Airworthiness Directives; Sensenich Propeller Manufacturing Company Inc. Models M76EMM, M7EMMS, 76EM8, and 76EM8S() Metal Propellers

[Federal Register Volume 60, Number 235 (Thursday, December 7, 1995)] [Proposed Rules] [Pages 62772-62774] From the Federal Register Online via the Government Publishing Office [www.gpo.gov] [FR Doc No: 95-29843]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 95-ANE-03]

Airworthiness Directives; Sensenich Propeller Manufacturing Company Inc. Models M76EMM, M7EMMS, 76EM8, and 76EM8S() Metal Propellers

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes to revise an existing airworthiness directive (AD), applicable to Sensenich Propeller Manufacturing Company Inc. Models M76EMM, M7EMMS, 76EM8, and 76EM8S() metal propellers, that currently restricts operators from continuously operating the propeller at engine speeds from 2,150 to 2,350 revolutions per minute (RPM). This action would remove propellers installed on certain additional Textron Lycoming O-360 series reciprocating engines with solid crankshafts from this requirement, and update the referenced Sensenich Propeller Company Inc. service bulletin to the latest revision. Reworking of all affected propeller models remains a requirement of the proposed AD, regardless of engine installation. This proposal is prompted by inquiries concerning tachometer red arc restrictions on certain Textron Lycoming O-360 series reciprocating engines with solid crankshafts. The actions specified by the proposed AD are intended to prevent propeller blade tip fatigue failure, which can result in loss of control of the aircraft.

DATES: Comments must be received by February 5, 1996.

ADDRESSES: 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-03, 12 New England Executive Park, Burlington, MA 01803-5299. Comments may be inspected at this location between 8:00 a.m. and 4:30 p.m., Monday through Friday, except Federal holidays. The service information referenced in the proposed rule may be obtained from Sensenich Propeller Manufacturing Company Inc., 519 Airport Road, Lititz, PA 17543; telephone (717) 569-0435, fax (717) 560-3725. This information may be examined at the FAA, New England Region, Office of the Assistant Chief Counsel, 12 New England Executive Park, Burlington, MA.

FOR FURTHER INFORMATION CONTACT: Raymond J. O'Neill, Aerospace Engineer, New York Aircraft Certification Office, FAA, Engine and Propeller Directorate, 10 Fifth St., Valley Stream, NY 11581; telephone (516) 256-7505, fax (516) 568-2716.

SUPPLEMENTARY INFORMATION:

Comments Invited

Interested persons are invited to participate in the making of the proposed 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 above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this notice may be changed in light of the comments received. Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed 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 summarizing each FAA-public contact concerned with the substance of this proposal 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-03.'' The postcard will be date stamped and returned to the commenter.

Availability of NPRMs

Any person may obtain a copy of this NPRM by submitting a request to the FAA, New England Region, Office of the Assistant Chief Counsel, Attention: Rules Docket No. 95-ANE-03, 12 New England Executive Park, Burlington, MA 01803-5299.

Discussion

On May 6, 1969, the Federal Aviation Administration (FAA) issued Airworthiness Directive (AD) 69-09-03, Amendment 39-761 (34 FR 7371, May 7, 1969), applicable to Sensenich Propeller Manufacturing Company Inc. Models M76EMM, M7EMMS, 76EM8, and 76EM8S() metal propellers. Revision 1, Amendment 39-808 (34 FR 12563, August 1, 1969); and Revision 2, Amendment 39-1102 (35 FR 17030, November 5, 1970), were subsequently

