[Federal Register Volume 64, Number 211 (Tuesday, November 2, 1999)]
[Proposed Rules]
[Pages 59137-59139]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-28522]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 97-ANE-09]
Airworthiness Directives; Rolls-Royce plc Model RB211 Trent 892,
884, 877, 875, and 892B Series Turbofan Engines
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: This document proposes to revise an existing airworthiness
directive (AD), 97-06-13, applicable to certain Rolls-Royce plc (R-R)
RB.211 Trent 800 series turbofan engines, that currently requires
initial and repetitive inspections of the angled drive upper shroud,
the intermediate gearbox housing (IGH), and the external gearbox lower
bevel box (LBB) housing. In addition, that AD requires initial and
repetitive master magnetic chip detector (MCD) inspections. Finally,
prior to initiation of Extended-Range Operations with Two-Engine
Aircraft (ETOPS), or prior to September 30, 1997, whichever occurs
first, AD 97-06-13 requires installation of a redesigned angled drive
upper shroud tube and a lower splitter fairing with revised sealing.
This action would eliminate the repetitive inspections of the IGH,
external gearbox LBB housing, and the angled drive upper shroud, if the
engines have incorporated modifications described in certain R-R
Service Bulletins (SBs) . In addition, this action would increase the
inspection interval for repetitive master MCD inspections. This
proposal is prompted by service experience since publication of AD 97-
06-13. The actions specified by the proposed AD are intended to prevent
loss of oil, which could cause an engine fire. This proposed AD is also
intended to prevent in-flight engine shutdowns and airplane diversions
caused by oil loss and bearing failures.
DATES: Comments must be received by January 3, 2000.
ADDRESSES: Submit comments to the Federal Aviation Administration
(FAA), New England Region, Office of the Regional Counsel, Attention:
Rules Docket No. 97-ANE-09, 12 New England Executive Park, Burlington,
MA 01803-5299. Comments may also be sent via the Internet using the
following address: 9-ane-adcomment@faa.gov''. Comments sent via the
Internet must contain the docket number in the subject line. Comments
may be inspected at this location between 8:00 a.m. and 4:30 p.m.,
Monday through Friday, except Federal holidays.
The service information referenced in the proposed rule may be
obtained from Rolls-Royce North America, Inc., 2001 South Tibbs Ave.,
Indianapolis, IN 46241; telephone (317) 230-3995, fax (317) 230-4743.
This information may be examined at the FAA, New England Region, Office
of the Regional Counsel, 12 New England Executive Park, Burlington, MA.
FOR FURTHER INFORMATION CONTACT: Jason Yang, Aerospace Engineer, Engine
Certification Office, FAA, Engine and Propeller Directorate, 12 New
England Executive Park, Burlington, MA 01803-5299; telephone (781) 238-
7747, fax (781) 238-7199.
SUPPLEMENTARY INFORMATION:
Comments Invited
Interested persons are invited to participate in the making of the
proposed rule by submitting such written data, views, or arguments as
they may desire. Communications should identify the Rules Docket number
and be submitted to the address specified above. All communications
received on or before the closing date
[[Page 59138]]
for comments, specified above, will be considered before taking action
on the proposed rule. The proposals contained in this notice may be
changed in light of the comments received.
Comments are specifically invited on the overall regulatory,
economic, environmental, and energy aspects of the proposed rule. All
comments submitted will be available, both before and after the closing
date for comments, in the Rules Docket for examination by interested
persons. A report summarizing each FAA-public contact concerned with
the substance of this proposal will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments
submitted in response to this notice must submit a self-addressed,
stamped postcard on which the following statement is made: ``Comments
to Docket Number 97-ANE-09.'' The postcard will be date-stamped and
returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this NPRM by submitting a request
to the FAA, New England Region, Office of the Regional Counsel,
Attention: Rules Docket No. 97-ANE-09, 12 New England Executive Park,
Burlington, MA 01803-5299.
Discussion
On April 14, 1997, the Federal Aviation Administration (FAA) issued
airworthiness directive (AD) 97-06-13, Amendment 39-9970 (62 FR 23339,
April 30, 1997), applicable to Rolls-Royce plc (R-R) Model RB211 Trent
892, 884, 877, 875, and 892B series turbofan engines. That AD requires
initial and repetitive visual and fluorescent penetrant inspections
(FPI) of the angled drive upper shroud tube for fretting and cracking,
initial and repetitive visual inspections and FPI for cracking, a one-
time FPI for porosity of the intermediate gearbox housing (IGH), and
initial and repetitive visual inspections for cracking of the external
gearbox lower bevel box (LBB) housing. In addition, AD 97-06-13
requires initial and repetitive master magnetic chip detector (MCD)
inspections. Finally, prior to initiation of Extended-Range Operations
with Two-Engine Aircraft (ETOPS), or prior to September 30, 1997,
whichever occurs first, AD 97-06-13 requires installation of a
redesigned angled drive upper shroud tube and a lower splitter fairing
with revised sealing. That action was prompted by reports of loss of
oil from the angle drive upper shroud tube, the IGH, the LBB, and by
reports of bearing failures. That condition, if not corrected, could
result in loss of oil, which could cause an engine fire. That
condition, if also not corrected, could result in in-flight engine
shutdowns and airplane diversions caused by oil loss and bearing
failures.
