Document ID: FAA-2012-1202-0004
Agency: faa
Document Type: Proposed Rule
Title: Airworthiness Directives: Rolls-Royce Deutschland Ltd and Co KG (Formerly Rolls-Royce Deutschland GmbH, Formerly BMW Rolls-Royce GmbH) Turbofan Engines
Posted Date: 2013-11-19T05:00Z

[Federal Register Volume 78, Number 223 (Tuesday, November 19, 2013)]
[Proposed Rules]
[Pages 69316-69318]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2013-27633]

 ========================================================================
 Proposed Rules
                                                 Federal Register
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 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.
 
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  Federal Register / Vol. 78, No. 223 / Tuesday, November 19, 2013 / 
Proposed Rules  

[[Page 69316]]

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-1202; Directorate Identifier 2012-NE-38-AD]
RIN 2120-AA64

Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG 
(Formerly Rolls-Royce Deutschland GmbH, Formerly BMW Rolls-Royce GmbH) 
Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: We propose to supersede existing airworthiness directive (AD) 
2012-26-14 that applies to all Rolls-Royce Deutschland Ltd & Co KG 
(RRD) BR700-715A1-30, BR700-715B1-30, and BR700-715C1-30 turbofan 
engines. AD 2012-26-14 currently requires removal from service of the 
high-pressure (HP) compressor stages 1 to 6 rotor disc assembly before 
exceeding certain thresholds. Since we issued AD 2012-26-14, RRD 
developed a new silver-free nut that, if installed with a new HP 
compressor stages 1 to 6 disc assembly, would correct the unsafe 
condition identified in AD 2012-26-14. Therefore, we propose to 
supersede AD 2012-26-14 to restrict the applicability to engines 
exposed to silver plated nuts. Additionally, we are removing the 
terminating action statement from AD 2012-26-14 based on a comment 
received. This proposed AD would require removal from service of 
certain HP compressor stages 1 to 6 rotor disc assemblies before 
exceeding certain thresholds. We are proposing this AD to prevent 
failure of the HP compressor stages 1 to 6 rotor disc assembly, which 
could lead to an uncontained engine failure and damage to the airplane.

DATES: We must receive comments on this proposed AD by January 21, 
2014.

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 AD, contact Rolls-Royce 
Deutschland Ltd & Co KG, Eschenweg 11, Dahlewitz, 15827 Blankenfelde-
Mahlow, Germany; phone: 49 0 33-7086-1200; fax: 49 0 33-7086-1212. You 
may view this service information at the FAA, Engine & Propeller 
Directorate, 12 New England Executive Park, Burlington, MA. For 
information on the availability of this material at the FAA, call 781-
238-7125.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Management Facility 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the MCAI, the 
regulatory evaluation, any comments received, and other information. 
The street address for the Docket Office (phone: 800-647-5527) is in 
the ADDRESSES section. Comments will be available in the AD docket 
shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Robert Morlath, Aerospace Engineer, 
Engine Certification Office, FAA, Engine & Propeller Directorate, 12 
New England Executive Park, Burlington, MA 01803; phone: 781-238 7154; 
fax: 781-238 7199; email: robert.c.morlath@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-2012-1202; 
Directorate Identifier 2012-NE-38-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD 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

    On December 27, 2012, we issued AD-2012-26-14, Amendment 39-17309 
(78 FR 2195, January 10, 2013) (``AD 2012-26-14'') for RRD BR700-715A1-
30, BR700-715B1-30, and BR700-715C1-30 turbofan engines. AD 2012-26-14 
requires removal from service of the HP compressor stages 1 to 6 rotor 
disc assembly before exceeding certain thresholds. AD 2012-26-14 
resulted from a report of silver chloride-induced stress corrosion 
cracking of the HP compressor stages 1 to 6 rotor disc assembly, 
identified during overhaul. We issued AD 2012-26-14 to prevent failure 
of the HP compressor stages 1 to 6 rotor disc assembly, which could 
lead to an uncontained engine failure and damage to the airplane. We 
set a separate compliance standard for engines operated under the 
Hawaiian Flight Mission. The different cycle limits are established 
because the Hawaiian Flight Mission profile was sufficiently different 
from the normal flight profile as to affect the cyclic loading on the 
life limited parts.

Actions Since Existing AD Was Issued

    Since we issued AD 2012-26-14, RRD released new part number (P/N) 
components as a design fix for the issue described above.
    We gave the public the opportunity to comment on AD 2012-26-14. We 
received two comments. The following presents the comments received, 
and the FAA's response to each comment.

Comments

Request To Include HP Compressor P/Ns in the AD

    Southwest Airlines (SWA) requested that we include the P/Ns of the 
affected HP compressor stages 1 to 6 rotor disc

[[Page 69317]]

assemblies in this AD. The commenter provided no justification for this 
request.
    We partially agree. We agree with revising the Applicability 
paragraph of this proposed AD because RRD developed new P/N silver-free 
nuts, which, if installed with a new HP compressor stages 1 to 6 rotor 
disc assembly, would correct the unsafe condition.
    We disagree with identifying specific HP compressor stages 1 to 6 
rotor disc assemblies because this proposed AD applies to all HP 
compressor stages 1 to 6 rotor disc assemblies that have had silver-
plated nuts installed. We revised the Applicability paragraph to 
clarify that this proposed AD applies to all HP compressor stages 1 to 
6 rotor disc assemblies that were installed using nuts, P/N AS44862 or 
P/N AS64367.

