Airworthiness Directives; Hoffmann Propeller Co. HO27( ) and HO4/27 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 Hoffmann Propeller Co. HO27( ) and HO4/27 series propellers. This action requires installing improved propeller mounting bolts to a higher torque value, operating the airplane for one flight, checking the torque, and retorquing, as required, to the correct torque value. This amendment is prompted by reports of insufficient torque of propeller mounting bolts due to operating conditions, loads, and environmental conditions such as humidity and temperature. The actions specified in this AD are intended to prevent propeller mounting bolt failure, which could result in propeller separation and loss of control of the airplane.

DATES:

Effective March 9, 2000.

Comments for inclusion in the Rules Docket must be received on or before April 24, 2000.

ADDRESSES:

Submit comments to the Federal Aviation Administration (FAA), New England Region, Office of the Regional Counsel, Attention: Rules Docket No. 98-ANE-64-AD, 12 New England Executive Park, Burlington, MA 01803-5299. Comments may also be sent via the Internet using the following address: “9-ane-adcomment@faa.gov”. Comments sent via the Internet must contain the docket number in the subject line.

FOR FURTHER INFORMATION CONTACT:

Frank Walsh, Aerospace Engineer, Boston Aircraft Certification Office, FAA, Engine and Propeller Directorate, 12 New England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-7158, fax (781) 238-7199.

SUPPLEMENTARY INFORMATION:

The Luftfahrt-Budesamt (LBA), which is the airworthiness authority for Germany, notified the Federal Aviation Administration (FAA) that an unsafe condition may exist on Hoffmann Propeller Co. HO27( ) and HO4/27 series propellers. The LBA advises that they have received reports of insufficient torque of propeller mounting bolts due to poor maintenance and operating conditions, loads, and environmental conditions such as humidity and temperature. This condition, if not corrected, could result in propeller mounting bolt failure, which could result in propeller separation and loss of control of the airplane.

Bilateral Airworthiness Agreement

This propeller model is manufactured in Germany and is type certificated for operation in the United States under the provisions of section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the LBA has kept the FAA informed of the situation described above. The FAA has examined the findings of the LBA, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Required Actions

Since an unsafe condition has been identified that is likely to exist or develop on other propellers of the same type design registered in the United States, the proposed AD would require installing improved propeller mounting bolts to the correct torque value. This AD would require the installation within 10 hours time-in-service, or 7 days after the effective date of this AD, whichever occurs first. After operating the airplane for one flight, check the torque, and retorque to the correct torque value, as required. The LBA classified this action as mandatory and issued airworthiness directive (AD) 1998-322/2, dated August 6, 1998, in order to assure the airworthiness of these propellers in Germany.

Immediate Adoption

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 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 98-ANE-64-AD.” The postcard will be date stamped and returned to the commenter.

Regulatory Impact

The regulations adopted herein will not have a substantial direct effect 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, it is determined that this final rule does not have federalism implications under Executive Order (EO) No. 13132.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in airplane, and is not a “significant regulatory action” under Executive Order No. 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
• 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. 106(g), 40113, 44701.

2. Section 39.13 is amended by adding the following new airworthiness directive:

2000-04-10 Hoffmann Propeller Co.: Amendment 39-11592. Docket 98-ANE-64-AD.

Applicability: Hoffmann Propeller Co. HO27( ) and HO4/27 series propellers, with propeller mounting bolts, part number (P/N) FP20-147 ( ) ( ) ( ), installed. These propellers are installed on but not limited to Textron Lycoming O-360 series and O-540 series, and Teledyne Continental Motors O-470 series reciprocating engine powered airplanes manufactured by Aeronca, Bellanca, Cessna, DeHavilland, Piper, Socata, Rallye, Stinson, and Varga.

Note 1:

The parentheses that appear in the propeller models indicate the presence or absence of additional letter(s) which vary the basic propeller hub model designation. This airworthiness directive (AD) is applicable regardless of whether these letters are present or absent on the propeller hub model designation.

Note 2:

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 request approval for an alternative method of compliance in accordance with paragraph (b) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent propeller mounting bolt failure, which could result in propeller separation and loss of control of the airplane, accomplish the following:

Improved Propeller Mounting Bolts

(a) Within 10 hours time-in-service (TIS), or 7 days after the effective date of this AD, whichever occurs first, remove from service propeller mounting bolts, P/N FP20-147

( )( )( ), and install improved propeller mounting bolts, P/N FP20-147 ( )( )( )V. Make sure the new bolts have the “V” marking at the end of the P/N.

Correct Torque

(b) Torque all six propeller mounting bolts to 24.3 to 25.8 foot-pounds or 33 to 35 Newton-meters.

Note 3:

Further information on propeller mounting bolt installation and torquing procedures can be found in Hoffmann Propeller Company Owner Manuals E0110.74 or 0207.71, and on the sticker on the propeller.

Retorque After First Flight

(c) After installation of new mounting bolts, operate the airplane for no more than 2 hours TIS, check torque and retorque, as required, to 24.3 to 25.8 foot-pounds or 33 to 35 Newton-meters.

Alternative Method of Compliance

(d) 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. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Boston Aircraft Certification Office.

Note 4:

Information concerning the existence of approved alternative methods of compliance with this airworthiness directive, if any, may be obtained from the Boston Aircraft Certification Office.

(e) This amendment becomes effective on March 9, 2000.