, 1995, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-9-61-A91 dated December 7, 1995, or No. 14RF-9-61-A91, Rev 1 dated December 15, 1995.

(5) Thereafter, perform repetitive ultrasonic shear wave inspections at intervals not to exceed 500 flight cycles in accordance with the applicable SB's.

(6) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14RF-9-61-A91, dated December 7, 1995, or No. 14RF-9- 61-A91, Rev 1, dated December 15, 1995, must be removed from service, and replaced with a serviceable part prior to further flight.

(b) For Hamilton Standard Models 14SF-5, -7, -11, -15, and -23 propeller blades with Serial Numbers less than 882038 and listed in Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95, Rev 1, dated December 21, 1995, installed on but not limited to Aerospatiale ATR42-100, ATR42-300, ATR42-320, ATR72 and de Havilland DHC-8-100, DHC-8-200, DHC-8-300 series aircraft, accomplish the following:

(1) Within the next 150 flight cycles, after the effective date of this AD, perform an ultrasonic shear wave inspection for cracks in the blade taper bore in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95, Rev 1, dated December 21, 1995.

(2) For propeller blades that have been previously inspected in accordance with Hamilton Standards ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF-61-A93, Rev 1, dated December 15, 1995, perform an ultrasonic shear wave inspection in accordance with the Accomplishments Instructions of Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95, Rev 1, dated December 21, 1995, within 500 flight cycles since last inspection or 150 flight cycles after the effective date of this AD, whichever occurs later.

(3) Propeller blades that cannot be inspected for cracks in accordance with Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95, Rev 1, dated December 21, 1995, due to the lead wool absorbing the ultrasonic signal, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF-61-A93, Rev 1, dated December 15, 1995, within the next 150 flight cycles after the effective date of this AD.

(4) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61- A95, dated December 21, 1995, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF- 61-A93, Rev 1, dated December 15, 1995.

(5) Thereafter, perform repetitive ultrasonic shear wave inspections at intervals not to exceed 500 flight cycles in accordance with the applicable SB's.

(6) Propeller blades thathave ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF-61- A93, Rev 1, dated December 15, 1995, must be removed from service and replaced with a serviceable part prior to further flight.

(c) For Hamilton Standard Model 14RF-9 propeller blades with Serial Numbers less than 882038 and not listed in Hamilton Standard ASB's No. 14RF-9-61-A95, dated December 18, 1995, or No. 14RF-9-61-A95, Rev 1, dated December 21, 1995, installed on but not limited to Embraer EMB 120 and EMB 120RT series aircraft, accomplish the following:

(1) Within the next 300 flight cycles, after the effective date of this AD, perform an ultrasonic shear wave inspection for cracks in the blade taper bore in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-9-61-A95, dated December 18, 1995, or No. 14RF-61-A95, Rev 1, dated December 21, 1995.

(2) For propeller blades that have been previously inspected in accordance with Hamilton Standards ASB's No. 14RF-9-61-A91, dated December 7, 1995, or No. 14RF-9-61-A91, Rev 1, dated December 15, 1995, perform an ultrasonic shear wave inspection in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-9-61-A95, dated December 18, 1995, or No. 14RF-9-61-A95, Rev 1, dated December 21, 1995, within 300 flight cycles since last inspection or 150 flight cycles after the effective date of this AD, whichever occurs later.

(3) Propeller blades that cannot be inspected for cracks in accordance with Hamilton Standard ASB's No. 14RF-9-61-A95, dated December 18, 1995, or No. 14RF-9-61-A95, Rev. 1, dated December 21, 1995, due to the lead wool absorbing the ultrasonic signal, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-9-61-A91, dated December 7, 1995, or No. 14RF-9-61-A91, Rev. 1, dated December 15, 1995, within the next 300 flightcycles after the effective date of this AD.

