[Federal Register Volume 76, Number 102 (Thursday, May 26, 2011)]
[Rules and Regulations]
[Pages 30529-30531]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2011-13014]
-----------------------------------------------------------------------
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-0994; Directorate Identifier 2009-NE-39-AD;
Amendment 39-16707; AD 2011-11-08]
RIN 2120-AA64
Airworthiness Directives; Rolls-Royce plc (RR) RB211-535 Series
Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
-----------------------------------------------------------------------
SUMMARY: We are adopting a new airworthiness directive (AD) for the
products listed above. This AD results from mandatory continuing
airworthiness information (MCAI) issued by an aviation authority of
another country to identify and correct an unsafe condition on an
aviation product. The MCAI describes the unsafe condition as:
There have been several findings of cracking at the firtrees of
LP Turbine discs. Fatigue crack initiation and subsequent crack
propagation at the firtree may result in multiple LP Turbine blade
release. The latter may potentially be beyond the containment
capabilities of the engine casings. Thus, cracking at the firtrees
of LP Turbine discs constitutes a potentially unsafe condition.
We are issuing this AD to detect cracks in the low-pressure (LP)
turbine stage 1, 2, and 3 discs, which could result in an uncontained
release of LP turbine blades and damage to the airplane.
DATES: This AD becomes effective June 30, 2011.
ADDRESSES: The Docket Operations office is located at Docket Management
Facility, U.S. Department of Transportation, 1200 New Jersey Avenue,
SE., West Building Ground
[[Page 30530]]
Floor, Room W12-140, Washington, DC 20590-0001.
FOR FURTHER INFORMATION CONTACT: Frederick Zink, Aerospace Engineer,
Engine Certification Office, FAA, Engine and Propeller Directorate, 12
New England Executive Park, Burlington, MA 01803; e-mail:
[email protected]; telephone (781) 238-7779; fax (781) 238-7199.
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.
That NPRM was published in the Federal Register on October 5, 2010 (75
FR 61361). That NPRM proposed to correct an unsafe condition for the
specified products. The MCAI states:
There have been several findings of cracking at the firtrees of
LP Turbine discs. Fatigue crack initiation and subsequent crack
propagation at the firtree may result in multiple LP Turbine blade
release. The latter may potentially be beyond the containment
capabilities of the engine casings. Thus, cracking at the firtrees
of LP Turbine discs constitutes a potentially unsafe condition.
Therefore this Airworthiness Directive requires a change to the
inspection intervals of LP Turbine Discs.
Comments
We gave the public the opportunity to participate in developing
this AD. We considered the comments received.
Request To Change Related Information Paragraph
One commenter, Rolls-Royce plc asked us to use a different
statement for Rolls-Royce contact information in paragraph (i) of the
proposed AD. Rolls-Royce is concerned that responses to requests for
information will be delayed if the statement is not clear on how to
request information on service bulletins.
We partially agree. Paragraph (i) is now paragraph (j) of this AD,
and we have changed paragraph (j) of the AD to supply the relevant
contact information.
Support for the Proposed AD as Written
Two commenters, Continental Airlines and The Boeing Company support
the proposed AD as written.
Request To Change the Definition of a Shop Visit
Three commenters, FedEx, American Airlines, and Rolls-Royce plc
asked us to change the definition of a shop visit to the definition in
the Rolls-Royce Alert Service Bulletin (ASB) RB.211-72-AG272,''at every
engine refurbishment and at every 04 and 05 Module Level 3
(Refurbishment) or Level 4 (Overhaul) shop visit.'' The commenters
believed that the proposed AD definition of a shop visit is too
conservative and will result in unnecessarily increased costs without a
significant improvement in safety.