Service Experience Since Publication of AD 97-06-13
Since the issuance of that AD, the Civil Aviation Authority (CAA)
of the United Kingdom and the FAA have received service experience
reports from operators that indicate that certain aspects of the
current AD may be relaxed.
Relaxatory Actions
This proposal would exempt engines that have incorporated
modifications described in certain R-R Service Bulletins (SBs) from the
repetitive visual inspections and FPI of the IGH and external gearbox
LBB housing. In addition, this proposal would increase the inspection
interval for repetitive master MCD inspections.
New Service Bulletins (SBs)
R-R has issued SB RB.211-72-C114, Revision 2, dated March 13, 1998,
that introduces a transfer tube and a lower splitter fairing with
revised sealing; SB RB.211-72-C220, dated April 18, 1997, that
introduces a low vibration angled drive shaft; and SB RB.211-72-C197,
March 4, 1997, and SB RB.211-72-C211, dated March 21, 1997, that
introduce a strengthened gearbox housing assembly.
Proposed Actions
Since an unsafe condition has been identified that is likely to
exist or develop on other products of this same type design, the
proposed AD would revise AD 97-06-13 to continue to require the
inspections of the current AD. However, engines that have incorporated
modifications described by the R-R SBs listed in the New Service
Bulletins paragraph of the discussion section would be exempt from the
repetitive inspections of the angled drive upper shroud, IGH, and
external gearbox LBB housing described in proposed paragraphs (a) and
(b). In addition, the repetitive inspection interval for the master MCD
inspections described in proposed paragraph (c) would be increased to
250 hours time-in-service (TIS). The actions would be required to be
accomplished in accordance with the SBs described previously.
Economic Analysis
The FAA estimates that 24 engines installed on aircraft of U.S.
registry would be affected by this proposed AD, that it would take
approximately 18 work hours per engine to accomplish the optional
modifications, and that the average labor rate is $60 per work hour.
Required parts would cost approximately $23,000 per engine. Based on
these figures, the total cost impact of the proposed AD on US operators
is estimated to be $577,920. However, since these modifications are
optional, operators may continue to perform the repetitive inspections
required by proposed paragraph (b) at no additional cost.
Regulatory Impact
The regulations proposed herein would not have substantial direct
effects 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. Therefore, in
accordance with Executive Order 12612, it is determined that this
proposal would not have sufficient federalism implications to warrant
the preparation of a Federalism Assessment.
For the reasons discussed above, I certify that this 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) if promulgated, 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. A copy of the draft
regulatory evaluation prepared for this action is contained in the
Rules Docket. A copy of it may be obtained by contacting the Rules
Docket at the location provided under the caption ADDRESSES.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration proposes to amend
part 39 of the Federal Aviation Regulations (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.
[[Page 59139]]
Sec. 39.13 [Amended]
2. Section 39.13 is amended by removing Amendment 39-9970 (62 FR
23339, April 30, 1997), and by adding a new airworthiness directive, to
read as follows:
Rolls-Royce plc: Docket No. 97-ANE-09. Revises AD 97-06-13,
Amendment 39-9970.
Applicability: Rolls-Royce plc (R-R) Model RB211 Trent 892, 884,
877, 875, and 892B series turbofan engines, installed on but not
limited to Boeing 777 series aircraft.
Note 1: This airworthiness directive (AD) applies to each engine
identified in the preceding applicability provision, regardless of
whether it has been modified, altered, or repaired in the area
subject to the requirements of this AD. For engines that have been
modified, altered, or repaired so that the performance of the
requirements of this AD is affected, the owner/operator must request
approval for an alternative method of compliance in accordance with
paragraph (d) of this AD. The request should include an assessment
of the effect of the modification, alteration, or repair on the
unsafe condition addressed by this AD; and, if the unsafe condition
has not been eliminated, the request should include specific
proposed actions to address it.
Compliance: Required as indicated, unless accomplished
previously.
To prevent loss of oil, which could cause an engine fire, and
in-flight engine shutdowns and airplane diversions caused by oil
loss and bearing failures, accomplish the following:
Currently Required Actions
(a) Inspect angle drive upper shroud tubes as follows:
(1) Within 50 cycles-in-service (CIS) after May 15, 1997, the
effective date of AD 97-06-13, visually inspect and measure the
fretting and fluorescent penetrant inspect (FPI) for cracks the
angle drive upper shroud tubes in accordance with R-R Service
Bulletin (SB) No. RB.211-72-C089, Revision 1, dated January 24,
1997.
