[Federal Register Volume 70, Number 144 (Thursday, July 28, 2005)]
[Proposed Rules]
[Pages 43659-43661]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-14803]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2003-NE-12-AD]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce plc RB211 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) RB211-22B series, RB211-524B, -
524C2, -524D4, -524G2, -524G3, and -524H series, and RB211-535C and -
535E series turbofan engines with high pressure compressor (HPC) stage 
3 disc assemblies, part numbers (P/Ns) LK46210, LK58278, LK67634, 
LK76036, UL11706, UL15358, UL22577, UL22578, and UL24738 installed. 
That AD requires removing from service certain disc assemblies before 
they reach their full life if not modified with anticorrosion 
protection. This proposed AD would require the same actions as AD 2004-
01-20, but would shorten the compliance time for disks that entered 
service before 1990. This proposed AD results from the manufacturer's 
reassessment of the corrosion risk on HPC stage 3 disc assemblies not 
modified with sufficient application of anticorrosion protection. We 
are issuing this AD to prevent corrosion-induced uncontained disc 
failure, resulting in damage to the airplane.

DATES: We must receive comments on this proposed AD by September 26, 
2005.

ADDRESSES: Use one of the following addresses to comment on this 
proposed AD:
     By mail: Federal Aviation Administration (FAA), New 
England Region, Office of the Regional Counsel, Attention: Rules Docket 
No. 2003-NE-12-AD, 12 New England Executive Park, Burlington, MA 01803-
5299.
     By fax: (781) 238-7055.
     By e-mail: [email protected].
    You can get the service information identified in this proposed AD 
from Rolls-Royce plc, PO Box 31, Derby, England, DE248BJ; telephone: 
011-44-1332-242424; fax: 011-44-1332-245-418.
    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 send any written relevant data, views, or 
arguments regarding this proposal. Send your comments to an address 
listed under ADDRESSES. Include ``AD Docket No. 2003-NE-12-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.

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 January 8, 2004, we issued AD 2004-01-20, Amendment 39-13434 (69 
FR 2661, January 20, 2004). That AD allows certain disc assemblies to 
reach their full life only after modifying the disc assemblies with 
anticorrosion protection. The Civil Aviation Authority (CAA), which is 
the airworthiness authority for the United Kingdom, notified the FAA 
that an unsafe condition may exist on RR RB211-22B series, RB211-524B, 
-524C2, -524D4, -524G2, -524G3, and -524H series, and RB211-535C and -
535E series turbofan engines with HPC stage 3 disc assemblies, P/Ns 
LK46210, LK58278, LK67634, LK76036, UL11706, UL15358, UL22577, UL22578, 
and UL24738 installed. The CAA advises that inspections at overhaul 
found many disc assemblies with corrosion-induced pitting. RR 
reassessed the risk of corrosion-induced pitting of disc assemblies 
that have not incorporated any revision of RR service bulletin (SB) No. 
RB.211-72-9434, or any revision of RR SB No. RB.211-72-5420, which 
rework the discs and apply anticorrosion protection, lowered the disc 
lives from those published in the Time Limits Manuals. These SBs rework 
the discs and apply anticorrosion protection, and lower the disc lives 
accordingly in the Time Limits Manuals.

Actions Since AD 04-01-20 Was Issued

    Since we issued that AD, we found that we made an oversight in the 
rule regarding the compliance time for disks that entered into service 
before 1990. We allowed operators to remove and rework these disks 
within five years after the effective date of that AD, but we intended 
to set a fixed calendar date based on inspection findings and 
metallurgical results. This proposed AD corrects that oversight. Also, 
we omitted paragraph (f)(5) from the original rule. We issued a 
correction to AD 04-01-20 on July 29, 2004, to include paragraph 
(f)(5). This proposed rule includes that paragraph.