[[Page 62773]] issued. That AD restricts operators from continuously operating the propeller at engine speeds from 2,150 to 2,350 revolutions per minute (RPM) and requires reworking the propeller by reducing blade thickness and stiffness. That action was prompted by reports of propeller blade tip failures due to continuous operation in an RPM range of relatively high vibration stresses aggravated by impact-related mechanical damage such as cuts, nicks, and dents. That condition, if not corrected, could result in propeller blade tip fatigue failure, which can result in loss of control of the aircraft. Since the issuance of that AD, the FAA has received numerous inquiries from the field concerning tachometer red arc restrictions on certain Textron Lycoming O-360 series reciprocating engines with solid crankshafts that are identified by suffixes having a digit ``4'' or higher in the second position, e.g. A4AD, A4M, etc. The FAA has determined that these additional engines, with solid crankshafts, have vibration characteristics that closely approximate engines to which the current AD does not apply, and can therefore also be removed from the AD's applicability and requirement for tachometer restriction. Contrary to the requirements of AD 69-09-03 R2, this AD would require reworking all affected propellers, regardless of engine installation. When propeller blade reworking is accomplished, the resulting reduction in blade thickness and stiffness reduces blade second order- first mode peak resonance RPM to lower values. The reworked propeller (later adopted in production) is marked with the letter ``K.'' The FAA has reviewed and approved the technical contents of Sensenich Propeller Service Bulletin (SB) No. R-13, dated April 11, 1969, that describes avoiding continuous operation between 2150 and 2350 RPM; and Sensenich Propeller SB No. R-14A, dated November 15, 1994, that describes reworking the propeller by reducing blade thickness and stiffness in order to avoid propeller blade tip failures. Since an unsafe condition has been identified that is likely to exist or develop on other products of this same type design, the proposed AD would revise AD 69-09-03 R2 to remove from the AD's applicability propellers installed on certain Textron Lycoming O-360 series reciprocating engines with solid crankshafts that are identified by suffixes having a digit ``4'' or higher in the second position, e.g. A4A, A4G, etc., and from the tachometer restriction, and update the referenced Sensenich Propeller SB No. R-14 to R-14A, dated November 15, 1994. There are approximately 100 propellers of the affected design that may not have been modified to the ``K'' standard in the worldwide fleet. The FAA estimates that 50 propellers installed on aircraft of U.S. registry would be affected by this proposed AD, that it would take approximately 2.5 work hours per propeller to accomplish the proposed actions, and that the average labor rate is $60 per work hour. Based on these figures, the total cost impact of the proposed AD on U.S. operators is estimated to be $7,500. However, since this proposed rule further restricts the applicability by exempting propellers installed on certain Textron Lycoming engine models from the tachometer restriction, there is a potential overall cost savings of $4,395,000, if all the affected Sensenich propellers are installed on the newly exempted engines. The regulations proposed herein would 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 proposal would not have sufficient federalism implications to warrant the preparation of a Federalism Assessment. For the reasons discussed above, I certify that this proposed regulation (1) is not a ``significant regulatory action'' under Executive Order 12866; (2) is not a ``significant rule'' under the DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) if promulgated, will not have a significant economic impact, positive or negative, on a substantial number of small entities under the criteria of the Regulatory Flexibility Act. A copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend 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.

Sec. 39.13 [Amended]

2. Section 39.13 is amended by removing Amendment 39-1102 (35 FR 17030, November 5, 1970), and by adding a new airworthiness directive, to read as follows:

Sensenich Propeller Manufacturing Company Inc.: Docket No. 95-ANE- 03. Revises AD 69-09-03, Amendment 39-1102.

Applicability: Sensenich Propeller Manufacturing Company Inc. Models M76EMM, M7EMMS, 76EM8, and 76EM8S() metal propellers. Paragraphs (a) and (b) of this airworthiness directive (AD) do not apply to those propellers installed on the following solid crankshaft Textron Lycoming O-360 series reciprocating engines: O- 360-A4A, -A4D, -A4G, -A4J, -A4K, -A4M, -A4N, -A4P, and -A5AD, or additional engines identified by suffixes having a digit ``4'' or higher in the second position. These propellers are installed on but not limited to the following aircraft: Piper PA-28-180, PA-28-181, American General Aircraft Holding Co. Inc. (formerly Gulfstream American) AA-5 series, Beech B23 and C23, Cessna 172Q, Avions Pierre Robin R-3000/160, and aircraft modified under various Supplemental Type Certificates (STC's).

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 (f) 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 propeller blade tip fatigue failure, which can result in loss of control of the aircraft, accomplish the following: (a) Commencing with the next flight after the effective date of this AD, do not operate the engine in continuous operation between 2,150 and 2,350 RPM. (b) Within the next 25 hours time in service (TIS) after the effective date of this AD, mark engine tachometer with a red arc from 2150 RPM to 2350 RPM, in accordance with Sensenich Propeller Service Bulletin (SB) No. R-13, dated April 11, 1969.

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(c) For propellers with 500 or more total hours TIS, or unknown TIS on the effective date of this AD, inspect, and rework or replace, as necessary, within the next 50 hours TIS after the effective date of this AD, in accordance with Sensenich Propeller SB No. R-14A, dated November 15, 1994. (d) For propellers with less than 500 total hours TIS on the effective date of this AD, inspect, and rework or replace, as necessary, prior to accumulating 550 total hours TIS, in accordance with Sensenich Propeller SB No. R-14A, dated November 15, 1994. (e) Mark with a suffix letter ``K'' propellers that have been inspected, reworked, or replaced in accordance with Sensenich Propeller SB No. R-14A, dated November 15, 1994, and found satisfactory. New production propellers include change ``K'' or subsequent changes. (f) An alternative method of compliance or adjustment of the initial compliance time that provides an acceptable level of safety may be used if approved by the Manager, New York 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, New York Aircraft Certification Office.

Note: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York 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 requirements of this AD can be accomplished.

Issued in Burlington, Massachusetts, on November 28, 1995. Jay J. Pardee, Manager, Engine and Propeller Directorate, Aircraft Certification Service. [FR Doc. 95-29843 Filed 12-6-95; 8:45 am] BILLING CODE 4910-13-P