[Federal Register Volume 70, Number 21 (Wednesday, February 2, 2005)]
[Proposed Rules]
[Pages 5390-5393]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-1799]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NE-40-AD]
RIN 2120-AA64


Airworthiness Directives; Rolls-Royce plc RB211-524 Series 
Turbofan Engines

AGENCY: Federal Aviation Administration, DOT.

ACTION: Supplemental notice of proposed rulemaking; reopening of 
comment period.

-----------------------------------------------------------------------

SUMMARY: This notice revises an earlier proposed airworthiness 
directive (AD), applicable to Rolls Royce plc (RR) RB211-524 series 
turbofan engines with certain part number (P/N) intermediate pressure 
(IP) compressor stage 5 disks installed. That proposal required new 
reduced IP compressor stage 5 disk cyclic limits. That proposal also 
required removing from service affected disks that already exceed the 
new reduced cyclic limit, and removing other affected disks before 
exceeding their cyclic limits, using a drawdown schedule. That proposal 
resulted from the discovery of cracks in the cooling air hole areas of 
the disk front spacer arm. This Supplemental Notice of Proposed 
Rulemaking (SNPRM) revises the proposed rule by correcting certain 
cycle life limits specified in Table 3 of that AD and by clarifying 
certain inspections. We are proposing this AD to prevent IP compressor 
stage 5 disk failure, which could result in uncontained engine failure 
and possible damage to the airplane.

DATES: Comments must be received by April 4, 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. 2002-NE-40-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, DE248BJ, 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. 2002-NE-40-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 October 21, 2003 we issued a proposal to amend part 39 of the 
Federal Aviation Regulations (14 CFR part 39) to add an AD to apply to 
RR RB211-524 series turbofan engines, with certain P/N IP compressor 
stage 5 disks installed. The Office of the Federal Register published 
that proposal as a notice of proposed rulemaking (NPRM) in the Federal 
Register on October 27, 2003 (68 FR 61158). That NPRM would have 
required new reduced IP compressor stage 5 disk cyclic limits. The NPRM 
also required removing from service affected disks that already exceed 
the new reduced cyclic limit, and removing other affected disks before 
exceeding their cyclic limits, using a drawdown schedule. That NPRM 
resulted from the discovery of cracks in the cooling air hole areas of 
the disk front spacer arm. That condition, if not corrected, could 
result in IP compressor stage 5 disk failure, which could result in 
uncontained engine failure and possible damage to the airplane.
    Since we issued that NPRM, we found an error in Table 3 at the date 
December 1, 2008 row. The cycle life limits in columns 4 and 5 of this 
row were written incorrectly as 12,000. We have corrected those cycle 
life limits to 8,900 and 9,000 CIS, respectively. We have removed the 
phrase ``one-time'' in reference to on-wing inspections. We also added 
a sentence to clarify that an on-wing inspection may be used to extend 
service life only once between shop visit inspections of the disk.
    Since these changes expand the scope of the originally proposed 
rule, we determined that it is necessary to reopen the comment period 
to provide additional opportunity for public comment.

Manufacturer's Service Information

    We have reviewed and approved the technical contents of RR 
Mandatory Service Bulletin (MSB) No. RB.211-72-D428, Revision 3, dated 
June 30, 2003, that specifies a drawdown schedule for

[[Page 5391]]

removing from service affected IP compressor stage 5 disks, using new 
RR Time Limits Manual (TLM), 05-10-01 cyclic limits. The MSB also 
describes procedures for optional inspections at each shop visit to 
extend the disk life beyond the lives specified. The Civil Aviation 
Authority (CAA), the airworthiness authority of the United Kingdom 
(U.K.), has classified this service bulletin as mandatory and issued AD 
006-04-2002 to ensure the airworthiness of these RR turbofan engines in 
the U.K. We have also reviewed and approved the technical contents of 
Service Bulletin (SB) No. RB.211-72-E148, dated March 13, 2003 and SB 
No. RB.211-72-E150, Revision 1, dated June 4, 2003, that provide an 
optional on-wing ECI of the affected disks, to extend the disk life 
beyond the lives specified.

Differences Between This Proposed AD and the Manufacturer's Service 
Information

    This proposed AD adds a requirement to change the service cyclic 
limits in the Time Limits Manual and to remove or inspect disks not 
later than 30 days after the effective date of this AD.

FAA's Determination of an Unsafe Condition and Proposed Actions

    These engine models, 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. Under this bilateral 
airworthiness agreement, the CAA has 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. Therefore, we are proposing this AD, which would 
require:
     Establishing new reduced IP compressor stage 5 disk cyclic 
limits.
     Removing from service affected disks that already exceed 
the new reduced cyclic limit.
     Removing other affected disks before exceeding their 
cyclic limits, using a drawdown schedule.
     Allowing optional inspections at each shop visit or an on-
wing ECI to extend the disk life beyond the specified life.

The proposed AD would require you to use the service information 
described previously to perform these actions.

