[Federal Register: May 18, 2004 (Volume 69, Number 96)]
[Proposed Rules]
[Page 28094-28098]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr18my04-15]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 2004-NE-19-AD]
RIN 2120-AA64
Airworthiness Directives; Rolls-Royce plc RB211-524 Series
Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to supersede an existing airworthiness
directive (AD) for Rolls-Royce plc (RR) RB211-524 series turbofan
engines. That AD currently requires initial and repetitive borescope
inspections of the head section and meterpanel assembly of the
combustion liner, and replacement, if necessary, with serviceable
parts. In addition, that AD allows an optional installation of a front
combustion liner with a strengthened head section as a terminating
action to the inspection requirements. This proposed AD would require
initial and repetitive borescope inspections of the head section and
meterpanel assembly of the combustion liner, and replacement, if
necessary, with serviceable parts, reduction of the inspection
intervals of certain RB211-524 engine models that have not been
repaired to RR Field Repair Scheme FRS5367/B, and a mandatory
terminating action to be completed by a certain date. This proposed AD
results from five events that are directly attributed to combustor head
break-up and meterpanel failure which were found at overhaul
inspection. At least one of these events resulted in a combustion case
burn-through. We are proposing this AD to prevent engine combustion
liner deterioration, which can result in combustion liner breakup, case
burn-through, and engine fire.
DATES: We must receive any comments on this proposed AD by July 19,
2004.
[[Page 28095]]
ADDRESSES: Use one of the following addresses to submit comments on
this proposed AD:
By mail: Federal Aviation Administration (FAA), New
England Region, Office of the Regional Counsel, Attention: Rules Docket
No. 2004-NE-19-AD, 12 New England Executive Park, Burlington, MA 01803-
5299.
By fax: (781) 238-7055.
By e-mail: 9-ane-adcomment@faa.gov.
You can get the service information identified in this proposed AD
from Rolls-Royce plc, P.O. Box 31, Derby, DE24 8BJ, United Kingdom;
telephone: 011-44-1332-242424; fax: 011-44-1332-249936.
You may examine the AD docket, by appointment, at the FAA, New
England Region, Office of the Regional Counsel, 12 New England
Executive Park, Burlington, MA.
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 ``AD Docket No. 2004-NE-19-AD'' in the
subject line of your comments. If you want us to acknowledge receipt of
your mailed comments, send us a self-addressed, stamped postcard with
the docket number written on it; we will date-stamp your postcard and
mail it back to you. We specifically invite comments on the overall
regulatory, economic, environmental, and energy aspects of the proposed
AD. If a person contacts us verbally, and that contact relates to a
substantive part of this proposed AD, we will summarize the contact and
place the summary in the docket. We will consider all comments received
by the closing date and may amend the proposed AD in light of those
comments.
We are reviewing the writing style we currently use in regulatory
documents. We are interested in your comments on whether the style of
this document is clear, and your suggestions to improve the clarity of
our communications that affect you. You may get more information about
plain language at http://www.faa.gov/language and http://www
.plainlanguage.gov.
Examining the AD Docket
You may examine the AD Docket (including any comments and service
information), by appointment, between 8 a.m. and 4:30 p.m., Monday
through Friday, except Federal holidays. See ADDRESSES for the
location.
Discussion
On March 26, 1997, the FAA issued AD 97-07-04, Amendment 39-9978
(62 FR 16475, April 7, 1997). That AD requires initial and repetitive
borescope inspections of the head section and meterpanel assembly of
the combustion liner, and replacement, if necessary, with serviceable
parts. In addition, that AD allows an optional installation of a front
combustion liner with a strengthened head section as a terminating
action to the inspection requirements.
Actions After AD 97-07-04 Was Issued
After AD 97-07-04 was issued, the Civil Aviation Authority (CAA),
which is the airworthiness authority for the United Kingdom (U.K.),
notified the FAA that an unsafe condition may exist on RR RB211-524
series turbofan engines. The CAA advises that in August 2002, an RB211-
524B engine suffered a combustion case burn-through as a result of
combustor head break-up. The combustor head had been previously
inspected within the inspection interval specified in RR Service
Bulletin (SB) No. RB.211-72-B482, Revision 8, dated November 15, 2001,
only 228 cycles before the event. Subsequent to the original AD, RR has
issued several revisions to SB No. RB.211-72-B482 to expand the
applicability and clarify or revise the inspection requirements. In
2003, RR issued Alert Service Bulletin (ASB) No. RB.211-72-AB482,
Revision 9, dated July 28, 2003, to reduce the inspection interval for
RB211-524B-02, -524B2, -524B3, and -524B4 engines that have not been
repaired to RR Field Repair Scheme FRS5367/B. This condition, if not
corrected, could result in engine combustion liner deterioration, which
can result in combustion liner breakup, case burn-through, and engine
fire.
