
[Federal Register Volume 76, Number 74 (Monday, April 18, 2011)]
[Proposed Rules]
[Pages 21675-21677]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2011-9258]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-1270; Directorate Identifier 2001-NE-50-AD]

RIN 2120-AA64


Airworthiness Directives; Dowty Propellers Type R321/4-82-F/8, 
R324/4-82-F/9, R333/4-82-F/12, and R334/4-82-F/13 Propeller Assemblies

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to revise an existing airworthiness directive (AD) 
that applies to the products listed above. The existing AD currently 
requires initial and repetitive ultrasonic inspections of propeller 
hubs, part number (P/N) 660709201. Since we issued that AD, Dowty 
Propellers introduced a new hub assembly P/N. This proposed AD would 
revise that AD by introducing as an optional terminating action for the 
initial and repetitive ultrasonic inspections of that AD, replacement 
of propeller hub P/N 660709201 with a new propeller hub, P/N 660717226. 
We are proposing this AD to prevent that same propeller hub failure due 
to cracks in the hub, which could result in loss of control of the 
airplane, and to introduce an optional terminating action.

DATES: We must receive comments on this proposed AD by June 2, 2011.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://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 AD, contact Dowty 
Propellers, Anson Business Park, Cheltenham Road East, Gloucester GL 
29QN, UK; telephone: 44 (0) 1452 716000; fax: 44 (0) 1452 716001. You 
may review copies of the referenced service information at the FAA, 
Engine & Propeller Directorate, 12 New England Executive Park, 
Burlington, MA. For information on the availability of this material at 
the FAA, call 781-238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Office (phone: 800-647-5527) is in the ADDRESSES 
section. Comments will be available in the AD docket shortly after 
receipt.

FOR FURTHER INFORMATION CONTACT: Michael Schwetz, Aerospace Engineer, 
Boston Aircraft Certification Office, FAA, 12 New England Executive 
Park, Burlington, MA 01803; phone: 781-238-7761; fax: 781-238-7170; e-
mail: michael.schwetz@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2010-1270; 
Directorate Identifier 2001-NE-50-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    On December 2, 2005, we issued AD 2005-25-10, Amendment 39-14403 
(70 FR 73364, December 12, 2005), for Dowty Propellers type R321/4-82-
F/8, R324/4-82-F/9, R333/4-82-F/12, and R334/4-82-F/13 propeller 
assemblies. That AD requires initial and repetitive ultrasonic 
inspections of propeller hubs, P/N 660709201. That AD resulted from a 
report of a hub separation on a CASA 212 airplane, and mandatory 
continuing airworthiness information (MCAI) issued by an aviation 
authority of another country to identify and correct an unsafe 
condition on an aviation product. We issued that AD to prevent 
propeller hub failure due to cracks in the hub, which could result in 
loss of control of the airplane.

Actions Since Existing AD Was Issued

    Since we issued AD 2005-25-10, the European Aviation Safety Agency 
(EASA) has issued AD 2010-0196R1, dated November 12, 2010, which 
requires initial and repetitive ultrasonic inspections of propeller 
hubs, and introduces a new P/N propeller hub as optional terminating 
action to the inspections.

Relevant Service Information

    We have reviewed the technical contents of Dowty Propellers Alert 
Service Bulletin (SB) No. 61-1119, Revision 5, dated July 1, 2009, 
Alert SB No. 61-1124, Revision 2, dated August 25, 2010, Alert SB No. 
61-1125, Revision 2, dated August 25, 2010, and Alert SB No. 61-1126, 
Revision 2, dated August 25, 2010. The SBs describe procedures for 
initial and repetitive ultrasonic inspections of the rear wall of the 
rear half of the propeller hub for cracks on types R334/4-82-F/13, 
R333/4-82-F/12, R321/4-82-F/8, and R324/4-82-F/9 propeller assemblies, 
respectively. The SBs also introduce new hub assembly P/N 660717226, as 
optional terminating action for the initial and repetitive inspections. 
EASA

[[Page 21676]]

classified the service information as mandatory and issued AD 2010-
0196R1, dated November 12, 2010, to ensure the airworthiness of these 
propeller assemblies in Europe.

Bilateral Agreement Information

    These propeller assemblies are manufactured in the United Kingdom, 
and are 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. Under this 
bilateral airworthiness agreement, EASA kept us informed of the 
situation described above. We have examined the findings of the EASA, 
reviewed all available information, and determined that AD action is 
necessary for products of these type designs that are certificated for 
operation in the United States.

FAA's Determination

    We are proposing this AD revision because we evaluated all the 
relevant information and determined the unsafe condition described 
previously is likely to exist or develop in other products of these 
same type designs.

Proposed AD Requirements

    This proposed AD would retain the inspection requirements of AD 
2005-25-10. This proposed AD would introduce the installation of a new 
P/N hub assembly as optional terminating action to the inspections. 
This proposed AD would also eliminate the inspection reporting 
requirements, since we have already collected sufficient data.

Differences Between the Proposed AD and the Service Information or MCAI

    Although Appendix A of Alert SB No. 61-1119, Revision 5, dated July 
1, 2009, requires reporting the inspection data to Dowty Propellers, 
this proposed AD would not require any reporting.
    Although the MCAI uses initial inspection compliance times of 20 
days/60 days, we removed them from the proposed AD, since the unsafe 
condition is not related to corrosion.

