[Federal Register: December 27, 2004 (Volume 69, Number 247)]
[Proposed Rules]
[Page 77144-77146]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr27de04-9]
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Proposed Rules
Federal Register
________________________________________________________________________
This section of the FEDERAL REGISTER contains notices to the public of
the proposed issuance of rules and regulations. The purpose of these
notices is to give interested persons an opportunity to participate in
the rule making prior to the adoption of the final rules.
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[[Page 77144]]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2004-19930; Directorate Identifier 2004-NE-33-AD]
RIN 2120-AA64
Airworthiness Directives; Rolls-Royce plc RB211 Trent 800 Series
Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for Rolls-Royce plc (RR) RB211 Trent 800 series turbofan engines. This
proposed AD would require initial and repetitive borescope inspections
of the high pressure-and-intermediate pressure (HP-IP) turbine internal
and external oil vent tubes for coking and carbon buildup, and cleaning
or replacing the vent tubes if necessary. This proposed AD results from
a report of an RB211 Trent 700 series engine experiencing a disk shaft
separation, overspeed of the IP turbine rotor, and multiple blade
release of IP turbine blades. Preliminary findings suggest these events
resulted from an internal oil fire in the HP-IP turbine oil vent tubes
due to coking and carbon buildup. This fire led to a second fire in the
internal air cavity below the IP turbine disk drive shaft. We are
proposing this AD to prevent internal oil fires in RB211 Trent 800
series turbofan engines due to coking and carbon buildup, that could
cause uncontained engine failure and damage to the airplane.
DATES: We must receive any comments on this proposed AD by February 25,
2005.
ADDRESSES: Use one of the following addresses to comment on this
proposed AD.
DOT Docket Web Site: Go to http://dms.dot.gov and follow
the instructions for sending your comments electronically.
Government-wide Rulemaking Web Site: Go to http://www.regulations.gov
and follow the instructions for sending your
comments electronically.
Mail: Docket Management Facility; U.S. Department of
Transportation, 400 Seventh Street, SW., Nassif Building, Room PL-401,
Washington, DC 20590-001.
Fax: (202) 493-2251.
Hand Delivery: Room PL-401 on the plaza level of the
Nassif Building, 400 Seventh Street, SW., Washington, DC, between 9
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
Contact Rolls-Royce plc, PO Box 31, Derby, England; telephone: 011-
44-1332-249428; fax: 011-44-1332-249223 for the service information
identified in this proposed AD.
FOR FURTHER INFORMATION CONTACT: Ian Dargin, Aerospace Engineer, Engine
Certification Office, FAA, Engine and Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-
7178; fax (781) 238-7199.
SUPPLEMENTARY INFORMATION:
Comments Invited
We invite you to submit any written relevant data, views, or
arguments regarding this proposal. Send your comments to an address
listed under ADDRESSES. Include ``Docket No. FAA-2004-19930;
Directorate Identifier 2004-NE-33-AD'' in the subject line of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of the proposed AD. We will
consider all comments received by the closing date and may amend the
proposed AD in light of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov
, including any personal information you provide. We will
also post a report summarizing each substantive verbal contact with FAA
personnel concerning this proposed AD. Using the search function of the
DMS Web site, anyone can find and read the comments in any of our
dockets, including the name of the individual who sent the comment (or
signed the comment on behalf of an association, business, labor union,
etc.). You may review the DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78) or you
may visit http://dms.dot.gov.
Examining the AD Docket
You may examine the docket that contains the proposal, any comments
received, and any final disposition in person at the DMS Docket Offices
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The Docket Office (telephone (800) 647-5227) is on the plaza
level of the Department of Transportation Nassif Building at the street
address stated in ADDRESSES. Comments will be available in the AD
docket shortly after the DMS receives them.
Discussion
As a member of the National Transportation Safety Board (NTSB)
investigation team, we are investigating an incident event on RR RB211
Trent 700 series engines and possible unsafe condition on RB211 Trent
800 series engines. The Civil Aviation Authority (CAA), which is the
airworthiness authority for the United Kingdom (UK) is helping us
investigate. A report was received of an RB211 Trent 700 series engine
experiencing a disk shaft separation, overspeed of the IP turbine
rotor, and multiple blade release of IP turbine blades. Preliminary
findings suggest these events resulted from an internal oil fire in the
HP-IP turbine oil vent tubes due to coking and carbon buildup. This
fire led to a second fire in the internal air cavity below the IP
turbine disk drive shaft. Because the oil vent tubes on the event
engine were destroyed, the partner engine on the same airplane was
inspected. That inspection revealed heavy coking and carbon buildup,
with partial blockage of the HP-IP turbine oil vent tubes. Both engines
had the same on-wing life of 15,169 hours with 2,344 cycles-since-new.