(4) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14RF-9-61-A95, dated December 18, 1995, or No. 14RF- 9-61-A95, dated December 21, 1995, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-9-61-A91, dated December 7, 1995, or No. 14RF-9-61-A91 Rev. 1, dated December 15, 1995.

(5) Thereafter, perform repetitive ultrasonic shear wave inspections at intervals not to exceed 500 flight cycles in accordance with the applicable SB's.

(6) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14RF-9-61-A91, dated December 7, 1995, or No. 14RF-9- 61-A91, Rev. 1, dated December 15, 1995, must be removed from service and replaced with a serviceable part prior to further flight.

(d) For Hamilton Standard Models 14SF-5, -7, -11, -15,-17, -19, and -23 propeller blades with Serial Numbers less than 882038 and not listed in ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95, Rev. 1, dated December 21, 1995, installed on but not limited to Aerospatiale ATR42-100, ATR42-300, ATR42-320, ATR72, ATR72-210 and de Havilland DHC-8-100, DHC-8-200, DHC-8-300 series aircraft, accomplish the following:

(1) Within the next 300 flight cycles, after the effective date of this AD, perform an ultrasonic shear wave inspection for cracks in the blade taper bore in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95 Rev. 1, dated December 21, 1995.

(2) For propeller blades that have been previously inspected in accordance with Hamilton Standards ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF-61-A93, Rev. 1, dated December 15, 1995, perform an ultrasonic shear wave inspection in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95, Rev. 1, dated December 21, 1995, within 500 flight cycles since last inspection or 300 flight cycles after the effective date of this AD, whichever occurs later.

(3) Propeller blades that cannot be inspected for cracks in accordance with Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95, Rev. 1, dated December 21, 1995, due to the lead wool absorbing the ultrasonic signal, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF-61-A93, Rev. 1, dated December 15, 1995, within the next 300 flight cycles after the effective date of this AD.

(4) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61- A95, Rev. 1, dated December 21,1995, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF- 61-A93, Rev. 1, dated December 15, 1995.

(5) Thereafter, perform repetitive ultrasonic shear wave inspections at intervals not to exceed 500 flight cycles in accordance with the applicable SB's.

(6) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF-61- A93, Rev. 1, dated December 15, 1995, must be removed from service and replaced with a serviceable part prior to further flight.

(e) For all Hamilton Standard Models 14SF-17, and -19 propeller blades with Serial Numbers less than 882038, installed on but not limited to Canadair CL-215T and CL-415 series aircraft, accomplish the following:

(1) Within the next 300 flight cycles, after the effective date of this AD, perform an ultrasonic shearwave inspection for cracks in the blade taper bore in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95, Rev. 1, dated December 21, 1995.

(2) For propeller blades that have been previously inspected in accordance with Hamilton Standards ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF-61-A93, Rev. 1, dated December 15, 1995, perform an ultrasonic shear wave inspection in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95, Rev. 1, dated December 21, 1995, within 500 flight cycles since last inspection or 300 flight cycles after the effective date of this AD, whichever occurs later.

(3) Propeller blades that cannot be inspected for cracks in accordance with Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95, Rev. 1, dated December 21, 1995, due to the lead wool absorbing the ultrasonic signal, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A93 dated December 7, 1995, or No. 14SF-61-A93, Rev. 1, dated December 15, 1995, within the next 300 flight cycles after the effective date of this AD.

(4) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61- A95 Rev. 1, dated December 21, 1995, must be removed from service and inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF-61-A93 Rev. 1, dated December 15, 1995.

(5) Thereafter, perform repetitive ultrasonic shear wave inspections at intervals not to exceed 500 flight cycles in accordance with the applicable SB's.

(6) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF-61- 93, Rev. 1, dated December 15, 1995, must be removed from service and replaced with a serviceable part prior to further flight.