Relevant Service Information

    We have reviewed and approved the technical contents of Rolls-Royce 
plc SB No. RB.211-72-9434, Revision 4, dated January 12, 2000, and SB 
No. RB.211-72-5420, Revision 4, dated February 29, 1980, which describe 
procedures for reworking of HPC stage 3 rotor disc assemblies by 
machining, and application of anticorrosion protection. The CAA, which 
is the airworthiness authority for the U.K., classified these SBs as 
mandatory and issued airworthiness directive 004-01-94, dated January 
4, 2002.

Bilateral Agreement Information

    This engine model is manufactured in the United Kingdom and is 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 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

[[Page 43660]]

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. We are proposing this AD, which would require 
the following for affected HPC stage 3 rotor disc assemblies:
     Removing affected disc assemblies from service.
     Re-machining, inspecting, and applying anticorrosion 
protection.
     Re-marking, and returning disc assemblies into service.
    The proposed AD would require that you do these actions using the 
service information described previously.

Costs of Compliance

    There are about 2,000 RR RB211-22B series, RB211-524B, -524C2, -
524D4, -524G2, -524G3, and -524H series, and RB211-535C and -535E 
series turbofan engines of the affected design in the worldwide fleet. 
We estimate that this proposed AD would affect 1,000 engines installed 
on airplanes of U.S. registry. We also estimate that it would take 
about 31 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 $38,000 per engine. Based on these figures, we estimate the 
total cost of the proposed AD to U.S. operators to be $40,015,000.

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 by 
sending a request to us at the address listed under ADDRESSES. Include 
``AD Docket No. 2003-NE-12-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 39-13434 (69 FR 
2661, January 20, 2004) and by adding a new airworthiness directive, to 
read as follows:

Rolls-Royce plc: Docket No. 2003-NE-12-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by September 
26, 2005.

Affected ADs

    (b) This AD supersedes AD 2004-01-20, Amendment 39-13434.

Applicability

    (c) This AD applies to Rolls-Royce plc (RR) RB211-22B series, 
RB211-524B, -4C2, -524D4, -524G2, -524G3, and -524H series, and 
RB211-535C and -535E series turbofan engines with high pressure 
compressor (HPC) stage 3 disc assemblies, part numbers (P/Ns) 
LK46210, LK58278, LK67634, LK76036, UL11706, UL15358, UL22577, 
UL22578, and UL24738 installed. These engines are installed on, but 
not limited to, Boeing 747, Boeing 757, Boeing 767, Lockheed L-1011, 
and Tupolev Tu204 series airplanes.

Unsafe Condition

    (d) This AD results from the manufacturer's reassessment of the 
corrosion risk on HPC stage 3 disc assemblies that have not yet been 
modified with sufficient application of anticorrosion protection. 
The actions specified in this AD are intended to prevent corrosion-
induced uncontained disc failure, resulting in 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.

Removal of HPC Stage 3 Discs

    (f) Remove from service affected HPC stage 3 disc assemblies 
identified in the following Table 1, using one of the following 
criteria:

[[Page 43661]]