Both engines contained Mobil Jet Oil 291, which also is suspect and
will be removed from the list of approved oils for these engines. The
NTSB investigation is ongoing and a probable cause finding has not yet
been made. The fire, disk overspeed, and blade release appear to be the
result of the coking and carbon buildup, evident in the sister engine
and linked by cycles and oil use to the event engine. The Trent 800
series engines have similar
[[Page 77145]]
design HP-IP turbine oil vent tubes and are the subject of this
proposed AD.
Relevant Service Information
We have reviewed and approved the technical contents of RR Alert
Service Bulletin (ASB) No. RB.211-72-AE362, dated May 7, 2004, that
describes procedures for:
Initial and repetitive borescope inspections for coking
and carbon buildup in the HP-IP turbine oil vent tubes; and
Cleaning the tubes if necessary, and removing the engine
from service to clean or replace the tubes.
This ASB requires that all operators submit inspection data to the
manufacturer. The CAA classified this ASB as mandatory and issued AD G-
2004-0009, dated May 27, 2004, in order to ensure the airworthiness of
these RB211 Trent 800 series engines in the UK.
Differences Between This Proposed AD and the Manufacturer's Service
Information
Although RR ASB No. RB.211-72-AE362, dated May 7, 2004, requires
replacing the scavenge oil filter and sending the removed filter to RR
for examination as part of returning the engine to service, this
proposed AD does not require sending the removed filter to RR.
FAA's Determination and Requirements of the Proposed AD
These Trent 800 series engines, manufactured in the U.K., are type-
certificated for operation in the United States under the provisions of
section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and
the applicable bilateral airworthiness agreement. In keeping with this
bilateral airworthiness agreement, the CAA kept us informed of the
situation described above. We have examined the CAA's findings,
reviewed all available information, and determined that AD action is
necessary for products of this type design that are certificated for
operation in the United States. For this reason, we are proposing this
AD, which would require:
Initial and repetitive borescope inspections of the HP-IP
turbine oil vent tubes for coking and carbon buildup; and
Cleaning the oil vent tubes or removing the engine from
service if the tubes fail the inspection.
Interim Action
These actions are interim actions and we may take further
rulemaking actions in the future.
Costs of Compliance
There are about 420 RB211 Trent 800 series engines of the affected
design in the worldwide fleet. We estimate that this proposed AD would
affect 120 engines installed on airplanes of U.S. registry. We also
estimate that it would take about 1.5 work hours per engine to perform
the proposed on-wing inspections, and about 0.5 work hour to perform
the proposed in-shop inspections. The average labor rate is $65 per
work hour. Based on these figures, we estimate the total cost for U.S.
operators to perform one on-wing inspection to be $11,700, and the
total cost to perform one in-shop inspection to be $3,900.
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 have determined that this proposed AD would not have federalism
implications under Executive Order 13132. This proposed AD would 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 the proposed
regulation:
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. Would 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 summary of the costs to comply with this proposal and
placed it in the AD Docket. You may get a copy of this summary at the
address listed under ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Under the authority delegated to me by the Administrator, the
Federal Aviation Administration proposes to amend 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:
Rolls-Royce plc: Docket No. FAA-2004-19930; Directorate Identifier
2004-NE-33-AD.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive comments
on this airworthiness directive (AD) action by February 25, 2005.
Affected ADs
(b) None.
Applicability: (c) This AD applies to Rolls-Royce plc (RR) RB211
Trent 875-17, 877-17, 884-17, 884B-17, 892-17, 892B-17, and 895-17
series turbofan engines. These engines are installed on, but not
limited to, Boeing 777 airplanes.
Unsafe Condition
(d) This AD results from a report of an RB211 Trent 700 series
engine experiencing a disk shaft separation, overspeed of the IP
turbine rotor, and multiple blade release of IP turbine blades.
