[Federal Register Volume 59, Number 29 (Friday, February 11, 1994)] [Unknown Section] [Page 0] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 94-3102] [[Page Unknown]] [Federal Register: February 11, 1994] ----------------------------------------------------------------------- DEPARTMENT OF TRANSPORTATION 14 CFR Part 39 [Docket No. 94-ANE-06; Amendment 39-8818; AD 94-03-11] Airworthiness Directives; Hartzell Propeller Inc. HC-B4 Series Propellers AGENCY: Federal Aviation Administration, DOT. ACTION: Final rule, request for comments. ----------------------------------------------------------------------- SUMMARY: This amendment adopts a new airworthiness directive (AD) that is applicable to Hartzell Propeller Inc. HC-B4 series propellers. This action requires a one-time inspection for fatigue cracks and rework of certain HC-B4 series propeller hub arm assemblies. This amendment is prompted by two aircraft accidents involving aircraft with HC-B4 series propellers and a determination that approximately 290 propeller hub arm assemblies that may have been exposed to operating characteristics similar to accident aircraft have not been inspected in accordance with two previous AD's, 93-09-04 and 93-12-01. The actions specified in this AD are intended to prevent fatigue cracks in propeller hub arm assemblies progressing to failure, resulting in departure of the hub arm and blade, and may result in engine separation and subsequent loss of aircraft control. DATES: Effective February 28, 1994. The incorporation by reference of certain publications listed in the regulations is approved by the Director of the Federal Register as of February 28, 1994. Comments for inclusion in the Rules Docket must be received on or before April 12, 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-06, 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 45356-2634; telephone (513) 778-4200. 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. 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 April 28, 1993, the Federal Aviation Administration (FAA) issued priority letter airworthiness directive (AD) 93-09-04, applicable to Hartzell Propeller Inc. HC-B4 series propellers installed on Mitsubishi Model MU-2B-60 aircraft, and published this AD in the Federal Register on July 22, 1993 (58 FR 39139). That AD was prompted by two reports of propeller hub arm assembly fatigue failure and subsequent propeller blade separation from aircraft in flight. Preliminary data indicated that fatigue cracks can originate in the propeller hub arm assembly. That AD requires removal from service of propeller hub assemblies, and replacement with serviceable propeller hub assemblies, on Mitsubishi Model MU-2B-60 aircraft. That condition, if not corrected, can result in fatigue cracks in propeller hub arm assemblies progressing to failure, resulting in departure of the hub arm and blade, and may result in engine separation and subsequent loss of aircraft control. Since the issuance of that AD, the FAA has received a report of a hub arm assembly with a crack indication in the hub arm that was found during the inspection and rework required by AD 93-09-04. The FAA determined it was necessary to issue a new priority letter AD 93-12-01 on June 10, 1993, and subsequently published this AD in the Federal Register on September 29, 1993 (58 FR 50840). That AD requires similar inspections and rework on these same propeller models installed on Mitsubishi MU-2B-26A, -36A, and -40 aircraft, as these aircraft have similar operating characteristics to the Mitsubishi Model MU-2B-60 aircraft, but have different performance limitations. Since the propeller installations on the Mitsubishi MU-2B series aircraft are operated at a higher propeller inflow angle during cruise than other aircraft with this same model propeller installed, it was necessary to inspect these additional MU-2B series aircraft as soon as possible. The FAA has determined by subsequent investigation that approximately 290 Hartzell Propeller Inc. HC-B4 series propeller hub arm assemblies, that at one time may have been installed on Mitsubishi MU-2B series aircraft, have not been inspected in accordance with either AD 93-09-04 or AD 93-12-01. These propeller hub arm assemblies may be exchanged and installed on several different aircraft models, and therefore it is possible that certain propeller hub arm assemblies outside the assemblies inspected and reworked in accordance with AD 93- 09-04 and AD 93-12-01 may have been previously installed on a Mitsubishi MU-2B series aircraft, but are now installed on other aircraft models. Since these propeller hub arm assemblies may have at one time been exposed to the operating characteristics of Mitsubishi MU-2B series aircraft, the FAA has determined there is a need to inspect