                                 Table 1.--Affected HPC Stage 3 Disc Assemblies
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                                                                                                Rework band for
                                                        Rework band for                           cyclic life
                                                          cyclic life       Rework band for    accumulated on P/
                                                        accumulated on        cyclic life         Ns LK76036,
                                                      disc  assemblies P/   accumulated on     UL11706, UL15358,
                    Engine model                        Ns LK46210 and    disc  assembly P/N   UL22577, UL22578,
                                                       LK58278  (Pre RR    LK67634  (Pre RR    and UL24738 disc
                                                       service bulletin   SB  No. RB.211-72-  assemblies (Pre RR
                                                      (SB) No. RB.211-72-        5420)         SB No. RB.211-72-
                                                             5420)                                   9434)
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-22B series.........................................         4,000-6,200        7,000-10,000       11,500-14,000
-535E4 series.......................................                 N/A                 N/A        9,000-15,000
-524B-02, B-B-02, B3-02, and B4 series, Pre and SB           4,000-6,000         7,000-9,000       11,500-14,000
 No. 72-7730........................................
-524B2 and C2 series, Pre SB No. 72-7730............         4,000-6,000         7,000-9,000       11,500-14,000
-524B2-B-19 and C2-B-19, SB No. 72-7730.............         4,000-6,000         7,000-9,000        8,500-11,000
-524D4 series, Pre SB No. 72-7730...................         4,000-6,000         7,000-9,000       11,500-14,000
-524D4-B series, SB No. 72-7730.....................         4,000-6,000         7,000-9,000        8,500-11,000
-524G2, G3, H, and H2 series........................         4,000-6,000         7,000-9,000        8,500-11,000
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    (1) For discs that entered into service before 1990, remove disc 
and rework as specified in paragraph (g)(2) of this AD, on or before 
January 4, 2007, but not to exceed the upper cyclic limit in Table 1 
of this AD before rework. Discs reworked may not exceed the 
manufacturer's published cyclic limit in the time limits section of 
the manual.
    (2) For discs that entered into service in 1990 or later, remove 
disc within the cyclic life rework bands in Table 1 of this AD, or 
within 17 years after the date of the disc assembly entering into 
service, whichever is sooner, but not to exceed the upper cyclic 
limit of Table 1 of this AD before rework. Discs reworked may not 
exceed the manufacturer's published cyclic limit in the time limits 
section of the manual.
    (3) For disc assemblies that when new, were modified with an 
application of anticorrosion protection and re-marked to P/N LK76036 
(not previously machined) as specified by Part 1 of the original 
issue of RR service bulletin (SB) No. RB.211-72-5420, dated April 
20, 1979, remove RB211-22B disc assemblies before accumulating 
10,000 cycles-in-service (CIS), and remove RB211-524 disc assemblies 
before accumulating 9,000 CIS.
    (4) If the disc assembly date of entry into service cannot be 
determined, the date of disc manufacture may be obtained from RR and 
used instead.
    (5) Discs in RB211-535C operation are unaffected by the interim 
rework cyclic band limits in Table 1 of this AD, but must meet the 
calendar life requirements of either paragraph (f)(1) or (f)(2) of 
this AD, as applicable.

Optional Rework of HPC Stage 3 Discs

    (g) Rework HPC stage 3 disc assemblies that were removed in 
paragraph (f) of this AD as follows:
    (1) For disc assemblies that when new, were modified with an 
application of anticorrosion protection and re-marked to P/N LK76036 
(not previously machined) as specified by Part 1 of the original 
issue of RR SB RB.211-72-5420, dated April 20, 1979, rework disc 
assemblies and re-mark to either LK76034 or LK78814 using paragraph 
2.B. of the Accomplishment Instructions of RR SB No. RB.211-72-5420, 
Revision 4, dated February 29, 1980. This rework constitutes 
terminating action to the removal requirements in paragraph (f) of 
this AD.
    (2) For all other disc assemblies, rework using Paragraph 3.B. 
of the Accomplishment Instructions of RR SB No. RB.211-72-9434, 
Revision 4, dated January 12, 2000. This rework constitutes 
terminating action to the removal requirements in paragraph (f) of 
this AD.

    Note 1: If rework is done on disc assemblies that are removed 
before the disc assembly reaches the lower life of the cyclic life 
rework band in Table 1 of this AD, artificial aging of the disc to 
the lower life of the rework band, at time of rework, is required.

Alternative Methods of Compliance

    (h) 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

    (i) Civil Aviation Authority airworthiness directive 004-01-94, 
dated January 4, 2002, and RR Mandatory Service Bulletin No. RB.211-
72-9661, Revision 4, dated January 4, 2002, pertain to the subject 
of this AD.

    Issued in Burlington, Massachusetts, on July 21, 2005.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 05-14803 Filed 7-27-05; 8:45 am]
BILLING CODE 4910-13-P