Document ID: FAA-2020-1104-0001
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Hoffmann GmbH and Co. KG Propellers
Posted Date: 2020-12-07T05:00Z

[Federal Register Volume 85, Number 235 (Monday, December 7, 2020)]
[Rules and Regulations]
[Pages 78702-78705]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-26765]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-1104; Project Identifier MCAI-2020-01421-P; 
Amendment 39-21347; AD 2020-25-05]
RIN 2120-AA64

Airworthiness Directives; Hoffmann GmbH & Co. KG Propellers

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule; request for comments.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all 
Hoffmann GmbH & Co. KG (Hoffmann) model HO-V 72 propellers. This AD was 
prompted by reports of cracks at different positions on two affected 
propeller hubs. This AD requires amending the existing aircraft flight 
manual (AFM) with abnormal propeller vibration instructions. This AD 
requires visual inspection and non-destructive test (NDT) inspection of 
the propeller hub and, depending on the results of the inspections, 
replacement of the propeller hub with a part eligible for installation. 
This AD also requires replacement of the propeller hub before exceeding 
30 years since the date of manufacture or within 30 days after the 
effective date of this AD, whichever occurs later. The FAA is issuing 
this AD to address the unsafe condition on these products.

DATES: This AD is effective December 22, 2020.
    The Director of the Federal Register approved the incorporation by 
reference of a certain publication listed in this AD as of December 22, 
2020.
    The FAA must receive comments on this AD by January 21, 2021.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this final rule, contact 
Hoffmann Propeller GmbH & Co. KG, Sales and Service, 
K[uuml]pferlingstrasse 9, 83022, Rosenheim, Germany; phone: +49 (0) 
exception occurred on : 2020-26765.htm
exception occurred on : 2020-26765.htm
8031 1878 0; fax: +49 (0) 8031 1878 78; email: prop.com">[email protected]prop.com; 
website: https://hoffmann-prop.com/. You may view this service 
information at the FAA, Airworthiness Products Section, Operational 
Safety Branch, 1200 District Avenue, Burlington, MA 01803. For 
information on the availability of this material at the FAA, call (781) 
238-7759. It is also available at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2020-1104.

Examining the AD Docket

    You may examine the AD docket at https://www.regulations.gov by 
searching for and locating Docket No. FAA-2020-1104; or in person at 
Docket Operations between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The AD docket contains this final rule, any 
comments received, and other information. The street address for the 
Docket Operations is listed above.

FOR FURTHER INFORMATION CONTACT: Michael Schwetz, Aviation Safety 
Engineer, Boston ACO Branch, FAA, 1200 District Avenue, Burlington, MA 
01803; phone: (781) 238-7761; fax: (781) 238-7199; email: 
michael.schwetz@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

    The European Union Aviation Safety Agency (EASA), which is the 
Technical Agent for the Member States of the European Community, has 
issued EASA AD 2020-0226-E, dated October 16, 2020 (referred to after 
this as ``the MCAI''), to address an unsafe condition for the specified 
products. The MCAI states:

    Cracks have been reported at different positions on two affected 
parts, both installed on Slingsby T67 ``Firefly'' aeroplanes. One 
crack was found during scheduled inspection, the other crack during 
an unscheduled inspection after abnormal vibrations occurred. Both 
cases are under investigation by Hoffmann Propeller.
    This condition, if not detected and corrected, could lead to in-
flight propeller detachment, possibly resulting in damage to the 
airplane and/or injury to persons on the ground.
    To address this potential unsafe condition, Hoffmann issued the 
SB [service bulletin], providing applicable instructions.
    For the reasons described above, this [EASA] AD requires 
inspections of affected parts and, depending on findings, 
replacement, and introduces a life limit for affected parts. This 
[EASA] AD also requires, for certain aeroplanes, amendment of the 
applicable Aircraft Flight Manual (AFM).

    You may obtain further information by examining the MCAI in the AD 
docket at https://www.regulations.gov by searching for and locating 
Docket No. FAA-2020-1104.