Costs of Compliance

    We estimate that this proposed AD would affect 132 propellers 
installed on airplanes of U.S. registry. We also estimate that it would 
take about 0.5 work-hour per propeller to perform the proposed 
inspection and about 1 hour to replace a propeller hub. The average 
labor rate is $85 per work-hour. Required parts would cost about 
$19,500 per engine. Based on these figures, we estimate the total cost 
of the proposed AD to U.S. operators to be $2,590,830.

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.
    We are 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

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 the 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),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

List of Subjects in 14 CFR Part 39

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

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. The FAA amends Sec.  39.13 by removing airworthiness directive 
(AD) 2005-25-10, Amendment 39-14403 (70 FR 73364, December 12, 2005), 
and adding the following new AD:

Dowty Propellers (formerly Dowty Aerospace; Dowty Rotol Limited; and 
Dowty Rotol): Docket No. FAA-2010-1270; Directorate Identifier 2001-
NE-50-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by June 2, 
2011.

Affected ADs

    (b) This AD revises AD 2005-25-10, Amendment 39-14403.

Applicability

    (c) This AD applies to Dowty Propellers Type R321/4-82-F/8, 
R324/4-82-F/9, R333/4-82-F/12, and R334/4-82-F/13 propeller 
assemblies with propeller hubs part number (P/N) 660709201.

Unsafe Condition

    (d) This AD was prompted by the need to introduce an optional 
terminating action for the repetitive inspections. We are issuing 
this AD to prevent propeller hub failure due to cracks in the hub, 
which could result in loss of control of the airplane, and to 
introduce an optional terminating action.

Compliance

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

Initial Ultrasonic Inspections

    (f) Perform an initial ultrasonic inspection of the rear wall of 
the rear half of the propeller hub for cracks within the compliance 
time specified in Table 1 of this AD. Use Appendix A or Appendix D 
of the applicable Dowty Alert Service Bulletin (SB) listed in Table 
1 of this AD to do the inspection.

[[Page 21677]]



                                 Table 1--Applicable Alert SB for Propeller Type
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                                          Initial inspection       Repeat inspection
       Propeller assembly type                  within                   within               Applicable SB
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(1) R334/4-82-F/13...................  10 flight hours (FH)     300 FH time-since-last-  Alert SB No. 61-1119,
                                        time-in-service (TIS)    inspection (TSLI) or     Revision 5, dated July
                                        after the effective      300 flight cycles-       1, 2009.
                                        date of this AD.         since-last inspection,
                                                                 whichever occurs
                                                                 sooner.
(2) R321/4-82-F/8....................  50 FH TIS after the      1,000 FH TSLI..........  Alert SB No. 61-1125,
                                        effective date of this                            Revision 2, dated
                                        AD.                                               August 25, 2010.
(3) R324/4-82-F/9....................  50 FH TIS after the      1,000 FH TSLI..........  Alert SB No. 61-1126,
                                        effective date of this                            Revision 2, dated
                                        AD.                                               August 25, 2010.
(4) R333/4-82-F/12...................  50 FH TIS after the      1,000 FH TSLI..........  Alert SB No. 61-1124,
                                        effective date of this                            Revision 2, dated
                                        AD.                                               August 25, 2010.
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     (g) For hubs and propellers in storage, perform an initial 
ultrasonic inspection of the rear wall of the rear half of the 
propeller hub for cracks, before placing in service. Use Appendix A 
or Appendix D of the applicable Dowty Alert SB listed in Table 1 of 
this AD to do the inspection.

Initial Inspection--Previous Credit

    (h) Propeller hubs, P/N 660709201, that previously passed 
inspection using Dowty Alert SBs listed in Table 1 of this AD or an 
earlier issue of those SBs, have satisfied the initial inspection 
requirements of this AD. However, you must comply with the 
repetitive inspection requirements found in this AD.

Repetitive Ultrasonic Inspections

    (i) Thereafter, perform a repetitive ultrasonic inspection of 
the rear wall of the rear half of the propeller hub for cracks 
within the compliance time specified in Table 1 of this AD. Use 
Appendix A or Appendix D of the applicable Dowty Alert SB listed in 
Table 1 of this AD to do the inspection.

Optional Terminating Action

    (j) As optional terminating action for the repetitive 
inspections required by this AD, replace propeller hub, P/N 
660709201, with a new propeller hub, P/N 660717226.

Alternative Methods of Compliance (AMOCs)

    (k) The Manager, Boston Certification Office, has the authority 
to approve AMOCs for this AD if requested using the procedures found 
in 14 CFR 39.19.

Related Information

    (l) For more information about this AD, contact Michael Schwetz, 
Aerospace Engineer, Boston Aircraft Certification Office, FAA, 12 
New England Executive Park, Burlington, MA 01803; phone: 781-238-
7761; fax: 781-238-7170; e-mail: michael.schwetz@faa.gov.
    (m) European Aviation Safety Agency 2010-0196R1, dated November 
12, 2010, pertains to the subject of this AD.
    (n) For service information identified in this AD, contact Dowty 
Propellers, Anson Business Park, Cheltenham Road East, Gloucester GL 
29QN, UK; telephone: 44 (0) 1452 716000; fax: 44 (0) 1452 716001. 
You may review copies of the referenced service information at the 
FAA, Engine & Propeller Directorate, 12 New England Executive Park, 
Burlington, MA. For information on the availability of this material 
at the FAA, call 781-238-7125.

    Issued in Burlington, Massachusetts, on April 7, 2011.
Peter A. White,
Acting Manager, Engine & Propeller Directorate, Aircraft Certification 
Service.
[FR Doc. 2011-9258 Filed 4-15-11; 8:45 am]
BILLING CODE 4910-13-P