Preliminary findings suggest these events resulted from an internal oil
fire in the HP-IP turbine oil vent tubes due to coking and carbon
buildup. This fire led to a second fire in the internal air cavity
below the IP turbine disk drive shaft. We are issuing this AD to
prevent internal oil fires in RB211 Trent 800 series turbofan engines
due to coking and carbon buildup, that could cause uncontained engine
failure and damage to the airplane.
Compliance: (e) You are responsible for having the actions required
by this AD performed within the compliance times specified unless the
actions have already been done.
[[Page 77146]]
Initial Visual Inspection
(f) Using paragraph 3.A. (on-wing) or 3.B. (in-shop) of
Accomplishment Instructions of RR Alert Service Bulletin (ASB) RB.211-
72-AE362, dated May 7, 2004, and the inspection schedule in Table 1 of
this AD, perform an initial borescope inspection of the high pressure-
and-intermediate pressure (HP-IP) turbine internal and external oil
vent tubes for coking and carbon buildup as follows:
(1) Insert an 8 mm diameter flex borescope to see if it will pass
along the full length of the vent tube into the bearing chamber.
(2) If the vent tube prevents an 8 mm diameter flex borescope from
passing along the full length of the tube into the bearing chamber,
repeat the action using a 6 mm flex borescope.
(3) If the 6 mm diameter flex borescope passes through to the
bearing chamber, continue using the engine in service, and perform the
repetitive inspections in this AD at the required intervals specified
in Table 2 of this AD.
(4) If the vent tube prevents the 6 mm diameter flex borescope from
passing along the full length of the tube into the bearing chamber,
remove the engine from service within 10 cycles-since-last inspection
(CSLI).
Table 1.--Initial Inspection Schedule
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If the engine or the 05 module: Then initially inspect:
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Has reached the threshold life of Within 1,000 hours time-in-
15,000 hours time-since new (TSN) or service (TIS) or 200 cycles-in
reached the threshold life of 3,000 service (CIS) after the
cycles-since-new (CSN) on the effective date of this AD,
effective date of this AD. whichever occurs first.
Has fewer than 15,000 hours TSN or Within 1,000 hours TIS or 200
fewer than 3,000 CSN on the effective CIS after reaching the
date of this AD. threshold life.
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Repetitive Visual Inspections
(g) Using paragraph 3.A. (on-wing) or 3.B. (in-shop) of
Accomplishment Instructions of RR ASB RB.211-72-AE362, dated May 7,
2004, paragraphs (f)(1) through (f)(4) of this AD, and the inspection
schedule in Table 2 of this AD, perform repetitive borescope
inspections of the HP-IP turbine internal and external oil vent tubes
for coking and carbon buildup.
Table 2.--Repetitive Inspection Schedule
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If at the previous inspection, before
any cleaning was performed: Then:
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(1) There was no coking and carbon Reinspect within 6,000 hours
buildup of a visible thickness; or an time-since-last-inspection
8 mm diameter flex borescope could (TSLI) or within 1,200 cycles-
pass along the full length of the since-last-inspection (CSLI),
internal vent tube into the bearing whichever occurs first.
chamber.
(2) The coking or carbon buildup Reinspect within 1,500 hours
prevented an 8 mm diameter flex TSLI or within 300 CSLI,
borescope from passing through the whichever occurs first.
internal vent tube, but a 6 mm
diameter flex borescope could pass
along the full length of the internal
vent tube into the bearing chamber.
(3) The coking or carbon buildup Remove the engine from service
prevented the 6 mm diameter flex within 10 CSLI.
borescope from passing through the
full length of the internal vent tube
and into the bearing chamber.
------------------------------------------------------------------------
Reporting Requirements
(h) Report findings of the inspection to Rolls-Royce using Table 1
(On-wing Inspection Findings) or Table 2 (In-shop Inspection Findings)
of RR ASB RB.211-72-AE362, dated May 7, 2004. The Office of Management
and Budget (OMB) has approved the reporting requirements specified in
Table 1 and Table 2 of RR ASB RB.211-72-AE362, dated May 7, 2004, and
assigned OMB control number 2120-0056.
Alternative Methods of Compliance
(i) The Manager, Engine Certification Office, has the authority to
approve alternative methods of compliance for this AD if requested
using the procedures found in 14 CFR 39.19.
Related Information
(j) CAA airworthiness directive No. G-2004-0009, dated May 27,
2004, also addresses the subject of this AD.
Issued in Burlington, Massachusetts, on December 17, 2004.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 04-28145 Filed 12-23-04; 8:45 am]
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