(f) For all Hamilton Standard Models 14RF-19 propeller blades with Serial Numbers less than 882038, installed on but not limited to SAAB-SCANIA SF 340B series aircraft, accomplish the following:

(1) Within the next 300 flight cycles, after the effective date of this AD, perform an ultrasonic shear wave inspection for cracks in the blade taper bore in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-19-61-A57, dated December 18, 1995, or No. 14RF-19-61-A57, Rev. 1, dated December 21, 1995.

(2) For propeller blades that have been previously inspected in accordance with Hamilton Standards ASB's No. 14RF-19-61-A55, dated December 7, 1995, or No. 14RF-19-61-A55, Rev. 1, dated December 15, 1995, perform an ultrasonic shear wave inspection in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-19-61-A57, dated December 18, 1995, or No. 14RF-19-61-A57 Rev. 1, dated December 21, 1995, within 1,000 flight cycles since last inspection or 300 flight cycles after the effective date of this AD, whichever occurs later.

(3) Propeller blades that cannot be inspected for cracks in accordance with Hamilton Standard ASB's No. 14SF-61-A95, dated December 18, 1995, or No. 14SF-61-A95 Rev. 1, dated December 21, 1995, due to the lead wool absorbing the ultrasonic signal inspect in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14SF-61-A93, dated December 7, 1995, or No. 14SF-61-A93, Rev. 1, dated December 15, 1995, within the next 300 flight cycles after the effective date of this AD.

(4) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's 14RF-19-61-A57, dated December 18, 1995, or No. 14RF-19- 61-A57, Rev. 1, dated December 21, 1995, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-19-61-A55, dated December 7, 1995, or No. 14RF-19-61-A55, Rev. 1, dated December 15, 1995.

(5) Thereafter, perform repetitive ultrasonic shear wave inspections at intervals not to exceed 1,000 flight cycles in accordance with the applicable SB's.

(6) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14RF-19-61-A55, dated December 7, 1995, or No. 14RF- 19-61-A55, Rev. 1, dated December 15, 1995, must be removed from service and replaced with a serviceable part prior to further flight.

(g) For all Hamilton Standard Model 14RF-21 propeller blades with Serial Numbers less than 882038, installed on but not limited to Construcciones Aeronautic SA (CASA) CN-235 series aircraft, accomplish the following:

(1) Within the next 300 flight cycles, after the effective date of this AD, perform an ultrasonic shear wave inspection for cracks in the blade taper bore in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-21-61-A75, dated December 18, 1995, or No. 14RF-61-A75, Rev. 1, dated December 21, 1995.

(2) For propeller blades that have been previously inspected in accordance with Hamilton Standards ASB's No. 14RF-19-61-A55, dated December 7, 1995, or No. 14RF-19-61-A55, Rev. 1, dated December 15, 1995, perform an ultrasonic shear wave inspection in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-19-61-A57, dated December 18, 1995, or No. 14RF-19-61-A57, Rev. 1, dated December 21, 1995, within 1,000 flight cycles since last inspection or 300 flight cycles after the effective date of this AD, whichever occurs later.

(3) Propeller blades that cannot be inspected for cracks in accordance with Hamilton Standard ASB's No. 14RF-21-61-A75, dated December 18, 1995,or No. 14RF-61-A75, Rev. 1, dated December 21, 1995, due to the lead wool absorbing the ultrasonic signal, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-21-61- A73, dated December 7, 1995, or No. 14RF-21-61-A73, Rev. 1, dated December 15, 1995, within the next 300 flight cycles after the effective date of this AD.

(4) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14RF-21-61-A75, dated December 18, 1995, or No. 14RF- 21-61-A75, Rev. 1, dated December 21, 1995, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 14RF-21-61-A73, dated December 7, 1995, or No. 14RF-21-61-A73, Rev. 1, dated December 18, 1995.

(5) Thereafter, perform repetitive ultrasonic shear wave inspections at intervals not to exceed 2,500 flight cycles in accordance with the applicable SB's.