(2) Thereafter, at intervals not to exceed 50 CIS since last
inspection, visually inspect and measure the fretting and FPI for
cracks in the angled drive upper shroud tubes, in accordance with R-
R SB No. RB.211-72-C089, Revision 1, dated January 24, 1997.
(3) Prior to further flight, remove from service angled drive
upper shroud tubes that exhibit fretting measured in excess of 0.020
inches, or any cracks, and replace with serviceable parts.
(4) Installation of an improved angled drive upper shroud tube
with a lower splitter fairing with revised sealing in accordance
with R-R SB No. RB.211-72-C114, Revision 2, dated March 13, 1998,
constitutes terminating action to the requirements of this
paragraph.
(5) Prior to initiation of Extended-Range Operations with Two-
Engine Aircraft (ETOPS), or prior to September 30, 1997, whichever
occurs first, install an improved angled drive upper shroud tube
with a lower splitter fairing with revised sealing in accordance
with R-R SB No. RB.211-72-C114, Revision 2, dated March 13, 1998.
(b) Inspect the intermediate gearbox housing (IGH) and external
gearbox lower bevel box (LBB) housing as follows:
(1) Within 5 CIS after May 15, 1997, the effective date of AD
97-06-13, perform an initial visual inspection of the IGH and LBB
housing for cracks, in accordance with R-R Mandatory SB No. RB.211-
72-C129, Revision 2, dated March 21, 1997.
(2) Within 10 CIS after May 15, 1997, the effective date of AD
97-06-13, perform an initial FPI of the IGH for cracks, in
accordance with R-R Mandatory SB No. RB.211-72-C129, Revision 2,
dated March 21, 1997.
(3) Thereafter, at intervals not to exceed 5 CIS since last
visual inspection, visually inspect the IGH and LBB housing for
cracks, and at intervals not to exceed 10 CIS since last FPI, FPI
the IGH, in accordance with R-R Mandatory SB No. RB.211-72-C129,
Revision 2, dated March 21, 1997.
(4) Within 10 CIS after May 15, 1997, the effective date of AD
97-06-13, perform an FPI of the IGH for porosity in accordance with
R-R Mandatory SB No. RB.211-72-C129, Revision 2, dated March 21,
1997.
(5) Within the next 5 CIS after May 15, 1997, the effective date
of AD 97-06-13, remove from service IGHs that exhibit porosity
levels in excess of the acceptable criteria listed in the SB and
replace with serviceable parts.
(6) Prior to further flight, remove from service cracked IGHs
and LLB housings and replace with serviceable parts.
Optional Terminating Action to Paragraph (b) Requirements
(7) Incorporation of modifications described in R-R SB RB.211-
72-C220, dated April 18, 1997, which introduces a low vibration
angled drive shaft; and R-R SB RB.211-72-C197, March 4, 1997, which
introduces IGH assembly with increased wall thickness, or SB RB.211-
72-C211, dated March 21, 1997, which introduces a strengthened
gearbox housing assembly , are incorporated, constitute terminating
action to the requirements of this paragraph.
Master Magnetic Chip Detector (MCD) Inspections
(c) Inspect the Master MCD as follows:
(1) Within 100 hours time-in-service (TIS) after May 15, 1997,
the effective date of AD 97-06-13, perform an initial inspection of
the Master MCD in accordance with Mandatory SB No. RB.211-79-C093,
Revision 1, February 28, 1997.
Extended Master MCD Repetitive Inspection Interval
(2) Thereafter, at intervals not to exceed 250 hours TIS since
last inspection, perform repetitive inspections of the Master MCD in
accordance with Mandatory SB No. RB.211-79-C093, Revision 1, dated
February 28, 1997.
Alternative Method of Compliance
(d) An alternative method of compliance or adjustment of the
compliance time that provides an acceptable level of safety may be
used if approved by the Manager, Engine Certification Office (ECO).
Operators shall submit their request through an appropriate FAA
Principal Maintenance Inspector, who may add comments and then send
it to the Manager, ECO.
Note 2: Information concerning the existence of approved
alternative methods of compliance with this airworthiness directive,
if any, may be obtained from the ECO.
Ferry Flights
(e) Special flight permits may be issued in accordance with
Secs. 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR
21.197 and 21.199) to operate the aircraft to a location where the
inspection requirements of this AD can be accomplished.
Issued in Burlington, Massachusetts, on October 25, 1999.
David A. Downey,
Assistant Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 99-28522 Filed 11-1-99; 8:45 am]
BILLING CODE 4910-13-U
