AD 2000-04-10

final rule

Airworthiness Directives; Hoffmann Propeller Co. HO27( ) and HO4/27 Series Propellers

AD Number
2000-04-10
Status
final_rule
Effective Date
Product Category
propeller
Docket
Docket No. 98-ANE-64-AD
FR Citation
65 FR 8844
Technical illustration of an aircraft propeller assembly
Problem area Propeller

Applicability

TypeManufacturerModelDetails
aircraft Hoffmann GmbH & Co. KG HO 27 HM Airworthiness Directives; Hoffmann Propeller Co. HO27( ) and HO4/27 Series Propellers
aircraft Hoffmann GmbH & Co. KG HO 4/27 ( ) Airworthiness Directives; Hoffmann Propeller Co. HO27( ) and HO4/27 Series Propellers
aircraft Hoffmann GmbH & Co. KG HO 4/27 ( ) HM Airworthiness Directives; Hoffmann Propeller Co. HO27( ) and HO4/27 Series Propellers
propeller Hoffmann GmbH & Co. KG HO 27 HM Airworthiness Directives; Hoffmann Propeller Co. HO27( ) and HO4/27 Series Propellers
propeller Hoffmann GmbH & Co. KG HO 4/27 ( ) Airworthiness Directives; Hoffmann Propeller Co. HO27( ) and HO4/27 Series Propellers
propeller Hoffmann GmbH & Co. KG HO 4/27 ( ) HM Airworthiness Directives; Hoffmann Propeller Co. HO27( ) and HO4/27 Series Propellers

Unsafe Condition

Insufficient torque of propeller mounting bolts due to operating conditions, loads, and environmental conditions such as humidity and temperature, which could lead to propeller mounting bolt failure and subsequent propeller separation.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Install improved propeller mounting bolts to a higher torque value, operate the airplane for one flight, check the torque, and retorque as required to the correct torque value.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Before further flight.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Hoffmann Propeller Co. HO27( ) and HO4/27 series propellers.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

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.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 65, Number 36 (Wednesday, February 23, 2000)]
[Rules and Regulations]
[Pages 8844-8845]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 00-4262]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-ANE-64-AD; Amendment 39-11592; AD 2000-04-10]
RIN 2120-AA64


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: ``<a href="/cdn-cgi/l/email-protection#efd6c28e818ac28e8b8c8082828a819baf898e8ec1888099"><span class="__cf_email__" data-cfemail="d1e8fcb0bfb4fcb0b5b2bebcbcb4bfa591b7b0b0ffb6bea7">[email&#160;protected]</span></a>''. 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

[[Page 8845]]

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.


Sec. 39.13  [Amended]

    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.

    Issued in Burlington, Massachusetts, on February 14, 2000.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 00-4262 Filed 2-22-00; 8:45 am]
BILLING CODE 4910-13-U

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Retrieved: Apr 6, 2026

Rights: U.S. Government Public Domain

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