AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Hartzell Propeller, Inc. propeller models HC-(1,D)2(X,V,MV)20-7, HC-
(1,D)2(X,V,MV)20-8, and HC-(1,D)3(X,V,MV)20-8. This AD was prompted by
failures of the propeller hydraulic bladder diaphragm and resulting
engine oil leak. This AD requires replacement of the propeller
hydraulic bladder diaphragm. We are issuing this AD to prevent
propeller hydraulic bladder diaphragm rupture, loss of engine oil,
damage to the engine, and loss of the airplane.

DATES: This AD is effective August 30, 2013.

ADDRESSES: For service information identified in this AD, contact
Hartzell Propeller, Inc., 1 Propeller Place, Piqua, OH 45356; phone:
937-778-4397; fax: 937-778-4391; email: techsupport@hartzellprop.com.
You may view this service information at the FAA, 12 New England
Executive Park, Burlington, MA. For information on the availability of
this material at the FAA, call 781-238-7125.
The Docket Operations office is located at Docket Management
Facility, U.S. Department of Transportation, Docket Operations, M-30,
West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue SE.,
Washington, DC 20590.

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 AD, the regulatory evaluation,
any comments received, and other information. The address for the
Docket Office (phone: 800-647-5527) provided in the ADDRESSES section.
Comments will be available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Mark Grace, Aerospace Engineer,
Chicago Aircraft Certification Office, FAA, Propulsion Branch, 2300 E.
Devon Avenue, Des Planes, IL 60018; phone: 847-294-7377; fax: 847-294-
7834; email: mark.grace@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 to include an AD that would apply to the specified products.
The NPRM published in the Federal Register on March 26, 2013 (78 FR
18255). The NPRM proposed to require replacement of the propeller
hydraulic bladder diaphragm with a redesigned bladder diaphragm that
includes a tab, visible after installation, which contains the bladder
diaphragm batch/lot number.

Comments

We gave the public the opportunity to participate in developing
this AD. We have considered the comment received. Hartzell Propeller,
Inc. supports the NPRM (78 FR 18255, dated March 26, 2013).

Conclusion

We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
this AD as proposed.

Costs of Compliance

We estimate that this AD will affect about 400 propellers installed
on airplanes of U.S. registry. We also estimate that it will take about
4 hours per propeller to replace the bladder diaphragm. The average
labor rate is $85 per hour. We estimate parts costs at $53 per engine.
Based on these figures, we estimate the cost of this AD on U.S.
operators to be $157,200. Our cost estimate is exclusive of possible
warranty coverage.

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

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,
(2) Is not a ``significant rule'' under DOT Regulatory Policies and
Procedures (44 FR 11034, February 26, 1979),
(3) Will not affect intrastate aviation in Alaska to the extent
that it justifies making a regulatory distinction, 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.

Adoption of 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

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 adding the following new airworthiness
directive (AD):