Economic Analysis

    There are about 939 RR RB211-524 series turbofan engines of the 
affected design in the worldwide fleet. We estimate that 35 engines 
installed on airplanes of U.S. registry will be affected by this 
proposed AD. We also estimate that it will take about 8 work hours per 
engine to perform an inspection, and 300 work hours per engine to 
replace an IP compressor stage 5 disk. The average labor rate is $65 
per work hour. Required parts will cost about $49,000 per engine. Based 
on these figures, we estimate the total cost of the AD to U.S. 
operators to be $2,415,700.

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 Analysis

    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, Incorporation by 
reference, 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. Section 39.13 is amended by adding the following new 
airworthiness directive:

Rolls Royce plc: Docket No. 2002-NE-40-AD.

Comments Due Date

    (a) The Federal Aviation Administration (FAA) must receive 
comments on this airworthiness directive (AD) action by April 4, 
2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to the Rolls-Royce plc (RR) RB211-524 series 
turbofan engines listed in the following Table 1, with intermediate 
pressure (IP) compressor stage 5 disk part numbers (P/Ns) listed in 
Table 2 of this AD, installed.

                                        Table 1.--Engine Models Affected
----------------------------------------------------------------------------------------------------------------
 
----------------------------------------------------------------------------------------------------------------
-524B-02               -524B-B-02             -524B3-02              -524B4-02              -524B4-D-02
-524B2-19              -524B2-B-19            -524C2-19              -524C2-B-19            -524D4-19
-524D4-B-19            -524D4X-19             -524D4X-B-19           -524D4-39              -524D4-B-39
-524G2-19              -524G2-T-19            -524G3-19              -524G3-T-19            -524H2-19
-524H2-T-19            -524H-36               -524H-T-36             .....................  ....................
----------------------------------------------------------------------------------------------------------------

    These engines are installed on, but not limited to, Boeing 747, 
767, and Lockheed L-1011 airplanes.

[[Page 5392]]



                               Table 2.--IP Compressor Stage 5 Disk P/Ns Affected
----------------------------------------------------------------------------------------------------------------
 
----------------------------------------------------------------------------------------------------------------
LK60130                LK65932                LK69021                LK81269                LK83282
LK83283                UL12290                UL15743                UL15744                UL15745
UL19132                UL20785                UL20832                UL23291                UL25011
UL36821                UL36977                UL36978                UL36979                UL36980
UL36981                UL36982                UL36983                UL37078                UL37079
UL37080                UL37081                UL37082                UL37083                UL37084
----------------------------------------------------------------------------------------------------------------

Unsafe Condition

    (d) This AD results from discovery of cracks in the cooling air 
hole areas of the disk front spacer arm. The actions specified in 
this AD are intended to prevent IP compressor stage 5 disk failure, 
which could result in uncontained engine failure and possible 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.

Cycle Limits

    (f) Change the service cyclic limits contained in the Time 
Limits Manual, 05-10-01, for the IP compressor stage 5 discs 
installed in the engine models listed in the following Table 3, 
within 30 days after the effective date of this AD.

                   Table 3.--Cyclic Life Limits Without Qualifying Magnetic Particle Inspection (MPI) Or Eddy Current Inspection (ECI)
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                       Engine Models
                                  ----------------------------------------------------------------------------------------------------------------------
    Date of reduced life limit      -524G2, G2-T, G3, G3-T, H2,   -524D4, D4-B, D4-B-39, D4X,                                -524B-02, B-B-02, B3-02, B4-
                                        H2-T, H-36, H-T-36               D4X-B, D4-39             -524B2, B2-B, C2, C2-B             02, B4-D-02
--------------------------------------------------------------------------------------------------------------------------------------------------------
November 30, 2002................  13,500 cycles-in-service      16,150 CIS                    16,000 CIS                    16,200 CIS
                                    (CIS)
April 1, 2003....................  13,500 CIS                    13,500 CIS                    13,500 CIS                    14,000 CIS
December 1, 2003.................  12,000 CIS                    13,500 CIS                    13,500 CIS                    14,000 CIS
December 1, 2004.................  11,000 CIS                    13,500 CIS                    12,000 CIS                    12,000 CIS
December 1, 2005.................  11,000 CIS                    12,000 CIS                    12,000 CIS                    12,000 CIS
December 1, 2008.................  7,830 CIS                     8,700 CIS                     8,900 CIS                     9,000 CIS
--------------------------------------------------------------------------------------------------------------------------------------------------------

Optional Inspections

    (g) Before December 1, 2008, optional inspections are allowed at 
each shop visit or on-wing to extend the disk life. Guidance for 
these inspections is provided in paragraphs (h) or (i) of this AD.