We partially agree. We agree that the current definition in the
proposed AD is too broad because inspecting the LP turbine disks every
time an unrelated major flange is separated is not required. We
disagree with using the definition in the service bulletin because the
service bulletin definition is not sufficient for our needs. We changed
paragraph (f) of the proposed AD to ``For the purpose of this AD, an
``engine shop visit'' is the induction of an engine into the shop for
maintenance involving the separation of the intermediate-pressure/low-
pressure (IP/LP) turbine module from the engine, separation of the IP
turbine case from the combustion outer case, or separation of the LP
turbine case from the IP turbine case, except that the separation of
engine flanges solely for the purposes of transportation without
subsequent engine maintenance does not constitute an engine shop
visit.''
Request To Clarify the Compliance Time
One commenter, American Airlines, asked us to clarify the
compliance time in paragraph (e)(1) of the proposed AD to state that
for engines currently in the shop on the effective date of the AD, the
initial inspection is to be carried out if the affected parts are
exposed and rebuild has not yet started. The commenter believed that
the proposed AD is unclear as to whether engines which have begun their
shop visits prior to the effective date of the AD are required to
undergo the initial inspection before re-introduction into service.
We agree. Engines currently in the shop at piece part exposure or
in a condition prior to, must comply with the AD before any approval
for return to service. Engines built up beyond this point will not
require compliance with the AD until the next piece part exposure.
Engines that are in the shop and have been approved for return to
service are considered not to be in the shop. We changed paragraph (f)
of the proposed AD to clarify a shop visit.
Request To Change the Initial Inspection Requirements
One commenter, American Airlines, asked us to change the initial
inspection requirements in paragraph (e)(1) of the proposed AD to
specify ``paragraphs 3.C through 3.E.'' in ASB RR.211-72-AG272, instead
of ``Section 3.'' The commenter believed that only Section 3.C. through
3.E. address the unsafe condition.
We partially agree. The ASB we reference in paragraph (e)(1) of the
proposed AD is not incorporated by reference, so requiring operators to
follow specific paragraphs in the ASB is unnecessary. We agree,
however, that including the reference may induce confusion. We deleted
the reference from the proposed AD.
Request To Change the Costs of Compliance
One commenter, American Airlines, asked us to change the Costs of
Compliance Section of the proposed AD. American Airlines stated the
number of 90 products installed on U.S. registered airplanes and the
number of work-hours for performing the inspections are incorrect.
American Airlines stated that they operate more RB211-535 engines than
the number listed in the proposed AD. American Airlines also stated
that ASB RB.211-72-AG272 lists the total hour for accomplishing the
required actions as 70 work-hours. American Airlines requests that the
AD reflect the work-hours required as 70 work-hours if limited to
refurbishment shop visits. If non-refurbishment shop visits are
included, American Airlines estimates the average work-hours at 1,300
hours per shop visit.
We partially agree. As of July 9, 2010, 588 installed engines were
on U.S. registered airplanes. We changed the Costs of Compliance
Section from ``90 products of U.S. registry'' to ``588 products of U.S.
registry.'' We also changed the ``cost of the AD on U.S. operators''
from $229,500 to $1,499,400.
We don't agree with the request to change the time to comply if
performed during non-refurbishment shop visits. We base the number of
hours in the cost estimate on performing the inspection during the next
shop visit as defined in this AD. We made no change to the AD.
Conclusion
We reviewed the available data, including the comments received,
and determined that air safety and the public interest require adopting
the AD with the changes described previously. We determined that these
changes will not increase the scope of the AD.
Costs of Compliance
Based on the service information, we estimate that this AD would
affect about 588 products installed on airplanes of U.S. registry. We
also estimate that it would take about 30 work-hours per product to
comply with this AD. The average labor rate is $85 per work-hour.
[[Page 30531]]
Required parts would cost about $0 per product. Based on these figures,
we estimate the cost of the AD on U.S. operators to be $1,499,400.
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 determined that 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 this AD:
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); and
3. 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.
We prepared a regulatory evaluation of the estimated costs to
comply with this AD and placed it in the AD docket.