(6) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 14RF-21-61-A73, dated December 7, 1995, or No. 14RF- 21-61-A73, Rev. 1, dated December 18, 1995, must be removed from service and replaced with a serviceable part prior to further flight.

(h) For all Hamilton Standard/British Aerospace 6/5500/F propeller blades, with Serial Numbers less than 882038, installed on but not limited to British Aerospace ATP series aircraft, accomplish the following:

(1) Within the next 300 flight cycles, after the effective date of this AD, perform an ultrasonic shear wave inspection for cracks in the blade taper bore in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 6/5500/F-61-A43, dated December 18, 1995, or No. 6/5500/F-61-A43, Rev. 1, dated December 21, 1995.

(2) For propeller blades that have been previously inspected in accordance with Hamilton Standards ASB's No. 6/5500/F-61-A41, dated December 7, 1995, or No. 6/5500/F-61- A41, Rev. 1, dated December 18, 1995, perform an ultrasonic shear wave inspection in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 6/5500/F-61-A43, or No. 6/5500/F-61-A43, Rev. 1, dated December 21, 1995, as applicable within 2,500 flight cycles since last inspection or 300 flight cycles after the effective date of this AD, whichever occurs later.

(3) Propeller blades that cannot be inspected for cracks in accordance with Hamilton Standard ASB's No. 6/5500/F-61-A43, dated December 18, 1995, or No. 6/5500/F-61-A43, Rev. 1, dated December 21, 1995, due to the lead wool absorbing the ultrasonic signal, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 6/5500/F-61- A41, dated December 7, 1995, or No. 6/5500/F-61-A41, Rev. 1, dated December 18, 1995, within the next 300 flight cycles after the effective date of this AD.

(4) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 6/5500/F-61-A43, dated December 18, 1995, or No. 6/5500/F-61-A43, Rev. 1, dated December 21, 1995, must be inspected in accordance with the Accomplishment Instructions of Hamilton Standard ASB's No. 6/5500/F-61-A41, dated December 7, 1995, or No. 6/5500/F-61-A41 Rev. 1, dated December 18, 1995.

(5) Thereafter, perform repetitive ultrasonic shear wave inspections at intervals not to exceed 2,500 flight cycles in accordance with the applicable SB's.

(6) Propeller blades that have ultrasonic shear wave indications that exceed the limits specified in Hamilton Standard ASB's No. 6/5500/F-61-A41, dated December 7, 1995, or No. 6/5500/F-61-A41, Rev. 1, dated December 18, 1995, must be removed from service and replaced with a serviceable part prior to further flight.

(i) For all currently installed Hamilton Standard Model 14SFL11 propellers installed on Aerospatiale ATR72-210 series aircraft remove all 14SFL11 propellers from service within the next 150 flight cycles, after the effective date of this AD, and replace with serviceable Hamilton Standard 247F propellers.

(j) The ultrasonic inspection of the propeller blade taper bore must be performed by a Level II inspector who is qualified under the guidelines established by the American Society of Nondestructive Testing or MIL-STD-410 or FAA approved equivalent, and must be trained by Hamilton Standard approved personnel on how to do this inspection procedure. The individual returning the aircraft to service is required to verify that the ultrasonic inspection was accomplished in accordance with the requirements of this paragraph.

(k) For repetitive inspections, propeller blades may be evaluated to determine if the lead wool is absorbing the ultrasonic signal at any time during the 500 flight cycle repetitive inspection interval to determine if the lead wool removal is required to complete the ultrasonic shear wave inspection.

(l) 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.

(m) Propeller blades removed from service after inspections performed in accordance with AD 95-18-06 R1, and subsequently inspected in accordance with the requirements of this AD and found to be serviceable, may be returned to service.

(n) 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 thisairworthiness directive, if any, may be obtained from the Boston Aircraft Certification Office.

(o) Special flight permits may be issued in accordance with sections 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.

