DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39 [SN] [R10/25/50/400H]

[Docket No. 94-ANE-19; Amendment 39-9008; AD 94-17-13] 

Airworthiness Directives; Hartzell Propeller Inc. HC-( )3Y( )-( ) Series Three-Bladed Propellers 

AGENCY: Federal Aviation Administration, DOT. 

ACTION: Final rule; request for comments. 

SUMMARY: This amendment supersedes an existing airworthiness directive (AD), applicable to Hartzell Propeller Inc. HC-( )3Y( )-( ) series three-bladed propellers, that currently requires initial and repetitive visual and eddy current inspections for cracks in the area of the grease fitting holes on the side of the propeller hub arm. This amendment reduces the repetitive inspection interval from 25 hours time in service (TIS) to 10 hours TIS. In addition, this amendment adds an optional interim alternative method of compliance involving a chamfering modification to extend the initial and repetitive inspection compliance interval. This amendment also adds a terminating action to require propeller hub replacement to a new hub configuration where grease fittings are located in a reinforced area near the hub parting line. This amendment is prompted by a report from the Aviation Accident Investigation Board (AAIB) of the United Kingdom and a recent incident that indicates a hub failure could have occurred in less time than the 25 hour TIS inspection interval. The actions specified by this AD are intended to prevent possible propeller hub failure and subsequent propeller blade separation and loss of the aircraft. 

DATES: Effective September 15, 1994. 

	The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of September 15, 1994. 
	Comments for inclusion in the Rules Docket must be received on or before October 31, 1994. 

ADDRESSES: Submit comments in triplicate to the Federal Aviation Administration (FAA), New England Region, Office of the Assistant Chief Counsel, Attention: Rules Docket No. 94-ANE-19, 12 New England Executive Park, Burlington, MA 01803-5299. 

	The service information referenced in this AD may be obtained from Hartzell Propeller Inc., One Propeller Place, Piqua, OH 45356-2834; telephone (513) 778-4200, fax (513) 778-4391. This information may be examined at the FAA, New England Region, Office of the Assistant Chief Counsel, Burlington, MA; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. 

FOR FURTHER INFORMATION CONTACT: Tim Smyth, Aerospace Engineer, Chicago Aircraft Certification Office, FAA, Small Airplane Directorate, 2300 East Devon Avenue, Room 232, Des Plaines, IL 60018; telephone (708) 294-7130, fax (708) 294-7834. 

SUPPLEMENTARY INFORMATION: On October 20, 1989, the Federal Aviation Administration (FAA) issued priority letter airworthiness directive (AD) 89-22-05, to require visual inspection of the propeller hub surface in the area of the grease fittings at intervals of 50 hours time in service (TIS). That action was prompted by reports of propeller hub failures caused by cracks initiating in the grease fitting holes on the side of the hub arm. These cracks typically originate in the threads of the hub grease fitting, then propagate around the blade arm of the hub, resulting in failure of the hub. That condition, if not corrected, could result in possible propeller hub failure and subsequent propeller blade separation and loss of the aircraft. 

