Document ID: FAA-2018-1034-0001
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Rolls-Royce plc Turbofan Engines
Posted Date: 2019-05-20T04:00Z

[Federal Register Volume 84, Number 97 (Monday, May 20, 2019)]
[Proposed Rules]
[Pages 22738-22740]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2019-10233]

 ========================================================================
 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.
 
 ========================================================================
 

  Federal Register / Vol. 84, No. 97 / Monday, May 20, 2019 / Proposed 
Rules  

[[Page 22738]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2018-1034; Product Identifier 2018-NE-38-AD]
RIN 2120-AA64

Airworthiness Directives; Rolls-Royce plc Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to supersede airworthiness directive (AD) 2008-22-
24 which applies to certain Rolls-Royce plc (RR) RB211-535E4-37, RB211-
535E4-B-37, and RB211-535E4-B-75 model turbofan engines. AD 2008-22-24 
requires initial and repetitive ultrasonic inspections of installed 
low-pressure compressor (LPC) fan blade roots on-wing and during 
overhaul, and relubrication according to accumulated life cycles. Since 
we issued AD 2008-22-24, RR determined the need to expand the 
inspections to engines operating under additional flight profiles and 
to extend the inspection intervals for certain affected engines. This 
proposed AD would require initial and repetitive inspections to detect 
cracks on the installed LPC fan blade roots on-wing or at engine 
overhaul. We are proposing this AD to address the unsafe condition on 
these products.

DATES: We must receive comments on this proposed AD by July 1, 2019.

ADDRESSES: You may send comments, using the procedures found in 14 CFR 
11.43 and 11.45, by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: 202-493-2251.
     Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE, Washington, DC 20590.
     Hand Delivery: Deliver to Mail address above between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this NPRM, contact, Rolls-
Royce plc, Corporate Communications, P.O. Box 31, Derby, England, DE24 
8BJ; phone: 011-44-1332-242424; fax: 011-44-1332-249936; email: http://www.rolls-royce.com/contact/civil_team.jsp; internet: https://www.aeromanager.com. You may view this service information at the FAA, 
Engine & Propeller Standards Branch, 1200 District Avenue, Burlington, 
MA 01803. For information on the availability of this material at the 
FAA, call 781-238-7759.

Examining the AD Docket

    You may examine the AD docket on the internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2018-
1034; or in person at Docket Operations between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays. The AD docket contains 
this NPRM, the mandatory continuing airworthiness information, the 
regulatory evaluation, any comments received, and other information. 
The street address for Docket Operations (phone: 800-647-5527) is 
listed above. Comments will be available in the AD docket shortly after 
receipt.

FOR FURTHER INFORMATION CONTACT: Matthew Smith, Aerospace Engineer, ECO 
Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone: 781-
238-7735; fax: 781-238-7199; email: mathew.c.smith@faa.gov.

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2018-1034; 
Product Identifier 2018-NE-38-AD'' at the beginning of your comments. 
We specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of this NPRM. We will consider all 
comments received by the closing date and may amend this NPRM because 
of those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    We issued AD 2008-22-24, Amendment 39-15721 (73 FR 65511, November 
4, 2008), (``AD 2008-22-24''), for certain RR RB211-535E4-37, RB211-
535E4-B-37, and RB211-535E4-B-75 model turbofan engines. AD 2008-22-24 
requires initial and repetitive ultrasonic inspections of installed LPC 
fan blade roots on-wing and during overhaul, and relubrication 
according to accumulated life cycles. AD 2008-22-24 resulted from the 
discovery of cracks in LPC fan blade roots. We issued AD 2008-22-24 to 
detect cracks in LPC fan blade roots, which if not detected, could lead 
to uncontained multiple fan blade failure and damage to the airplane.

Actions Since AD 2008-22-24 Was Issued

    Since we issued AD 2008-22-24, it was reported that some engines 
were operated outside the profiles initially specified, and RR 
introduced new flight profiles to mitigate the risk of overflying the 
recommended flight profiles. Consequently, RR extended the inspection 
intervals for engines operating within RB211-535E4-B-37 flight profiles 
C, D and E. Additionally, RR introduced inspection instructions for 
engines operating within RB211-535E4-C-37 flight profile F and RB211-
535E4-37 flight profile G. Also since we issued AD 2008-22-24, the 
European Union Aviation Safety Agency (EASA) has issued AD 2018-0202R1, 
dated September 25, 2018, which requires initial and repetitive 
ultrasonic inspections of installed LPC fan blade roots.