Relevant Service Information
We have reviewed and approved the technical contents of the
following RR SBs:
RR ASB No. RB.211-72-AB482, Revision 9, dated July 28,
2003, that describes the initial inspection procedures for the
combustion liner head section and the meterpanel cracking. This ASB
also describes the compliance intervals to do the initial and
repetitive inspections.
RR SB No. RB.211-72-9670, dated August 27, 1993, that
describes the procedures to incorporate the improved combustion liner
head with C263 material, and to incorporate local thickened diffuser
walls around the struts for engine models -524B-02, -524B2, -524B3, -
524B4, -524C2 and -524D4.
RR SB No. RB.211-72-9764, Revision 3, dated January 16,
1998, that describes the procedures to incorporate the improved
combustion liner with strengthened head and improved heat shields for
engine models -524G and -524H.
The CAA classified ASB No. RB.211-72-AB482, Revision 9, dated July
28, 2003, as mandatory and issued AD G-2003-0011 (previously 005-07-
95), dated October 1, 2003, in order to ensure the airworthiness of
these RR engines in the U.K.
Bilateral Agreement Information
This engine model is manufactured in the U.K. and is type
certificated for operation in the United States under the provisions of
Sec. 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 has kept the FAA informed of
the situation described above. We have examined the findings of the
CAA, 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.
FAA's Determination and Requirements of the Proposed AD
We have evaluated all pertinent information and identified an
unsafe condition that is likely to exist or develop on other products
of this same type design. Therefore, we are proposing this AD, which
would require the following:
Initial and repetitive borescope inspections of the head
section and meterpanel assembly of the combustion liner, and
replacement, if necessary, with serviceable parts;
Reduction of the inspection intervals of certain RB211-524
engine models that have not been repaired to RR Field Repair Scheme
FRS5367/B; and,
A mandatory terminating action to the repetitive
inspections to be completed within 10,000 CSN or no later than December
31, 2012.
The proposed AD would require that you do these actions using the
service information described previously.
[[Page 28096]]
Costs of Compliance
There are about 537 RB211-524 series turbofan engines of the
affected design in the worldwide fleet. We estimate that 18 engines
installed on airplanes of U.S. registry would be affected by this
proposed AD. We also estimate that it would take approximately 2.0 work
hours per engine to perform the proposed actions, and that the average
labor rate is $65 per work hour. Required parts would cost about
$228,389 per engine. Based on these figures, we estimate the total cost
of the proposed AD to U.S. operators to be $4,113,351.
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 by
sending a request to us at the address listed under ADDRESSES. Include
``AD Docket No. 2004-NE-19-AD'' in your request.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
The Proposed Amendment
Accordingly, 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 removing Amendment 39-9978 (62 FR
16475, April 7, 1997) and by adding a new airworthiness directive, to
read as follows:
Rolls-Royce plc: Docket No. 2004-NE-19-AD. Supersedes AD 97-07-04,
Amendment 39-9978.
Comments Due Date
(a) The Federal Aviation Administration (FAA) must receive
comments on this airworthiness directive (AD) action by July 19,
2004.
Affected ADs
(b) This AD supersedes AD 97-07-04, Amendment 39-9978.
Applicability
(c) This AD applies to Rolls-Royce plc (RR) engine models RB211-
524B-02, -524B2, -524B3, -524B4, -524C2, -524D4 series engines
incorporating RR Service Bulletin (SB) No. RB.211-72-7221 or RR SB
No. RB.211-72-7998 with front combustion liner assembly, part number
(P/N) UL16885, UL26916, UL27107, UL28972 or UL28974 installed but
not incorporating RR SB No. RB.211-72-9670 or RR SB No. RB.211-72-
9764, and engine models RB211-524G and -524H series engines with
front combustion liner assembly P/N UL27659, UL23992, or UL22988 but
not incorporating RR SB No. RB.211-72-9764. These engines are
installed on, but not limited to, Boeing 747 and Lockheed L1011
series airplanes.