	Since the issuance of that AD, the FAA received a report from the Civil Aviation Authority (CAA) of the United Kingdom of a propeller hub failure on a propeller that had been visually inspected in accordance with AD 89-22-05. The CAA's investigation revealed that the propeller hub crack had corrosion on the fracture surface that was present for a considerable time but the crack was undetectable by visual inspection. The FAA, in conjunction with the CAA and the manufacturer, determined that the visual inspection procedure alone is inadequate to reliably find cracks in the propeller hub. On August 18, 1993, the FAA issued priority letter AD 93-16-14, which requires initial and repetitive visual inspections and eddy current inspections (ECI) for cracks in the area of the grease fitting holes on the side of the propeller hub. The FAA issued the final rule on this action on November 22, 1993, which was published in the Federal Register on December 21, 1993 (58 FR 67307). 
	Recently, an inspector found an additional significant hub crack evidenced by grease leaking from the propeller hub. The hub was eddy current inspected and verified that a crack of significant length was present. The hub had been previously inspected using the eddy current inspection process with no crack indications present. A significant crack indication occurred in less time than the current 25 hour TIS inspection interval. Based on this latest service difficulty report, the FAA has determined that it is necessary to reduce the current 25 hour TIS inspection interval to 10 hours TIS for hubs installed on certain aircraft and to mandate replacement of existing designed hubs to the new hub configuration as soon as practical on these aircraft. A total of 24 hub cracks have been found to date. At the present time, over 2,500 propeller hubs have been distributed with the new post-1983 configuration propeller hub. 
	The FAA has reviewed and approved the technical contents of Hartzell Propeller Inc. Service Bulletin (SB) No. 165E, dated January 21, 1994, that describes procedures for visual inspections, and ECI or fluorescent penetrant inspection (FPI), for cracks in the area of the grease fitting holes on the side of the propeller hub. In addition, this SB describes an interim alternative method of compliance that involves chamfering the inside and outside surfaces of the propeller hub arm by the grease fitting holes. This modification allows the propeller to operate for 400 hours TIS, or 36 months after the effective date of this AD, whichever occurs first, before requiring, for propellers installed on certain aircraft, hub replacement with a new post-1983 configuration propeller hub. This modification was created to provide relief to certain aircraft that would have difficulty in complying with the stringent repetitive inspection intervals and could not obtain propeller hub replacement in the near term. This modification was approved by the FAA as an alternative method of compliance to AD 93-16-14, and has been added to this proposed AD as a interim compliance option. Operators that have accomplished this modification in accordance with Hartzell Propeller Inc. SB No. 165E will be given 400 hours TIS, or 36 calendar months after the effective date of this AD, whichever occurs first, prior to mandating hub replacement for propellers installed on certain aircraft. For propellers installed on other aircraft, this modification extends the repetitive inspection interval to 400 hours TIS. 
	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 AD 93-16-14 to reduce the repetitive inspection interval from 25 hours TIS to 10 hours TIS for propellers installed on certain aircraft. The proposed AD would also require for these propellers a mandatory terminating action by June 1995, or for those propellers that have been modified by chamfering, at 400 hours TIS, or 36 calendar months after the effective date of this AD, whichever occurs first, by requiring replacement of the existing pre-1983 configuration hubs with a new post-1983 hub configuration. For affected propellers installed on other aircraft, the chamfering modification extends the repetitive inspection interval to 400 hours TIS, and the replacement of hubs as a terminating action is optional. In addition, the FAA has restricted the special flight permit paragraph to only allow ferry flights to a point where the inspections can be performed, but to disallow ferry flights when a crack is known or suspected. The actions are required to be accomplished in accordance with the service bulletin 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 suggestions is 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 94-ANE-19." 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 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 106(g); and 14 CFR 11.89. 

sec 39.13   [Amended] 

	2. Section 39.13 is amended by removing Amendment 39-8704 (58 FR 67307, December 21, 1993), and by adding a new airworthiness directive, Amendment 39-9008, to read as follows: 

94-17-13 Hartzell Propeller Inc.: Docket No. 94-ANE-19. Supersedes AD 93-16-14, Amendment 39-8704. 

	Applicability: Hartzell Propeller, Inc. HC-( )3Y( )-( ) series three-bladed propellers with model designations and serial number ranges listed as follows: 

Propeller basic hub model				Propeller serial No. range    
                               
PHC-C3YF-1R( ) 					EE1 through EE1461.            
PHC-J3YF-1R( )					FP1 through FP37.              
PHC-L3YF-1R( ) 					FD1 through FD7.               
HC-C3YF-1R( )					EC1 through EC1020.            
HC-C3YK-1R( ) or HC-C3YR-1R( )			DY1 through DY1897.            
HC-C3YK-1( ) 					CT1 through CT101.             
HC-C3YK-2( ) or HC-C3YR-2( ) 			CK1 through CK3510.            
HC-C3YK-4( ) or HC-C3YR-4( ) 			EL1 through EL67.              
HC-E3YK-1( ) or HC-E3YR-1( )			FM1 through FM487.             
HC-E3YK-2( ) or HC-E3YR-2( ) 			DF1 through DF79.              
HC-E3YK-2A( ) or HC-E3YR-2A( ) 		DJ1 through DJ7787.            
HC-F3YK-2( ) or HC-F3YR-2( ) 			DA1 through DA1586.            
HC-F3YK-1( ) or HC-F3YR-1( ) 			DB1 through DB137.             
HC-I3YK-2( ) or HC-I3YR-2( ) 			FS1 through FS32.              