Related Service Information Under 1 CFR Part 51

    We reviewed Rolls-Royce Alert Non-Modification Service Bulletin 
(NMSB) No. RB.211-72-AC879, Revision 9, dated April 23, 2018 and Rolls-
Royce Service Bulletin (SB) RB.211-72-C946, Revision 4, dated June 22, 
2010. Rolls-Royce NMSB RB.211-72-AC879 describes procedures for 
performing inspections of high cyclic life LPC fan

[[Page 22739]]

blade roots on-wing or at overhaul, and re-lubrication of the LPC fan 
blade roots during overhaul. Rolls-Royce SB RB.211-72-C946 introduces a 
revised LPC fan blade featuring a redefined dry film lubricant 
application. This service information is reasonably available because 
the interested parties have access to it through their normal course of 
business or by the means identified in the ADDRESSES section.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Proposed AD Requirements

    This proposed AD would retain the requirements of AD 2008-22-24. 
The proposed AD would extend these requirements to engines operating 
under additional flight profiles and add the RB211-535E4-C-37 model 
turbofan engines to the applicability of this AD. This proposed AD 
would require initial and repetitive inspections of LPC fan blade roots 
on-wing or at engine overhaul, and replacement of blades that exceed 
the criteria in the Rolls-Royce Alert NMSB RB211-72-AC879, Revision 9, 
dated April 23, 2018.

Costs of Compliance

    We estimate that this proposed AD affects 512 engines installed on 
airplanes of U.S. registry.
    We estimate the following costs to comply with this proposed AD:

                                                 Estimated costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
                Action                         Labor cost           Parts cost        product        operators
----------------------------------------------------------------------------------------------------------------
Inspection of LPC fan blade set.......  7 workhours x $85 per                 $0            $595        $304,640
                                         hour = $595.
----------------------------------------------------------------------------------------------------------------

    We estimate the following costs to do any necessary replacements 
that would be required based on the results of the proposed inspection. 
We have no way of determining the number of aircraft that might need 
these replacements:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                   Action                                 Labor cost                Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replacement of LPC fan blade...............  4 work-hours x $85 per hour = $340.         $77,916         $78,256
----------------------------------------------------------------------------------------------------------------

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.
    This AD is issued in accordance with authority delegated by the 
Executive Director, Aircraft Certification Service, as authorized by 
FAA Order 8000.51C. In accordance with that order, issuance of ADs is 
normally a function of the Compliance and Airworthiness Division, but 
during this transition period, the Executive Director has delegated the 
authority to issue ADs applicable to engines, propellers, and 
associated appliances to the Manager, Engine and Propeller Standards 
Branch, Policy and Innovation Division.

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),
    (3) Will not affect intrastate aviation in Alaska, and
    (4) 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.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
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]

0
2. The FAA amends Sec.  39.13 by removing airworthiness directive (AD) 
2008-22-24, Amendment 39-15721 (73 FR 65511, November 4, 2008), and 
adding the following new AD:

Rolls-Royce plc: Docket No. FAA-2018-1034; Product Identifier 2018-
NE-38-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by July 1, 2019.

(b) Affected ADs

    This AD replaces AD 2008-22-24, Amendment 39-15721 (73 FR 65511, 
November 4, 2008).

[[Page 22740]]

(c) Applicability

    This AD applies to Rolls-Royce plc (RR) RB211-535E4-37, RB211-
535E4-B-37, RB211-535E4-C-37, and RB-211-535E4-B-75 model turbofan 
engines except those with fan blades that have all incorporated 
Rolls-Royce Service Bulletin (SB) RB.211-72-C946, Revision 4, dated 
June 22, 2010 (or any earlier revision).

(d) Subject

    Joint Aircraft System Component (JASC) Code 7230, Turbine Engine 
Compressor Section.

(e) Unsafe Condition

    This AD was prompted by small cracks found in the low-pressure 
compressor (LPC) fan blade roots on the conclave root flank during 
an engine overhaul. We are issuing this AD to detect cracks in the 
LPC fan blade roots. The unsafe condition, if not addressed, could 
result in uncontained LPC fan blade release, damage to the engine, 
and damage to the airplane.

(f) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Required Actions

    (1) For engine models being used in the flight profiles 
indicated in Table 1 to paragraph (g)(1) of this AD, perform initial 
and repetitive ultrasonic inspections of the affected fan blades in 
accordance with the Accomplishment Instructions, paragraphs 3.A., 
3.B., and 3.C., of Rolls-Royce Alert Non-Modification Service 
Bulletin (NMSB) RB211-72-AC879, Revision 9, dated April 23, 2018, as 
follows:
    (i) Perform an initial ultrasonic root or surface wave 
inspection of each LPC fan blade before exceeding the inspection 
threshold as indicated in Table 1 to paragraph (g)(1) of this AD, or 
within 30 days after the effective date of this AD, whichever occurs 
later.
    (ii) Thereafter, perform a repetitive ultrasonic root or surface 
wave inspection of each LPC fan blade at intervals not to exceed 
engine flight cycles (EFCs) since the previous inspection using the 
applicable EFCs specified in Table 1 to paragraph (g)(1) of this AD.

