[Federal Register Volume 81, Number 16 (Tuesday, January 26, 2016)]
[Rules and Regulations]
[Pages 4165-4167]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-01268]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2015-3585; Directorate Identifier 2015-NE-22-AD;
Amendment 39-18384; AD 2015-28-01]
RIN 2120-AA64
Airworthiness Directives; Engine Alliance 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
Engine Alliance (EA) GP7270 turbofan engines. This AD was prompted by
the manufacturer informing us that the inspection criteria and repair
procedures in the maintenance manual for aft bolt holes of the high-
pressure compressor (HPC) cone shaft on the affected engines is
incorrect. This AD requires inspection of the HPC cone shaft and repair
of affected parts, if needed. We are issuing this AD to prevent failure
of the HPC cone shaft, which could lead to uncontained engine failure
and damage to the airplane.
DATES: This AD is effective March 1, 2016.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of March 1,
2016.
ADDRESSES: For service information identified in this AD, contact
Engine Alliance, 400 Main St., East Hartford, CT 06108, M/S 169-10,
phone: 800-565-0140; email: [email protected]; Internet:
sp.engineallianceportal.com. You may view this service information at
the FAA, Engine & Propeller Directorate, 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-2015-
3585; 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) 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: Kyle Gustafson, Aerospace Engineer,
Engine & Propeller Directorate, FAA, 1200 District Avenue, Burlington,
MA 01803; phone: 781-238-7183; fax: 781-238-7199; email:
[email protected].
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 EA GP7270 turbofan
engines. The NPRM published in the Federal Register on October 1, 2015
(80 FR 59081). The NPRM was prompted by the manufacturer informing us
that the inspection criteria and repair procedures in the maintenance
manual for aft bolt holes of the HPC cone shaft, also referred to as
the ``HPC forward stubshaft,'' for the affected engines is incorrect.
The NPRM proposed to require inspection of the HPC cone shaft and
repair of affected parts, if needed. We are issuing this AD to prevent
failure of the HPC cone shaft, which could lead to uncontained engine
failure and damage to the airplane.
Comments
We gave the public the opportunity to participate in developing
this AD. The following presents the comments received on the NPRM (80
FR 59081, October 1, 2015) and the FAA's response to each comment.
Request To Add Engine Models
EA requested that we expand the applicability to include the GP7272
and GP7277 engine models.
We disagree. There are no GP7272 or GP7277 engines in service nor
have any been delivered. New engines would be delivered with corrected
service
[[Page 4166]]
information and would not be impacted by this AD. We did not change
this AD.
Request To Change the Unsafe Condition Statement
EA requested that the unsafe condition statement be changed from
``We are issuing this AD to prevent failure of the HPC cone shaft,
which could lead to uncontained engine failure and damage to the
airplane.'' to ``We are issuing this AD to prevent a hazardous engine
condition.'' The reason for this request is that no HPC cone shaft
failures have occurred in the field.
We disagree. The unsafe condition statement describes the condition
we are trying to prevent and is the justification for this AD. It does
not describe what has occurred in the past. We did not change this AD.
Request To Change Various Paragraphs
EA requested that we revise the part nomenclature in the
Applicability, Compliance, and Installation Prohibition paragraphs and
in the unsafe condition statement to include both ``cone shaft'' and
``forward stubshaft.'' The part is referenced as a ``cone shaft'' in
this AD and engine and component manuals; however, it is referred to as
a ``forward stubshaft'' in the service bulletins (SBs).
We disagree. The part nomenclature listed in the airworthiness
limitations section and engine maintenance manual is ``cone shaft.''
The Discussion section of this AD explains that the terms ``cone
shaft'' and ``forward stubshaft'' are synonymous. We consider including
both terms throughout this AD unnecessary. We did not change this AD.
Request To Revise the Compliance
EA requested that the Compliance paragraph be revised to include
the word ``pits'' when describing the inspection criteria.
We agree. We revised paragraph (e)(1) and (f)(1) of this AD from
``. . . nicks, dents, and scratches . . .'' to ``. . . nicks, dents,
pits, and scratches. . . .''
Request To Change the Compliance
EA requested that we replace ``Do not reinstall the HPC cone shaft
if the aft bolt hole has a nick, dent, or scratch that is greater than
0.002 inch in depth'' in paragraph (e)(1) of this AD with ``Comply with
the Accomplishment Instructions in EA SB No. EAGP7-72-330 if the aft
bolt hole has a nick, dent, pit, or scratch that is greater than the
serviceable limit.''
We disagree. The current engine manual has an approved repair
procedure for damage that is more severe than the installation
requirements of this AD. It is not necessary to restate what is already
allowed by the engine manual. We did not change this AD.
Request To Change Service Information
EA requested that the phrase ``or later'' be used when referring to
SBs.
We disagree. We are only authorized to mandate use of SBs that we
have reviewed and which are published. Since future revisions of SBs
are not yet published, we are not authorized to mandate their use. We
did not change this AD.