these additional hub arm assemblies for fatigue cracking. Although the FAA and Hartzell Propeller Inc. have conducted a search for HC-B4 series propeller hub arm assemblies that have been previously installed on Mitsubishi MU-2B series aircraft but that are now installed on other aircraft models, the list of hub arm assembly serial numbers included in Hartzell Propeller Inc. ASB No. A186, dated January 25, 1994, cannot be viewed as exhaustive. This AD requires, therefore, that owners and operators of aircraft other than the Mitsubishi MU-2B series aircraft that have Hartzell Propeller Inc. HC- B4 series propellers installed determine whether their current Hartzell Propeller Inc. HC-B4 series propeller hub arm assemblies have seen previous service on Mitsubishi MU-2B series aircraft using methods such as a records check of aircraft or propeller maintenance records. The FAA has determined, however, that if an owner cannot determine from a records check if a HC-B4 propeller hub arm assembly now installed on another aircraft model ever saw service in a Mitsubishi MU-2B series aircraft and that propeller hub arm assembly is not listed in Hartzell Propeller Inc. ASB No. A186, dated January 25, 1994, the risk of that propeller hub arm assembly having seen service on a Mitsubishi MU-2B series aircraft is sufficiently low to warrant no further action. If the owner or operator determines that the currently installed Hartzell Propeller Inc. HC-B4 series steel propeller hub arm assembly has seen previous service on Mitsubishi MU-2B series aircraft, then it must be inspected for fatigue cracks and reworked. The FAA has reviewed and approved the technical contents of Hartzell Propeller Inc. Alert Service Bulletin (ASB) No. A186, dated January 25, 1994, that describes procedures for identifying, inspecting and reworking the affected propeller hub arm assemblies. Since an unsafe condition has been identified that is likely to exist or develop on other Hartzell Propeller Inc. HC-B4 series propellers of the same type design, this AD is being issued to require inspection for fatigue cracks and rework of certain Hartzell Propeller Inc. HC-B4 series propeller hub arm assemblies to prevent failure. The actions are required to be accomplished in accordance with the alert 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-06.'' 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 14 CFR part 39 of the Federal Aviation Regulations 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 adding the following new airworthiness directive: 94-03-11 Hartzell Propeller Inc.: Amendment 39-8818. Docket 94-ANE- 06. Applicability: Hartzell Propeller Inc. HC-B4 series propellers, except those propellers installed on Mitsubishi MU-2B-26A, -36A, - 40, and -60 aircraft. The affected propellers are installed on but not limited to the following aircraft: Beech F90 King Air, A100 and A100A King Air, B100 King Air; Construcciones Aeronauticas, SA (CASA) C-212-CB, -CC, and -CF; Dehavilland Heron--Saunders conversion ST-27B; Dornier DO228-100, -101, -200, -201, -202, -212; Embraer EMB-121A1 Xingu; Fairchild SA226-TB Merlin IIIB; Let L-410A; and Shorts SC-7 series 3, variant 200. NOTE: This airworthiness directive (AD) does not contain an exhaustive list of aircraft which utilize these propellers. Other Type Certificated models may not be included in the list, and other aircraft may use the affected propeller models through, for example, installation approvals made by Supplemental Type Certificate or FAA Form 337 ``Major Repair and Alteration.'' It is the responsibility of the owner, operator, or person returning the aircraft to service to determine if an aircraft has an affected propeller. Compliance: Required as indicated, unless accomplished previously. To prevent possible fatigue cracks in propeller hub arm assemblies progressing to failure, resulting in departure of the hub arm and blade, that may result in engine separation and subsequent loss of aircraft control, accomplish the following: (a) For each Hartzell Propeller Inc. HC-B4 series propeller currently installed on an aircraft other than Mitsubishi MU-2B series aircraft, determine if the propeller hub arm assembly has ever seen service on a Mitsubishi MU-2B series aircraft prior to performing the inspections required by the compliance schedule contained in paragraph (b) of this AD: (1) Determine if the currently installed propeller hub assembly matches a serial number (S/N) in Table 1 of Hartzell Propeller Inc. Alert Service Bulletin (ASB) No. A186, dated January 25, 1994; and (2) If the currently installed propeller hub assembly's S/N is not listed in Table 1 of Hartzell Propeller Inc. ASB No. A186, dated January 25, 1994, and an aircraft and propeller maintenance record search confirms the currently