Unsafe Condition
(d) This AD results from five events that are directly
attributed to combustor head break-up and meterpanel failure which
were found at overhaul inspection. At least one of these events
resulted in a combustion case burn-through. The actions specified in
this AD are intended to prevent engine combustion liner
deterioration, which can result in combustion liner breakup, case
burn-through, and engine fire.
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. Engine inspections previously made
to Rolls-Royce plc (RR) Service Bulletin RB.211-72-B482, Revision 8,
can be credited for counting cycles since last inspection.
Inspections of Combustion Liner Head Sections--Not Previously Repaired
(f) Borescope-inspect combustion liner head sections that have
not been previously repaired. Use paragraphs 3.A.(1) through 3.A.(5)
of the Accomplishment Instructions of RR Alert Service Bulletin
(ASB) No. RB.211-72-AB482, Revision 9, dated July 28, 2003, and the
compliance thresholds in Table 1 of this AD.
Table 1.--Combustor Head Section--Not Previously Repaired
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Parts exceeding initial
Initial inspection Repetitive inspection inspection cycles
Engine series (cycles-since-new (cycles-since-last- (cycles-in-service
(CSN)) inspection (CSLI)) (CIS))
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(1) RB211-524C2, -524D4, -524G, and - Within 1,400 to 1,600 Within 200 CSLI........ Within 100 CIS after
524H. CSN. effective date of this
AD.
(2) RB211-524B-02, -524B2, -524B3, Within 3,000 to 3,200 Within 200 CSLI........ Within 200 CIS after
and -524B4. CSN. the effective date of
this AD.
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Inspections of Combustion Head Sections--Previously Repaired Using RR
Field Repair Scheme FRS5367/B
(g) Borescope-inspect combustion liner head sections previously
repaired using RR Field Repair Scheme FRS5367/B. Use paragraphs
3.A.(1) through 3.A.(5) of the Accomplishment Instructions of RR ASB
No. RB.211-72-AB482, Revision 9, dated July 28, 2003, and the
compliance thresholds in Table 2 of this AD.
Table 2.--Combustor Head Section--Previously Repaired Using RR Field Repair Scheme FRS5367/B
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Parts exceeding initial
Initial inspection Repetitive inspection inspection cycles
Engine series (cycles-since-last (cycles-since-last- (cycles-in-service
repair (CSLR)) inspection (CSLI)) (CIS))
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(1) RB211-524C2, -524D4, -524G, and - Within 1,800 to 2,200 Within 400 CSLI........ Within 200 CIS after
524H. CSLR. the effective date of
this AD.
[[Page 28097]]
(2) RB211-524B-02, -524B2, -524B3, Within 3,000 to 3,200 Within 400 CSLI........ Within 200 CIS after
and -524B4. CSLR. the effective date of
this AD.
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Inspections of Combustion Head Sections That Have Been Repaired But Did
Not Use RR Field Repair Scheme FRS5367/B
(h) Borescope-inspect combustion liner head sections that have
been repaired using a method other than RR Field Repair Scheme
FRS5367/B. Use paragraph 3.A.(1) through 3.A.(5) of the
Accomplishment Instructions of RR ASB No. RB.211-72-AB482, Revision
9, dated July 28, 2003, and the compliance thresholds in Table 3 of
this AD.
Table 3.--Combustor Head Section--Repaired, But Did Not Use RR Field Repair Scheme FRS5367/B
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Parts exceeding initial
Initial inspection Repetitive inspection inspection cycles
Engine series cycles (cycles-since- cycles (cycles-since- (cycles-in-service
last repair (CSLR)) last-inspection (CSLI)) (CIS))
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(1) RB211-524C2, -524D4, -524G, and - Within 500 to 700 CSLR. Within 200 CSLI........ Within 100 CIS after
524H. the efffective date of
this AD.
(2) RB211-524B-02, -524B2, -524B3, Within 2,000 to 2,200 Within 200 CSLI........ Within 200 CIS after
and -524B4. CSLR. the effective date of
this AD.
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Note 1: For an installed front combustion liner that is subject
to RR ASB No. RB.211-72-AB482, Revision 9, dated July 28, 2003: If
the operator can confirm with the relevant overhaul base or repair
vendor that the nicrobraze repair RR Field Repair Scheme FRS5367 has
been applied to all 18 struts, then this is equivalent to compliance
with RR Field Repair Scheme FRS5367/B.
Note 2: Head sections repaired by replacement of all 18 struts
using RR Field Repair Scheme FRS6548 are considered as equivalent to
fitting a new head section for inspection purposes.