Optional Inspections at Shop Visit

    (h) Perform optional inspections at shop visit, as follows:
    (1) Remove corrosion protection from IP stage 5 disk. 
Information on corrosion protection removal can be found in the 
Engine Manual.
    (2) Visual-inspect and binocular-inspect the IP stage 5 disk for 
corrosion pitting at the cooling air holes and defender holes in the 
disk front spacer arm. Follow paragraph 3.C. of the Accomplishment 
Instructions of RR MSB No. RB.211-72-D428, Revision 3, dated June 
30, 2003. Information on disk corrosion pitting limits can be found 
in the Engine Manual.
    (i) If the disk has corrosion pitting in excess of limits, 
remove the disk from service.
    (ii) If the disk is free from corrosion pitting, MPI the entire 
disk. Information on MPI can be found in the Engine Manual. If the 
disk passes MPI and no cracks are found, complete all other 
inspections, re-apply corrosion protection to disk, and return the 
disk to service in accordance with the cyclic limits allowed by 
paragraph (k) of this AD. Information on MPI limits can be found in 
the Engine Manual. Information on re-applying corrosion protection 
can be found in RR Repair FRS5900.
    (iii) If the disk has corrosion pitting within limits, ECI all 
disk cooling air holes, defender holes, and inner and outer faces. 
Follow paragraph 3.D. of the Accomplishment Instructions of RR MSB 
No. RB.211-72-D428, Revision 3, dated June 30, 2003. Information on 
corrosion pitting limits can be found in the Engine Manual. If the 
disk passes ECI and no cracks are found, MPI the entire disk. 
Information on MPI can be found in the Engine Manual. If the disk 
passes MPI and no cracks are found, re-apply corrosion protection to 
disk, and return the disk to service in accordance with the cyclic 
limits allowed by paragraph (k) of this AD.

Optional On-Wing EC Inspections

    (i) For RB211-524B2/C2 and RB211-524B4/D4 engine models, an on-
wing ECI of the IP compressor stage 5 disk may be performed only 
once between shop visit inspections. Follow paragraphs 3.A. through 
3.F. of the Accomplishment Instructions of RR SB No. RB.211-72-E148, 
dated March 13, 2003, and RR SB No. RB.211-72-E150, Revision 1, 
dated June 4, 2003, respectively, to do the ECI. If the disk passes 
the ECI and no cracks are found, an extension is allowed as 
specified in paragraph (k) of this AD.

Definition of Shop Visit

    (j) For the purposes of this AD, a shop visit is defined as the 
separation of an engine major case flange. This definition excludes 
shop visits when only field maintenance type activities are 
performed in lieu of performing them on-wing. (i.e., for purposes 
such as to perform an on-wing inspection of a tail engine 
installation on a Lockheed L-1011 airplane).

Cyclic Life Extension

    (k) Disks that pass an optional inspection may remain in service 
after that inspection for the additional cycles listed in the 
following Table 4, until the next inspection, or December 1, 2008, 
or until the cyclic life limit published in the Time Limits Manual 
is reached, whichever occurs first.

                                                             Table 4.--Cyclic Life Extension
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                    -524G2, G2-T, G3, G3-T, H2,   -524D4, D4-B, D4-B-39, D4X,                                -524B-02, B-B-02, B3-02, B4-
          Engine models                 H2-T, H-36, H-T-36               D4X-B, D4-39             -524B2, B2-B, C2, C2-B             02, B4-D-02
--------------------------------------------------------------------------------------------------------------------------------------------------------
Extension After Passing MPI......  1,600 cycles                  2,000 cycles                  2,000 cycles                  2,000 cycles.

[[Page 5393]]

 
Extension After Passing In-Shop    3,800 cycles                  4,500 cycles                  4,500 cycles                  4,500 cycles.
 ECI.
Extension After Passing On-Wing    1,000 cycles                  1,200 cycles                  1,200 cycles                  1,200 cycles.
 ECI.
--------------------------------------------------------------------------------------------------------------------------------------------------------

Disks That Have Been Intermixed Between Engine Models

    (l) Information on intermixing disks between engine models can 
be found in the RR Time Limits Manual, 05-00-01.

Alternative Methods of Compliance

    (m) 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.

Credit for Previous Inspections

    (n) Inspections done using RR SB No. RB.211-72-E150, dated April 
17, 2003 are acceptable in meeting the requirements of this AD.

Reporting Requirement

    (o) Report findings of all inspections of the IP stage 5 disk 
using paragraph 3.B.(2) of the Accomplishment Instructions of RR ASB 
RB.211-72-D428, Revision 3, dated June 30, 2003. The Office of 
Management and Budget (OMB) has approved the reporting requirements 
specified in Paragraph 3.B. of the Accomplishment Instructions of RR 
ASB RB.211-72-D428, Revision 3, dated June 30, 2003, and assigned 
OMB control number 2120-0056.

Related Information

    (p) CAA airworthiness directive 006-04-2002, dated April 2002, 
also addresses the subject of this AD.

    Issued in Burlington, Massachusetts, on January 25, 2005.
Francis A. Favara,
Acting Manager, Engine and Propeller Directorate, Aircraft 
Certification Service.
[FR Doc. 05-1799 Filed 2-1-05; 8:45 am]
BILLING CODE 4910-13-P