Request To Change the Installation Prohibition
EA requested that we change the Installation Prohibition paragraph
to read: ``After the effective date of this AD, do not install an HPC
cone shaft onto an engine: (1) that has accumulated more than 9,000
cycles since new that has not complied with this AD on an applicable
part, and (2) has a nick, dent, or scratch in an HPC cone shaft aft
bolt hole that is greater than the serviceable limit.''
We disagree. The intent of the Installation Prohibition paragraph
is to mandate the new serviceable limit of 0.002 inch for damage to the
inner diameter of the bolt holes for the entire GP7270 fleet. Any parts
with damage beyond this limit may be repaired using the approved
procedures listed in the engine manual, provided that you include shot
peening as required by paragraph (f)(2) of this AD. We did not change
this AD.
Conclusion
We reviewed the relevant data, considered the comments received,
and determined that air safety and the public interest require adopting
this AD with the changes described previously.
We also determined that these changes will not increase the
economic burden on any operator or increase the scope of this AD.
Related Service Information Under 1 CFR Part 51
EA has issued SB No. EAGP7-72-329, dated July 21, 2015 and SB No.
EAGP7-72-330, dated July 21, 2015. The service information describes
procedures for shotpeening the HPC forward stubshaft and inspecting the
HPC forward stubshaft bolt-hole inner diameter respectively. 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 of this final rule.
Costs of Compliance
We estimate that this AD affects zero engines installed on
airplanes of U.S. registry. The average labor rate is $85 per hour.
Based on these figures, we estimate the cost of this AD on U.S.
operators to be $0.
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:
[[Page 4167]]
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 (AD):
2015-28-01 Engine Alliance: Amendment 39-18384; Docket No. FAA-2015-
3585; Directorate Identifier 2015-NE-22-AD.
(a) Effective Date
This AD is effective March 1, 2016.
(b) Affected ADs
None.
(c) Applicability
This AD applies to Engine Alliance (EA) GP7270 turbofan engines
with a high-pressure compressor (HPC) cone shaft, part number 382-
100-907-0, installed.
(d) Unsafe Condition
This AD was prompted by the manufacturer informing us that the
inspection and repair criteria in the maintenance manual for aft
bolt holes of the HPC cone shaft on the affected engines is
incorrect. We are issuing this AD to prevent failure of the HPC cone
shaft, which could lead to uncontained engine failure and damage to
the airplane.
(e) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(1) For HPC cone shafts with serial numbers listed in EA Service
Bulletin (SB) No. EAGP7-72-330, dated July 21, 2015, inspect the
inner diameter of the HPC cone shaft aft bolt holes for nicks,
dents, pits, and scratches before accumulating 9,000 cycles since
new (CSN). Do not reinstall the HPC cone shaft if the aft bolt hole
has any nicks, dents, pits, or scratches that are greater than 0.002
inch in depth.
(2) For HPC cone shafts with serial numbers listed in EA SB No.
EAGP7-72-329, dated July 21, 2015, shot peen the HPC cone shaft aft
bolt holes before accumulating 9,000 CSN. Use paragraph 1 of the
Accomplishment Instructions in EA SB No. EAGP7-72-329 to do the shot
peening.
(f) Installation Prohibition
After the effective date of this AD, do not install an HPC cone
shaft on any engine with the following:
(1) any nicks, dents, pits, or scratches in an HPC cone shaft
aft bolt hole that is greater than 0.002 inch in depth; or
(2) any repair of an HPC cone shaft aft bolt hole that did not
include shot peening.
(g) Alternative Methods of Compliance (AMOCs)
The Manager, Engine Certification Office, may approve AMOCs for
this AD. Use the procedures found in 14 CFR 39.19 to make your
request. You may email your request to: [email protected].
(h) Related Information
For more information about this AD, contact Kyle Gustafson,
Aerospace Engineer, Engine & Propeller Directorate, FAA, 1200
District Avenue, Burlington, MA 01803; phone: 781-238-7183; fax:
781-238-7199; email: [email protected].
(i) 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) Engine Alliance (EA) Service Bulletin (SB) No. EAGP7-72-329,
dated July 21, 2015.
(ii) EA SB No. EAGP7-72-330, dated July 21, 2015.
(3) For EA service information identified in this AD, contact
Engine Alliance, 400 Main St., East Hartford, CT 06108, M/S 169-10;
phone: 800-565-0140; email: [email protected]; Internet:
sp.engineallianceportal.com.
(4) You may view this service information at FAA, Engine &
Propeller Directorate, 1200 District Avenue, Burlington, MA. For
information on the availability of this material at the FAA, call
781-238-7125.
(5) You may view this service information at the National
Archives and Records Administration (NARA). For information on the
availability of this material at NARA, call 202-741-6030, or go to:
http://www.archives.gov/federal-register/cfr/ibr-locations.html.
Issued in Burlington, Massachusetts, on January 13, 2016.
Gaetano Sciortino,
Acting Directorate Manager, Engine & Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 2016-01268 Filed 1-25-16; 8:45 am]
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