FAA's Determination

    The FAA is issuing this AD because the agency has determined the 
unsafe condition described previously is likely to exist or develop in 
other products of the same type design.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Hoffmann Propeller GmbH & Co. KG Service Bulletin 
SB E53, Rev. B, dated October 14, 2020. This service information 
specifies procedures for visual and NDT inspections of the propeller 
hub for cracks. This service information is reasonably available 
because the interested parties have access to it through their normal 
course of business or by the means identified in ADDRESSES.

AD Requirements

    This AD requires amending the existing AFM with abnormal propeller 
vibration instructions. This AD also requires visual inspection and NDT 
inspection of the propeller hub and, depending on the results of the 
inspections, replacement of the propeller hub with a part eligible for 
installation. This AD also requires replacement of the propeller hub 
before exceeding 30 years since the date of manufacture or within 30 
days after the effective date of this AD, whichever occurs later.

Differences Between the AD and the MCAI

    EASA AD 2020-0226-E, dated October 16, 2020, applies to Hoffmann 
HO-V 72 propellers with propeller hub HO-V 72 ( ) ( )-( )-( ) that have 
been used or are expected to be used for aerobatic maneuvers. This AD 
applies to all Hoffmann model HO-V 72 propellers regardless of their 
use.

[[Page 78703]]

    EASA AD 2020-0226-E, dated October 16, 2020, defines the life of 
the propeller hub as 30 years since the first installation on the 
airplane. This AD defines the life of the propeller hub as 30 years 
since the date of manufacture because the installation history of the 
propeller might be unknown.

Interim Action

    The FAA considers this AD interim action. This unsafe condition is 
still under investigation by the manufacturer and, depending on the 
results of that investigation, the FAA may consider further rulemaking 
action.

Justification for Immediate Adoption and Determination of the Effective 
Date

    Section 553(b)(3)(B) of the Administrative Procedure Act (APA) (5 
U.S.C. 551 et seq.) authorizes agencies to dispense with notice and 
comment procedures for rules when the agency, for ``good cause,'' finds 
that those procedures are ``impracticable, unnecessary, or contrary to 
the public interest.'' Under this section, an agency, upon finding good 
cause, may issue a final rule without providing notice and seeking 
comment prior to issuance. Further, section 553(d) of the APA 
authorizes agencies to make rules effective in less than thirty days, 
upon a finding of good cause.
    An unsafe condition exists that requires the immediate adoption of 
this AD without providing an opportunity for public comments prior to 
adoption. The FAA has found that the risk to the flying public 
justifies foregoing notice and comment prior to adoption of this rule. 
During a scheduled inspection, a crack was found by an operator on a 
propeller hub. A second crack was found on another propeller hub during 
an unscheduled inspection by an operator after abnormal vibrations 
occurred in-flight. Hoffmann Propeller immediately issued service 
information instructing operators to visually inspect the hub for 
cracks before the next flight while the cause of the cracks are under 
investigation.
    A crack in the propeller hub can result in the loss of a propeller 
blade, resulting in an imbalance in the entire engine which can render 
the aircraft uncontrollable. The FAA considers a crack in the propeller 
hub an urgent safety issue that requires an immediate action to avoid 
potential loss of the airplane. Accordingly, notice and opportunity for 
prior public comment are impracticable and contrary to the public 
interest pursuant to 5 U.S.C. 553(b)(3)(B). In addition, the FAA finds 
that good cause exists pursuant to 5 U.S.C. 553(d) for making this 
amendment effective in less than 30 days, for the same reasons the FAA 
found good cause to forego notice and comment.

Comments Invited

    The FAA invites you to send any written data, views, or arguments 
about this final rule. Send your comments to an address listed under 
ADDRESSES. Include the docket number FAA-2020-1104 and Project 
Identifier MCAI-2020-01421-P at the beginning of your comments. The 
most helpful comments reference a specific portion of the final rule, 
explain the reason for any recommended change, and include supporting 
data. The FAA will consider all comments received by the closing date 
and may amend this final rule because of those comments.
    Except for Confidential Business Information (CBI) as described in 
the following paragraph, and other information as described in 14 CFR 
11.35, the FAA will post all comments received, without change, to 
https://www.regulations.gov, including any personal information you 
provide. The agency will also post a report summarizing each 
substantive verbal contact received about this final rule.

