DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0750; Product Identifier 2017-NE-24-AD; Amendment
39-19137; AD 2017-26-06]
RIN 2120-AA64

Airworthiness Directives; Rolls-Royce Corporation Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are adopting a new airworthiness directive (AD) for certain
Rolls-Royce Corporation (RRC) AE 3007A and AE 3007C model turbofan
engines. This AD was prompted by an updated analysis that lowered the
life limit of fan wheels installed on the affected engines. This AD
requires removal of the affected fan wheel at new, lower life limits.
We are issuing this AD to address the unsafe condition on these
products.

DATES: This AD is effective January 31, 2018.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of January 31,
2018.

ADDRESSES: For service information identified in this final rule,
contact Rolls-Royce Corporation, 450 South Meridian Street, Mail Code
NB-02-05, Indianapolis, IN 46225; phone: 317-230-3774; email:
indy.pubs.services@rolls-royce.com; internet: www.rolls-royce.com. You
may view this service information at the FAA, Engine and Propeller
Standards Branch, 1200 District Avenue, 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 by searching for and locating Docket No. FAA-2017-0750;
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 final rule, the regulatory evaluation, any comments
received, and other information. The address for the Docket Office
(phone: 800-647-5527) is Document 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.

FOR FURTHER INFORMATION CONTACT: Kyri Zaroyiannis, Aerospace Engineer,
Chicago ACO Branch, FAA, 2300 E. Devon Ave., Des Plaines, IL 60018;
phone: 847-294-7836; fax: 847-294-7834; email:
kyri.zaroyiannis@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR
part 39 by adding an AD that would apply to certain RRC AE 3007A and AE
3007C model turbofan engines. The NPRM published in the Federal
Register on September 22, 2017 (82 FR 44357). The NPRM was prompted by
an updated stress analysis that showed higher stress than previously
calculated in the aft retainer flange scallop of the fan wheel, part
number (P/N) 23061670. As a result, RRC reduced the published life of
the affected fan wheel. The NPRM proposed to require removal of the
affected fan wheel at new, lower life limits. We are issuing this AD to
correct the unsafe condition on these products.

Comments

We gave the public the opportunity to participate in developing
this final rule. We have considered the comment received. The Air Line
Pilots Association supported the NPRM.

Conclusion

We reviewed the relevant data, considered the comment received, and
determined that air safety and the public interest require adopting
this final rule as proposed except for minor editorial changes. We have
determined that these minor changes:
Are consistent with the intent that was proposed in the
NPRM for correcting the unsafe condition; and
Do not add any additional burden upon the public than was
already proposed in the NPRM.

Related Service Information Under 1 CFR Part 51

We reviewed RRC Alert Service Bulletin (ASB) AE 3007A-A-72-424/ASB
AE 3007C-A-72-327 (one document), Revision 1, dated April 20, 2017. The
ASB provides updated life limits for the affected fan wheels. 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 the ADDRESSES section.

Costs of Compliance

We estimate that this AD affects 341 engines installed on airplanes
of U.S. registry.
We estimate the following costs to comply with this AD:

Estimated Costs

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.
This AD is issued in accordance with authority delegated by the
Executive Director, Aircraft Certification Service, as authorized by
FAA Order 8000.51C. In accordance with that order, issuance of ADs is
normally a function of the Compliance and Airworthiness Division, but
during this transition period, the Executive Director has delegated the
authority to issue ADs applicable to engines, propellers, and
associated appliances to the Manager, Engine and Propeller Standards
Branch, Policy and Innovation Division.

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, 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):