	This airworthiness directive (AD) applies to the above affected propellers when installed on any agricultural aircraft with any engine, or installed on any aircraft utilizing Textron Lycoming TIO-540 or LTIO-540 series reciprocating engines, or IO-540 series reciprocating engines that have a turbocharger added by the airframe manufacturer or have been modified by a Supplemental Type Certificate (STC) to incorporate a turbocharger, or a turbocharger retrofitted to an IO-540 engine by any other means. The known affected propellers are generally installed on, but not limited to, the following aircraft: 

AGRICULTURAL AIRCRAFT Fletcher FU24-950 Cessna A188 Agwagon modified by STC SA895SO Piper PA-36-285 and PA-36-300 (three-bladed propellers only) Piper PA-36-375 Piper PA-36 Pawnee modified by STC SA3952WE Transavia Airtruk Models and PL-12/T-300 Skyfarmer Aircraft With Textron Lycoming TIO-540, LTIO-540, and Turbocharged IO-540 Series Engines Cessna 310 and 320 modified by Riley STC SA2082WE Gulfstream 700 (formerly Rockwell 700, Fuji FA-300-12) Helio H-700 Piper PA-23-250 and PA-E23-250 (with TIO-540 only) Piper PA-31 Navajo (with TIO-540 only) Piper PA-31-325 Navajo C/R Piper PA-31-350 Navajo "Chieftain" Piper PA-31P-350 Mohave Piper T-1020 (same as PA-31-350) Piper PA-32(R)-301T Turbo Saratoga Aerostar PA-60-600, PA-60-601, PA-60-601P, PA-60-602P, and PA-60-700P. 

	Propellers with model designations and serial number ranges listed above and installed on non-agricultural aircraft, which do not utilize Textron Lycoming TIO-540, LTIO-540, or turbocharged IO-540 series engines are exempt from this AD. 
	Propellers with new post-1983 hub configurations, i.e., which have the relocated grease fitting holes near the hub parting line as shown in Figure 1, page 9, of Hartzell Propeller, Inc., Service Bulletin (SB) No. 165E, dated January 21, 1994, even though the propeller model and serial number are listed above, are exempt from this AD. 
	Compliance: Required as indicated, unless accomplished previously. 
	To prevent possible propeller hub failure due to cracks that originate in the grease fitting holes on the side of the hub, which could result in propeller blade separation and loss of the aircraft, accomplish the following: 
	(a) For propellers installed on Textron Lycoming TIO-540 or LTIO-540 series reciprocating engines or turbocharged IO-540 series reciprocating engines which are installed on Piper PA-31-325 Navajo C/R, PA-31-350 Navajo "Chieftain," T-1020 (same as PA-31-350), PA-60-700P, Aerostar 700P aircraft, or propellers installed on any agricultural aircraft with any engine, accomplish the following: 
		(1) Within 10 hours time in service (TIS) after the effective date of this AD, but not to exceed 25 hours TIS since the last inspection, whichever occurs first, and thereafter at intervals of 10 hours TIS, perform a visual inspection for presence of grease on the propeller and determine the source of this grease leakage prior to further flight. Following the visual inspection, perform an eddy current inspection (ECI) or fluorescent penetrant inspection (FPI) for cracks in accordance with Hartzell Propeller, Inc. SB No. 165E, dated January 21, 1994. 

	NOTE: Use of a black light to inspect the suspect area can aid in determining the source of grease leakage because authorized grease contains fluorescent properties. 

			(i) If grease is leaking from the hub arm or wall, replace the propeller with a serviceable propeller prior to further flight. 
			(ii) If grease is determined to be leaking from other causes, take the appropriate corrective maintenance action and record in appropriate maintenance records. 
		(2) If a crack is found in a propeller hub during the inspections required in paragraph (a)(1) of this AD, replace the propeller hub prior to further flight with a new post-1983 configuration propeller hub, or with a serviceable 1983 or earlier hub that has been inspected in accordance with Hartzell Propeller Inc. SB No. 165E, dated January 21, 1994. Thereafter, perform a visual inspection, and ECI or FPI, for cracks in accordance with Hartzell Propeller Inc. SB No. 165E, dated January 21, 1994, at intervals not to exceed 10 hours TIS since the last inspection, unless a new post-1983 later style propeller hub is installed, per paragraph (d) of this AD. 
	(b) For propellers installed on all other aircraft models, except for the four non-agricultural models listed in paragraph (a) of this AD, and that utilize Textron Lycoming TIO-540, LTIO-540, or turbocharged IO-540 series reciprocating engines accomplish the following: 
		(1) Within 50 hours TIS after the effective date of this AD, but not to exceed 50 hours TIS since the last inspection, and thereafter at intervals of 50 hours TIS, perform a visual inspection for presence of grease on the propeller and determine the source of this grease leakage prior to further flight. Following the visual inspection, perform an ECI or FPI for cracks in accordance with Hartzell Propeller Inc. SB No. 165E, dated January 21, 1994. 