Confidential Business Information

    CBI is commercial or financial information that is both customarily 
and actually treated as private by its owner. Under the Freedom of 
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public 
disclosure. If your comments responsive to this AD contain commercial 
or financial information that is customarily treated as private, that 
you actually treat as private, and that is relevant or responsive to 
this AD, it is important that you clearly designate the submitted 
comments as CBI. Please mark each page of your submission containing 
CBI as ``PROPIN.'' The FAA will treat such marked submissions as 
confidential under the FOIA, and they will not be placed in the public 
docket of this AD. Submissions containing CBI should be sent to Michael 
Schwetz, Aviation Safety Engineer, Boston ACO Branch, FAA, 1200 
District Avenue, Burlington, MA 01803. Any commentary that the FAA 
receives which is not specifically designated as CBI will be placed in 
the public docket for this rulemaking.

Regulatory Flexibility Act

    The requirements of the Regulatory Flexibility Act (RFA) do not 
apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt 
a rule without prior notice and comment. Because FAA has determined 
that it has good cause to adopt this rule without prior notice and 
comment, RFA analysis is not required.

Costs of Compliance

    The FAA estimates that this AD affects 35 propellers installed on 
airplanes of U.S. registry.
    The FAA estimates the following costs to comply with this AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
               Action                         Labor cost            Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Amend AFM..........................  1 work-hour x $85 per hour               $0             $85          $2,975
                                      = $85.
Visually inspect propeller hub.....  1 work-hour x $85 per hour                0              85           2,975
                                      = $85.
NDT inspect propeller hub..........  8 work-hours x $85 per hour               0             680          23,800
                                      = $680.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary 
replacement that would be required based on the results of the 
inspections. The agency has no way of determining the number of 
aircraft that might need this replacement:

[[Page 78704]]

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                    Action                                 Labor cost               Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replace propeller hub.........................  5 work-hours x $85 per hour =             $1,600          $2,025
                                                 $425.
----------------------------------------------------------------------------------------------------------------

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. ``Subtitle VII: Aviation Programs'' 
describes in more detail the scope of the Agency's authority.
    The FAA is issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701: General requirements. 
Under that section, Congress charges the FAA with promoting safe flight 
of civil aircraft in air commerce by prescribing regulations for 
practices, methods, and procedures the Administrator finds necessary 
for safety in air commerce. This regulation is within the scope of that 
authority because it addresses an unsafe condition that is likely to 
exist or develop on products identified in this rulemaking action.

Regulatory Findings

    This AD will not have federalism implications under Executive Order 
13132. This AD 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.
    For the reasons discussed above, I certify that this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866, and
    (2) Will not affect intrastate aviation in Alaska.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

2020-25-05 Hoffmann GmbH & Co. KG: Amendment 39-21347; Docket No. 
FAA-2020-1104; Project Identifier MCAI-2020-01421-P.

(a) Effective Date

    This airworthiness directive (AD) is effective December 22, 
2020.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to all Hoffmann GmbH & Co. KG (Hoffmann) model 
HO-V 72 propellers.

(d) Subject

    Joint Aircraft System Component (JASC) Code 6114, Propeller Hub 
Section.

(e) Unsafe Condition

    This AD was prompted by reports of cracks at different positions 
on two affected propeller hubs. The FAA is issuing this AD to 
prevent failure of the propeller hub. The unsafe condition, if not 
addressed, could result in release of the propeller, damage to the 
airplane, and injury to persons on the ground.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Required Actions

    (1) Before the next flight after the effective date of this AD, 
amend the existing aircraft flight manual by inserting the 
procedure: ``Abnormal propeller vibrations: As applicable, reduce 
engine RPM.''
    (2) Before the next flight after the effective date of this AD, 
and thereafter, before the next flight after any flight where 
abnormal propeller vibrations have been experienced, visually 
inspect propeller hub HO-V 72 ( ) ( )-( )-( ) for cracks using 
paragraph 2.1 of Hoffmann Propeller GmbH & Co. KG Service Bulletin 
SB E53, Rev. B, dated October 14, 2020 (the SB).
    (3) Within 20 flight hours after the effective date of this AD, 
perform a non-destructive test (NDT) inspection of propeller hub HO-
V 72 ( ) ( )-( )-( ) using paragraph 2.3 of the SB.
    (4) If, during any inspection required by paragraph (g)(2) or 
(3) of this AD, any crack is detected, replace propeller hub HO-V 72 
( ) ( )-( )-( ) with a part eligible for installation.
    (5) During each overhaul of propeller hub HO-V 72 ( ) ( )-( )-( 
) after the effective date of this AD, perform an NDT inspection 
using paragraph 2.3 of the SB.
    (6) Before exceeding 30 years since the date of manufacture, or 
within 30 days after the effective date of this AD, whichever occurs 
later, replace propeller hub HO-V 72 ( ) ( )-( )-( ) with a part 
eligible for installation.