                        Table 1 to Paragraph (g)(1)--Flight Profile Inspection Intervals
----------------------------------------------------------------------------------------------------------------
                                                      Initial inspection     Reinspection        Reinspection
              Model                 Flight profile      threshold, EFCs     interval; root     interval; surface
                                                           since new         probe method      wave probe method
----------------------------------------------------------------------------------------------------------------
535 E4-37.......................  B and G...........  15,000 EFCs.......  850 EFCs..........  700 EFCs.
535E4-C-37......................  F.................  15,000 EFCs.......  850 EFCs..........  700 EFCs.
535E4-B-37......................  E and C...........  20,000 EFCs.......  1,200 EFCs........  1,000 EFCs.
535E4-B-75......................  All...............  20,000 EFCs.......  1,200 EFCs........  1,000 EFCs.
535E4-37........................  A.................  20,000 EFCs.......  1,400 EFCs........  1,150 EFCs.
535E4-B-37......................  D.................  20,000 EFCs.......  1,500 EFCs........  1,200 EFCs.
----------------------------------------------------------------------------------------------------------------

    (2) For engine models that, after the effective date of this AD, 
change flight profiles, inspect the affected fan blades before 
exceeding the initial threshold of the new flight profile or 
reinspection interval, as applicable, or within 200 EFCs after 
changing flight profiles, whichever occurs later, without exceeding 
the previous flight profile initial inspection threshold or 
reinspection interval.
    (3) If, during any inspection required by paragraph (g)(1) or 
(2) of this AD, any crack is found in the affected fan blades that 
exceeds the criteria in the Accomplishment Instructions, paragraphs 
3.A., 3.B., or 3.C., of Rolls-Royce Alert NMSB RB211-72-AC879, 
Revision 9, dated April 23, 2018, before the next flight, replace 
the LPC fan blade with a LPC fan blade eligible for installation.

(h) Optional Terminating Action

    Modification of any RR RB211-535E4-37, RB211-535E4-B-37, RB211-
535E4-C-37, and RB-211-535E4-B-75 model turbofan engine in 
accordance with Rolls-Royce SB RB.211-72-C946, Revision 4, dated 
June 22, 2010, constitutes terminating action to this AD.

(i) Credit for Previous Actions

    Any initial ultrasonic inspection accomplished before the 
effective date of this AD that uses Rolls-Royce NMSB No. RB.211-72-
C879, Revision 8, dated November 18, 2015, or earlier versions, 
meets the requirement of the initial inspection, as applicable. Any 
repetitive ultrasonic inspection accomplished before the effective 
date of this AD that uses RR NMSB No. RB.211-72-C879, Revision 8, 
dated November 18, 2015, or earlier versions, meets the requirement 
of that single repetitive inspection, as applicable. Further 
repetitive inspections, as mandated by paragraph (g) of this AD, are 
still required.

(j) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, ECO Branch, FAA, has the authority to approve 
AMOCs for this AD, if requested using the procedures found in 14 CFR 
39.19. In accordance with 14 CFR 39.19, send your request to your 
principal inspector or local Flight Standards District Office, as 
appropriate. If sending information directly to the manager of the 
ECO Branch, send it to the attention of the person identified in 
paragraph (k)(1) of this AD. You may email your request to: ANE-AD-AMOC@faa.gov.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.

(k) Related Information

    (1) For more information about this AD, contact Matthew Smith, 
Aerospace Engineer, ECO Branch, FAA, 1200 District Avenue, 
Burlington, MA 01803; phone: 781-238-7735; fax: 781-238-7199; email: 
matthew.c.smith@faa.gov.
    (2) Refer to European Union Aviation Safety Agency (EASA) AD 
2018-0202R1, dated September 25, 2018, for more information. You may 
examine the EASA AD in the AD docket on the internet at http://www.regulations.gov by searching for and locating it in Docket No. 
FAA-2018-1034.
    (3) For RR service information identified in this AD, contact 
Rolls-Royce plc, PO Box 31, Derby, England, DE248BJ; telephone: 011-
44-1332-242424; fax: 011-44-1332-249936. You may view this 
referenced service information at the FAA, Engine & Propeller 
Standards Branch, 1200 District Avenue, Burlington, MA 01803. For 
information on the availability of this material at the FAA, call 
781-238-7759.

    Issued in Burlington, Massachusetts, on May 13, 2019.
Robert J. Ganley,
Manager, Engine & Propeller Standards Branch, Aircraft Certification 
Service.
[FR Doc. 2019-10233 Filed 5-17-19; 8:45 am]
 BILLING CODE 4910-13-P