	NOTE: Use of a black light to inspect the suspect area can aid in determining the source of grease leakage because authorized grease contains fluorescent properties. 

			(i) If grease is leaking from the hub arm or wall, replace the propeller with a serviceable propeller prior to further flight. 
			(ii) If grease is determined to be leaking from other causes, take the appropriate corrective maintenance action and record in appropriate maintenance records. 
		(2) If a crack is found in a propeller hub during the inspections required in paragraph (b)(1) of this AD, replace the hub prior to further flight with a new post-1983 configuration propeller hub, or with a serviceable 1983 or earlier hub that has been inspected in accordance with Hartzell Propeller Inc. SB No. 165E, dated January 21, 1994. Thereafter, perform a visual inspection, and ECI or FPI, at intervals not to exceed 50 hours TIS since the last inspection, in accordance with paragraph (b)(1) of this AD, unless a new post-1983 configuration propeller hub is installed, per paragraph (d) of this AD. 
	(c) An alternative method of compliance in Hartzell Propeller Inc. SB No. 165E, dated January 21, 1994, describes a propeller hub modification to chamfer the inside and outside hub arm surfaces of the grease hole fitting. Performing this interim modification allows an operator to extend the initial and repetitive inspection period as required by paragraphs (a)(1) or (b)(1) of this AD, as applicable, to 400 hours TIS. 
		(1) For propellers installed on aircraft listed in paragraph (a) of this AD, once 400 hours TIS is reached, or 36 calendar months after the effective date of this AD, whichever occurs first, the propeller hub must be replaced in accordance with paragraph (d) of this AD. 
		(2) For propellers installed on aircraft listed in paragraph (b) of this AD, once 400 hours TIS is reached, or 36 calendar months after the effective date of this AD, whichever occurs first, an internal inspection is required at intervals not to exceed 400 hours TIS since last inspection in accordance with Hartzell Propeller Inc. SB No. 165E, dated January 21, 1994, or replacement of the hubs must be determined in accordance with paragraph (d) of this AD. 
	(d) For propellers installed on aircraft listed in paragraph (a) of this AD, install new post-1983 configuration propeller hubs that have fitting holes near the hub parting line prior to June 30, 1995, or in accordance with the time extension provided in paragraph (c) of this AD. For propellers installed in aircraft listed in paragraph (b) of this AD, this replacement is optional. For all affected propellers, this replacement constitutes terminating action to the inspection requirements of this AD. 
	(e) Propeller hubs that are configured 1983 or earlier, with the grease fitting holes located on the side of the hub, that have been removed from service cannot ever be approved for return to service. 
	(f) 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, Chicago 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, Chicago 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 Chicago Aircraft Certification Office. 

	(g) 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 inspections may be performed. 
	(h) The inspections and modification shall be done in accordance with the following service document: 

		Document No.		Pages		Date           
               
Hartzell Propeller Inc., SB No. 165E	1-10		Jan. 21, 1994.          
Total pages: 10             

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 Hartzell Propeller Inc., One Propeller Place, Piqua, OH 45356-2834; telephone (513) 778-4200, fax (513) 778-4391. 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. 
	(i) This amendment becomes effective on September 15, 1994. 

	Issued in Burlington, Massachusetts, on August 15, 1994. 

Jay J. Pardee, Manager, Engine and Propeller Directorate, Aircraft Certification Service. 

FOR FURTHER INFORMATION CONTACT: Tim Smyth, Aerospace Engineer, Chicago Aircraft Certification Office, FAA, Small Airplane Directorate, 2300 East Devon Avenue, Room 232, Des Plaines, IL 60018; telephone (708) 294-7130, fax (708) 294-7834.