Request To Clarify Parts Eligible for Installation

    SWA requested that we clarify paragraph (f) of AD 2012-26-14. The 
commenter stated that it is unclear if reinstalling disc assemblies 
having fewer cycles since new (CSN) than that required by paragraph (e) 
of AD 2012-26-14, is acceptable.
    We agree. The intent of AD 2012-26-14 is to allow operation of the 
disc assembly up to the CSN specified in paragraph (e) of AD 2012-26-
14. It is acceptable to reinstall disc assemblies that have fewer CSN 
than specified in paragraph (e) of AD 2012-26-14. Therefore, we removed 
the terminating action paragraph from this proposed AD.

Conclusion

    We reviewed the relevant data and considered the comments received.

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 certain requirements of AD 2012-26-
14. This proposed AD would change the Applicability paragraph to 
specify the P/N nuts associated with reduced life and would also change 
paragraph (f) by removing language concerning the terminating action. 
This AD requires removal from service of certain HP compressor stages 1 
to 6 rotor disc assemblies before exceeding certain thresholds.

Costs of Compliance

    We estimate that this proposed AD would affect about 255 engines 
installed on airplanes of U.S. registry. We also estimate that it would 
take about 20 hours per engine to comply with this proposed AD. The 
average labor rate is $85 per hour. Prorated parts life will cost about 
$13,500 per engine. Based on these figures, we estimate the cost of 
this proposed AD on U.S. operators to be $3,876,000.

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 proposed 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),
    (3) Will not affect intrastate aviation in Alaska to the extent 
that it justifies making a regulatory distinction, 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) 
2012-26-14, Amendment 39-17309 (78 FR 2195, January 10, 2013), and 
adding the following new AD:

Rolls-Royce Deutschland Ltd & Co KG: Docket No. FAA-2012-1202; 
Directorate Identifier 2012-NE-38-AD.

(a) Comments Due Date

    The FAA must receive comments on this AD action by January 21, 
2014.

(b) Affected ADs

    This AD supersedes AD 2012-26-14, Amendment 39-17309 (78 FR 
2195, January 10, 2013).

(c) Applicability

    This AD applies to all Rolls-Royce Deutschland Ltd & Co KG (RRD) 
BR700-715A1-30, BR700-715B1-30, and BR700-715C1-30 turbofan engines 
with high-pressure (HP) compressor stages 1 to 6 rotor disc 
assemblies that were ever installed using nuts, part number (P/N) 
AS44862 or P/N AS64367.

(d) Unsafe Condition

    This AD was prompted by a report of silver chloride-induced 
stress corrosion cracking of the HP compressor stages 1 to 6 rotor 
disc assembly. We are issuing this AD to prevent failure of the HP 
compressor stages 1 to 6 rotor disc assembly, which could lead to an 
uncontained engine failure and damage to the airplane.

(e) Compliance

    Comply with this AD within the compliance times specified, 
unless already done.
    (1) For BR700-715A1-30 turbofan engines operated under the 
Hawaiian Flight Mission only, remove the HP compressor stages 1 to 6 
rotor disc assembly from service before exceeding 16,000 flight 
cycles since new (CSN) or before further flight after the effective 
date of this AD, whichever occurs later.
    (2) For BR700-715A1-30, BR700-715B1-30, and BR700-715C1-30 
turbofan engines (all flight missions except Hawaiian Flight 
Mission), remove the HP compressor stages 1 to 6 rotor disc assembly 
from service before

[[Page 69318]]

exceeding 14,000 flight CSN or before further flight after the 
effective date of this AD, whichever occurs later.

(f) Prohibition Statement

    After the effective date of this AD, do not install an HP 
compressor stages 1 to 6 rotor disk assembly into an engine, or an 
engine with an HP compressor stage 1 to 6 rotor disk assembly onto 
an aircraft, if the HP compressor stages 1 to 6 rotor disk assembly 
has ever been operated with nuts, P/N AS44862 or P/N AS64367, and 
has more CSN than specified in the applicable portion of the 
compliance section of this AD.

(g) Definition

    For the purpose of this AD, flight cycles is defined as the 
total flight CSN on the HP compressor stages 1 to 6 rotor disc 
assembly, without any pro-rated calculations applied for different 
flight missions.

(h) Alternative Methods of Compliance (AMOCs)

    The Manager, Engine Certification Office, may approve AMOCs for 
this AD. Use the procedures found in 14 CFR 39.19, to make your 
request.

(i) Related Information

    (1) For more information about this AD, contact Robert Morlath, 
Aerospace Engineer, Engine Certification Office, FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, MA 
01803; phone: 781-238 7154; fax: 781-238 7199; email: 
robert.c.morlath@faa.gov.
    (2) Refer to MCAI European Aviation Safety Agency AD 2012-0230, 
dated October 30, 2012. You may examine this MCAI in the AD docket 
on the Internet at http://www.regulations.gov/#!documentDetail;D=FAA-2012-1202-0003.
    (3) For service information identified in this AD, contact 
Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, Dahlewitz, 15827 
Blankenfelde-Mahlow, Germany; phone: 49 0 33-7086-1200; fax: 49 0 
33-7086-1212.
    (4) You may view this service information at the FAA, Engine & 
Propeller Directorate, 12 New England Executive Park, Burlington, 
MA. For information on the availability of this material at the FAA, 
call 781-238-7125.

    Issued in Burlington, Massachusetts, on November 8, 2013.
Colleen M. D'Alessandro,
Assistant Directorate Manager, Engine & Propeller Directorate, Aircraft 
Certification Service.

[FR Doc. 2013-27633 Filed 11-18-13; 8:45 am]
BILLING CODE 4910-13-P