(p) The ultrasonic shear wave inspections and removal and replacement of propeller blades shall be done in accordance with the following Hamilton Standard Alert Service Bulletins:

DOCUMENT NO.
REVISION
DATE
No. 14RF-9-61-A91
Total Pages: 40

December 7, 1995
No. 14RF-9-61-A91
Total Pages: 42
1
December 15, 1995
No. 14RF-19-61-A55
Total Pages: 40

December 7, 1995
No. 14RF-19-61-55
Total Pages: 42
1
December 15, 1995
No. 14RF-21-61-A73
Total Pages: 40

December 7, 1995
No. 14RF-21-61-A73
Total Pages: 42
1
December 15, 1995
No. 14SF-61-A93
Total Pages: 40

December 7, 1995
No. 14SF-61-A93
Total Pages: 42
1
December 15, 1995
No. 6/5500/F-61-A41
Total Pages: 40

December 7, 1995
No. 6/5500/F-61-A41
Total Pages: 42
1
December 15, 1995
No. 14RF-9-61-A95
Total Pages: 36

December 18, 1995
No. 14RF-9-61-A95
Total Pages: 36
1
December 21, 1995
No. 14RF-19-61-A57
Total Pages: 35

December 18, 1995
No. 14RF-19-61-A57
Total Pages: 35
1
December 21,1995
No. 14RF-21-61-A75
Total Pages: 35

December 18, 1995
No. 14RF-21-61-A75
Total Pages: 35
1
December 21,1995
No. 14SF-61-A95
Total Pages: 37

December 18, 1995
No. 14SF-61-A95
Total Pages: 37
1
December 21, 1995
No. 6/5500/F-61-A43
Total Pages: 35

December 18, 1995
No. 6/5500/F-61-A43
Total Pages: 35
1
December 21, 1995

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, One Hamilton Road, Windsor Locks, CT 06096-1010; telephone (203) 654-6876. This information 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.

(q) This amendment supersedes priority letter AD 95-18-06 R1, issued August 30, 1995. Note: AD 95-18-06 R1 revised priority letter 95-18-06, which superseded telegraphic AD T95-18-51 and AD 95-05-03. Also, AD 95-05-03 superseded 94-09-06.

(r) This amendment becomes effective on January 19, 1996.

On August 30, 1995, the Federal Aviation Administration (FAA) issued priority letter airworthiness directive (AD) 95-18-06 R1 applicable to Hamilton Standard Propeller 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, which requires ultrasonic shear wave inspection on all Hamilton Standard 14RF-9 propeller blades, and ultrasonic shear wave inspection on certain Hamilton Standard Models 14RF-19, -21; and 14SF-5, -7, -11, L11, -15, -17, -19, and 23; and Hamilton Standard/British Aerospace 6/5500/F propeller blades. That AD action was prompted by a report of a Hamilton Standard 14RF-9 propeller blade installed on an Embraer EMB-120 aircraft that had separated inflight.

Since the issuance of that priority letter AD, the FAA and Hamilton Standard have been working to improve the crack detection capability of the ultrasonic inspection method as well as working to refine the crack growth rate prediction methodology. The results of this work form the basis for the new inspection method and the change in repetitive inspection interval. This AD will require that propeller blades be calibrated for ultrasonic transmissibility before conducting an ultrasonic shear wave inspection, thereby improving the detection capability of the ultrasonic shear wave inspection technique. This action will also decrease the repetitive inspection interval for the 14RF-9, 14SF-5, -7, -11, -15, -17, -19, and -23 from 1,250 flight cycles to 500 flight cycles. This action will further establish a new ultrasonic shear wave inspection interval of 1,000 flight cycles for the 14RF-19 and 2,500 flight cycles for the 14RF-21 and the 6/5500/F propeller models. This AD also requires removal of the life limited 14SFL11 propellers currently in service, approximately four propellers. These 14SFL11 propellers will be replaced with the Hamilton Standard Model 247F propellers. The actions specified by this AD are intended to prevent the 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.