Examining the AD Docket
You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Operations office
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 street address for
the Docket Operations office (phone (800) 647-5527) is provided in the
ADDRESSES section. Comments will be available in the AD docket shortly
after receipt.
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
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 AD:
2011-11-08 Rolls-Royce plc: Amendment 39-16707. Docket No. FAA-2010-
0994; Directorate Identifier 2009-NE-39-AD.
Effective Date
(a) This airworthiness directive (AD) becomes effective June 30,
2011.
Affected ADs
(b) None.
Applicability
(c) This AD applies to Rolls-Royce plc RB211-535E4-37, -535E4-B-
37, -535E4-B-75, and -535E4-C-37 turbofan engines. These engines are
installed on, but not limited to, Boeing 757-200 series, -200PF
series, -200CB series, and -300 series airplanes and Tupolev Tu204
series airplanes.
Reason
(d) This AD results from several findings of cracking at the
firtrees of low-pressure (LP) turbine discs. Fatigue crack
initiation and subsequent crack propagation at the firtree may
result in multiple LP turbine blade release. We are issuing this AD
to detect cracks in the LP turbine stage 1, 2, and 3 discs, which
could result in an uncontained release of LP turbine blades and
damage to the airplane.
Actions and Compliance
(e) Unless already done, do the following actions.
Initial Inspection Requirements
(1) At the next engine shop visit after the effective date of
this AD, perform a visual and a fluorescent penetrant inspection
(FPI) of the LP turbine stage 1, 2, and 3 disc.
Repeat Inspection Requirements
(2) At each engine shop visit after accumulating 1,500 cycles
since the last inspection of the LP turbine stage 1, 2 and 3 discs,
repeat the inspections specified in paragraph (e)(1) of this AD.
Remove Cracked Discs
(3) If you find cracks, remove the disc from service.
Definitions
(f) For the purpose of this AD, an ``engine shop visit'' is:
(1) Induction of an engine into the shop for maintenance
involving the separation of the intermediate-pressure/low-pressure
(IP/LP) turbine module from the engine, or
(2) Separation of the IP turbine case from the combustion outer
case, or
(3) Separation of the LP turbine case from the IP turbine case,
except that the separation of engine flanges solely for the purposes
of transportation without subsequent engine maintenance does not
constitute an engine shop visit.
(g) Engines that have been approved for return to service but
are still physically in the shop are not considered to be in the
shop.
FAA AD Differences
(h) This AD differs from the Mandatory Continuing Airworthiness
Information (MCAI) and or service information as follows in that
while the MCAI compliance requires action at a current shop visit,
this AD requires compliance at the next shop visit after the
effective date of this AD.
Other FAA AD Provisions
(i) Alternative Methods of Compliance (AMOCs): The Manager,
Engine Certification Office, FAA, has the authority to approve AMOCs
for this AD, if requested using the procedures found in 14 CFR
39.19.
Related Information
(j) Refer to MCAI European Aviation Safety Agency Airworthiness
Directive 2009-0244, dated November 9, 2009, and Rolls-Royce plc
Alert Service Bulletin No. RB.211-72-AG272 for related information.
Contact Rolls-Royce plc., P.O. Box 31, Derby, DE24 8BJ, United
Kingdom; phone: 011 44 1332 242424, fax: 011 44 1332 249936; or e-
mail from:http://www.rollsroyce.com/contact/civil_team.jsp, for a
copy of this service information or download the publication from
https://www.aeromanager.com.
(k) Contact Frederick Zink, Aerospace Engineer, Engine
Certification Office, FAA, Engine and Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803; e-mail:
[email protected]; telephone (781) 238-7779; fax (781) 238-
7199, for more information about this AD.
Material Incorporated by Reference
(l) None.
Issued in Burlington, Massachusetts, on May 20, 2011.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 2011-13014 Filed 5-25-11; 8:45 am]
BILLING CODE 4910-13-P