DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2017-0254; Product Identifier 2017-NE-10-AD; Amendment
39-19066; AD 2017-20-09]
RIN 2120-AA64

Airworthiness Directives; General Electric Company 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 all
General Electric Company (GE) CF34-8E model turbofan engines. This AD
was prompted by a report that using a certain repair procedure for the
fan outlet guide vane (OGV) frame could alter the strength capability
of the fan OGV frame. This AD requires replacement of all fan OGV
frames repaired using this procedure. We are issuing this AD to address the
unsafe condition on these products.

DATES: This AD is effective November 13, 2017.

ADDRESSES: For service information identified in this final rule,
contact General Electric Company, GE-Aviation, Room 285, 1 Neumann Way,
Cincinnati, OH 45215, phone: 513-552-3272; fax: 513-552-3329; email:
geae.aoc@ge.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. It is also available on the internet at
http://www.regulations.gov by searching for and locating Docket No.
FAA-2017-0254.

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-2017-0254;
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: David Bethka, Aerospace Engineer,
ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-
238-7129; fax: 781-238-7199; email: david.bethka@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 all GE CF34-8E model
turbofan engines. The NPRM published in the Federal Register on June 8,
2017 (82 FR 26615). The NPRM was prompted by a report that using a
certain repair procedure for the fan OGV frame could alter the strength
capability of the fan OGV frame because the repair procedure included
an improper heat cycle. The NPRM proposed to require replacement of all
fan OGV frames repaired using this procedure. This condition, if not
corrected, could result in failure of the fan OGV frame, engine
separation, and loss of the airplane.

Comments

We gave the public the opportunity to participate in developing
this final rule. The following presents the comments received on the
NPRM and the FAA's response to each comment.

Support for the NPRM

The Air Line Pilots Association supports the NPRM.

Request To Change Applicability

Horizon Air requested we include a list of fan OGV frame affected
serial numbers (S/Ns) in this AD. J-Air requested that this AD include
GE Service Bulletin (SB) CF34-8E-AL S/B 72-0183, Revision 3, dated
March 7, 2017, for a list of affected OGV frame S/Ns known to GE.
Further, the two commenters explained that operators are not
necessarily aware of which repairs have been performed. The changes
were requested to take the burden off the operator to determine AD
applicability.
We partially agree. We disagree that SB CF34-8E-AL S/B 72-0183
provides a list of all affected OGV frame S/Ns. The list of known
affected part S/Ns is based on the best available data, but is not
comprehensive. It may be possible that some OGV frames were repaired,
but are not known to GE and are not included in GE SB CF34-8E-AL S/B
72-0183. Operators are responsible for checking engine records to
determine AD applicability.
We agree to unburden operators to the maximum extent possible. In
the interest of aiding operators to determine affected part S/Ns, we
included GE SB CF34-8E-AL S/B 72-0183 in the Related Service
Information section in the preamble of this final rule, with a note
that GE SB CF34-8E-AL S/B 72-0183 does not include a comprehensive list
of all affected parts. GE SB CF34-8E-AL S/B 72-0183 includes a list of
OGV frame S/Ns known to GE that have been repaired to GEK 112031 72-00-
23, REPAIR 006.

Conclusion

We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
this final rule with the change described previously. We have
determined that these minor changes:
[Agr]re 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.
We also determined that these changes will not increase the
economic burden on any operator or increase the scope of this final
rule.

Related Service Information

We reviewed GE CF34-8E Engine Manual, GEK 112031, 72-00-23, REPAIR
006. The repair describes procedures for applying a dry-film lubricant
to the fan OGV frame with heat curing.
We also reviewed GE SB CF34-8E-AL S/B 72-0183, Revision 3, dated
March 7, 2017. The SB provides instructions to replace the fan OGV
frames repaired as specified in GE CF34-8E Engine Manual, GEK 112031,
72-00-23, REPAIR 006. However, the SB does not provide a comprehensive
list of affected parts. The SB provides a list of OGV frame S/Ns known
to GE that have been repaired to GEK 112031 72-00-23 REPAIR 006.

Costs of Compliance

We estimate that this AD affects 42 engines installed on airplanes
of U.S. registry.
We estimate the following costs to comply with this AD:

Estimated Costs

According to the manufacturer, some of the costs of this AD may be
covered under warranty, thereby reducing the cost impact on affected
individuals. We do not control warranty coverage for affected
individuals. As a result, we have included all costs in our cost
estimate.

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):