This AD references two ultrasonic inspection methods, one that can be accomplished without removing the lead from the taper bore which permits an on wing inspection and a second inspection that requires the blade be removed and inspected at an FAA approved facility. The inspection that is conducted without removing the lead from the taper bore cannot be accomplished on some blades because of ultrasonic transmissibility problems caused by the lead wool absorbing the signal. These blades, must be removed and inspected at an FAA approved facility where the lead wool will be extracted.

The FAA has reviewed and approved the technical contents of the following Hamilton Standard Alert Service Bulletins (ASB's): No. 14RF-9-61-A91, No. 14RF-19-61-A55, No. 14RF-21-61-A73, No. 14SF-61-A93, and No. 6/5500/F-61-A41, all dated December 7, 1995, and No. 14RF-9-61-A91, Rev 1, No. 14RF-19-61-A55, Rev 1, No. 14RF-21-61-A73, Rev 1, No. 14SF-61-A93, Rev 1, and No. 6/5500/F-61-A41, Rev 1, all dated December 15, 1995, that describe procedures for ultrasonic shear wave inspections of the blade taper bores for cracks after the lead wool has been removed. The Rev. 1 ASB's permit the installation of a plastic cone in the taper bore that will enhance resistance to corrosion and mechanical damage. Inspection procedures are the same.

In addition the FAA has approved ASB's No. 14RF-9-61-A95, No. 14RF-19-61-A57, No. 14RF-21-61-A75, No. 14SF-61-A95, and No. 6/5500/F-61-A43, all dated December 18, 1995, and No. 14RF-9-61-A95, Rev 1, No. 14RF-19-61-A57, Rev 1, No. 14RF-21-61-A75, Rev 1, No. 14SF-61-A95, Rev 1, and No. 6/5500/F-61-A43, Rev 1, all dated December 21, 1995, that describe ultrasonic shear wave inspection that can be accomplished without removing the lead from the taper bore which permits an on-wing inspection of the blade taper bores for cracks. The Rev. 1 ASB's do not require immediate removal of the blades that cannot be inspected for cracks due to the lead wool absorbing the ultrasonic signal. These blades may be removed at any time within the applicable compliance period. Inspection procedures are the same.

Since an unsafe condition has been identified that is likely to exist or develop on other propellers of this same type design, this AD supersedes priority letter AD 95-18-06R1 to require all Hamilton Standard Model 14RF-9, -19, -21; and 14SF-5, -7, -11, -15, -17, -19, and -23; and Hamilton Standard/British Aerospace 6/5500/F propeller blades be calibrated for ultrasonic transmissibility before conducting an ultrasonic shear wave inspection. The actions and inspection intervals for each propeller model are required to be accomplished in accordance with the service bulletins described previously.Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effective in less than 30 days.

Comments Invited

Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this rule by submitting such written data, views, or arguments as they may desire. Communications should identify the Rules Docket number and be submitted in triplicate to the address specified under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestionsis extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.

Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the rule that might suggest a need to modify the rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this notice must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 95-ANE-73." The postcard will be date stamped and returned to the commenter.

The regulations adopted herein will not have substantial direct effects on the States, on the relationship between the national government and the States, or on the distribution of power and responsibilities among the various levels of government. Therefore, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES."

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:
PART 39 - AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
Authority: 49 USC 106(g), 40101, 40113, 44701.
39.13 - [AMENDED]
2. Section 39.13 is amended by adding the following new airworthiness directive:

Submit comments in triplicate to the Federal Aviation Administration (FAA), New England Region, Office of the Assistant Chief Counsel, Attention: Rules Docket No. 95-ANE-73, 12 New England Executive Park, Burlington, MA 01803-5299.
The service information referenced in this AD 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; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

Frank Walsh, Aerospace Engineer, Boston Aircraft Certification Office, FAA, Engine & Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803 telephone (617) 238-7152, fax: (617) 238-7199.