Inspections of Meterpanel Assemblies--Not Repaired
(i) Borescope-inspect meterpanel assemblies, incorporating
Service Bulletin (SB) No. RB.211-72-7998, that have not been
previously repaired. Use paragraph 3.B.(1) through 3.B.(7) of the
Accomplishment Instructions of RR ASB No. RB.211-72-AB482, Revision
9, dated July 28, 2003, and the compliance thresholds in Table 4 of
this AD.
Table 4.--Meterpanel Assembly--Not Repaired
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Parts exceeding initial
Initial inspection Repetitive inspection inspection cycles
Engine series cycles-since-new (CSN) cycles (cycles-since- (cycles-in-service
last-inspection (CSLI)) (CIS))
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(1) RB211-524D4, -524G, and -524H.... Within 1,000 to 1,200 Within 400 CSLI........ Within 50 CIS after the
CSN. effective date of this
AD.
(2) RB211-524D4, -524G, and -524H Within 1,800 to 2,000 Within 400 CSLI........ Within 50 CIS after the
that have not used RB211-524H CSN. effective date of this
ratings at any time. AD.
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Inspections of Meterpanel Assemblies--Repaired
(j) Borescope-inspect meterpanel assemblies, incorporating
Service Bulletin (SB) No. RB.211-72-7998, that have been previously
repaired. Use paragraph 3.B.(1) through 3.B.(7) of the
Accomplishment Instructions of RR ASB No. RB.211-72-AB482, Revision
9, dated July 28, 2003, and the compliance thresholds in Table 5 of
this AD.
Table 5.--Meterpanel Assembly--Repaired
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Parts exceeding initial
Initial inspection Repetitive inspection inspection cycles
Engine series cycles (cycles-since- cycles (cycles-since- (cycles-in-service
last repair (CSLR)) last-inspection (CSLI)) (CIS))
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(1) RB211-524D4, -524G, and -524H.... Within 500 to 700 CSLR. Within 400 CSLI........ Within 50 CIS after the
effective date of this
AD.
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Note 3: There is no requirement to inspect meter panels for
combustors to a pre-RR SB No. RB.211-72-7998 standard.
Reject Parts
(k) Replace parts that exceed the acceptance criteria.
Information about the acceptance criteria can be found in the
Aircraft Maintenance Manual, 72-00-00, Inspection/Check.
Mandatory Terminating Action
(l) Replace any front combustion liner assembly that has a P/N
listed in paragraph (c) of this AD at the next shop visit or within
10,000 CSN but no later than December 31, 2012.
(m) Replacement of the front combustion liner assembly with a
front combustion liner assembly that incorporates the modifications
in RR SB No. RB.211-72-9670 or RR SB No. RB.211-72-9764 in the
RB211-524B02, -524B2, -B3, -B4, -C2 and D4 engines
[[Page 28098]]
constitutes terminating action to the repetitive inspections in
paragraphs (f), (g), (h), (i), and (j), of this AD.
(n) Replacement of the front combustion liner assembly with a
front combustion liner assembly that incorporates the modifications
in RR SB No. RB.211-72-9764 in the RB211-524G and -524H engines
constitutes terminating action to the repetitive inspections in
paragraphs (f), (g), (h), (i), and (j) of this AD.
Definition of Shop Visit
(o) For the purpose of this AD, a shop visit is defined as any
time that the 04 module is removed for refurbishment or overhaul.
Alternative Methods of Compliance
(p) 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.
Material Incorporated by Reference
(q) You must use Rolls-Royce plc (RR) Alert Service Bulletin No.
RB.211-72-AB482, Revision 9, dated July 28, 2003; RR Service
Bulletin (SB) No. RB.211-71-9670, dated August 27, 1993; and RR SB
No. RB.211-72-9764, Revision 3, dated January 16, 1998 to do the
inspections and replacements required by this AD. Approval of
incorporation by reference from the Office of the Federal Register
is pending.
Related Information
(r) Civil Aviation Authority airworthiness directive AD G-2003-
0011 (previously 005-07-95), dated October 1, 2003, also addresses
the subject of this AD. Aircraft Maintenance Manual 72-00-00 also
addresses the subject of this AD.
Issued in Burlington, Massachusetts, on May 12, 2004.
Peter A. White,
Acting Manager, Engine and Propeller Directorate, Aircraft
Certification Service.
[FR Doc. 04-11200 Filed 5-17-04; 8:45 am]
BILLING CODE 4910-13-P