installed propeller hub assembly has not been previously installed on a Mitsubishi MU-2B series aircraft, or the service history cannot be determined, no further action is required. (3) If the record search reveals that the S/N of the currently installed propeller hub arm assembly is listed in Table 1 of Hartzell Propeller Inc. ASB No. A186, dated January 25, 1994, or the propeller hub arm assembly was installed previously on a Mitsubishi MU-2B series aircraft, remove the propeller hub arm assembly in accordance with the compliance schedule listed in paragraph (b) of this AD, and inspect and rework in accordance with the requirements of paragraph (c) of this AD. (b) For propeller hub arm assemblies identified in paragraph (a)(3) of this AD, remove from service in accordance with the following schedule: ------------------------------------------------------------------------ Time in service since new on the effective date of this AD (TSN) or assemblies that have experienced a Compliance required blade strike ------------------------------------------------------------------------ Greater than or equal to 3,000 Within the next 300 hours time in hours TSN. service (TIS), the next scheduled overhaul, or 24 calendar months after the effective date of this AD, whichever occurs first. Less than 3,000 hours TSN.......... Prior to the accumulation of 3,300 hours TSN, the next scheduled overhaul, or 24 calendar months after the effective date of this AD, whichever occurs first. Regardless of TSN, propeller hub Within the next 100 hours TIS, or 2 arm assemblies that have calendar months after the experienced a blade strike prior effective date of this AD, to the effective date of this AD. whichever occurs first. See paragraph (e) of this AD for the definition of blade strike. Regardless of TSN, propeller hub Prior to further flight. arm assemblies that experience a blade strike after the effective date of this AD. See paragraph (e) of this AD for the definition of a blade strike. ------------------------------------------------------------------------ (c) Remove affected propeller hub arm assemblies from the aircraft and return to Hartzell Service Center, 5465 West State Route 185, Piqua, OH 45356-2634 USA, telephone (513) 778-4205, for inspection and specified rework, in accordance with Hartzell Propeller Inc. ASB No. A186, dated January 25, 1994. (d) Reinstall serviceable propeller hub arm assemblies that had the hub arm bores inspected and reworked, as necessary, pilot tubes replaced, and were marked at the end of the hub arm assembly S/N with a suffix letter ``M'' in accordance with Hartzell Propeller Inc. ASB No. A186, dated January 25, 1994. (e) A blade strike is defined as a propeller having any blade or blades that have been bent beyond serviceable limits in accordance with Hartzell Propeller Inc. Service Letter (SL) 61S, dated December 10, 1993. (f) The ``calendar month'' compliance time stated in this AD allows the performance of the required action prior to the last day of the month in which compliance is required. Note: For example, if action is required 2 calendar months from April 28, 1994, the required actions are to be performed not later than June 30, 1994. (g) 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 Principal Maintenance Inspector, who may add comments and then send it to the Manager, Chicago Aircraft Certification Office. Note 1: 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. Note 2: Although Hartzell Service Center is presently the only FAA-approved repair facility authorized to conduct the requirements of this AD, other facilities may be authorized through the alternative method of compliance procedure in paragraph (g) of this AD. (h) Except when propeller hub arm assemblies experience a blade strike after the effective date of this AD, special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate the aircraft to a location where the requirements of this AD can be accomplished. (i) The removal, inspection, and rework shall be done in accordance with the following service documents: ------------------------------------------------------------------------ Document No. Pages Revision Date ------------------------------------------------------------------------ Hartzell ASB No. A186.............. 1-5 Original.... January 25, 1994. -------- Total pages...................... 5 ------------------------------------------------------------------------ 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 45356-2634. 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. (j) This amendment becomes effective on February 28, 1994. Issued in Burlington, Massachusetts, on February 2, 1994. Jay J. Pardee, Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 94-3102 Filed 2-10-94; 8:45 am] BILLING CODE 4910-13-P