(h) Definition

    For the purpose of this AD, a ``part eligible for installation'' 
is a propeller hub HO-V 72 ( ) ( )-( )-( ) with zero hours time 
since new or a propeller hub HO-V 72 ( ) ( )-( )-( ) that has 
accumulated fewer than 30 years since the date of manufacture and 
has passed an NDT inspection using paragraph 2.3 of the SB.

(i) Non-Required Actions

    (1) Sending the propeller to Hoffmann for investigation, as 
contained in paragraph 2.1 of the SB, is not required by this AD.
    (2) Reporting propeller hubs with cracks to Hoffmann, as 
contained in paragraph 2.3 of the SB, is not required by this AD.

(j) Credit for Previous Actions

    You may take credit for the initial visual inspection and NDT 
inspection of the propeller hub required by paragraphs (g)(2), (3), 
and (5) of this AD if you performed any of these actions before the 
effective date of this AD using Hoffmann Propeller GmbH & Co. KG SB 
E53 Rev. A, dated October 9, 2020.

(k) Special Flight Permit

    A special flight permit may be issued in accordance with 14 CFR 
21.197 and 21.199 to operate the airplane to a service facility to 
perform the NDT inspection. Special flight permits are prohibited to 
perform the visual inspection of the propeller hub.

(l) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Boston ACO Branch, FAA, has the authority to 
approve AMOCs for this AD, if requested using the procedures found 
in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request 
to your principal inspector or local Flight Standards District 
Office, as appropriate. If sending information directly to the 
manager of the certification office, send it to the attention of the 
person identified in Related Information.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(m) Related Information

    (1) For more information about this AD, contact Michael Schwetz, 
Aviation Safety Engineer, Boston ACO Branch, FAA, 1200 District 
Avenue, Burlington, MA 01803; phone: (781) 238-7761; fax: (781) 238-
7199; email: michael.schwetz@faa.gov.
    (2) Refer to European Union Aviation Safety Agency (EASA) AD 
2020-0226-E, dated October 16, 2020, for more

[[Page 78705]]

information. You may examine the EASA AD in the AD docket at https://www.regulations.gov by searching for and locating it in Docket No. 
FAA-2020-1104.

(n) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) Hoffmann Propeller GmbH & Co. KG (Hoffmann) Service Bulletin 
SB E53, Rev. B, dated October 14, 2020.
    (ii) [Reserved]
    (3) For Hoffmann service information identified in this AD, 
contact Hoffmann Propeller GmbH & Co. KG, Sales and Service, 
K[uuml]pferlingstrasse 9, 83022, Rosenheim, Germany; phone: +49 (0) 
exception occurred on : 2020-26765.htm
exception occurred on : 2020-26765.htm
8031 1878 0; fax: +49 (0) 8031 1878 78; email: prop.com">[email protected]prop.com; website: https://hoffmann-prop.com/.
    (4) You may view this service information at FAA, Airworthiness 
Products Section, Operational Safety Branch, 1200 District Avenue, 
Burlington, MA 01803. For information on the availability of this 
material at the FAA, call (781) 238-7759.
    (5) You may view this service information that is incorporated 
by reference at the National Archives and Records Administration 
(NARA). For information on the availability of this material at 
NARA, email: fedreg.legal@nara.gov, or go to: https://www.archives.gov/federal-register/cfr/ibr-locations.html.

    Issued on November 30, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-26765 Filed 12-4-20; 8:45 am]
BILLING CODE 4910-13-P