Document ID: FAA-2012-1202-0006
Agency: faa
Document Type: Rule
Title: Airworthiness Directives: Rolls-Royce Deutschland Ltd and Co KG Turbofan Engines
Posted Date: 2014-04-03T04:00Z

[Federal Register Volume 79, Number 64 (Thursday, April 3, 2014)]
[Rules and Regulations]
[Pages 18629-18630]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2014-07444]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-1202; Directorate Identifier 2012-NE-38-AD; 
Amendment 39-17816; AD 2014-07-02]
RIN 2120-AA64

Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG 
Turbofan Engines

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: We are superseding airworthiness directive (AD) 2012-26-14 for 
all Rolls-Royce Deutschland Ltd & Co KG (RRD) BR700-715A1-30, BR700-
715B1-30, and BR700-715C1-30 turbofan engines. AD 2012-26-14 required 
removal from service of certain high-pressure (HP) compressor stages 1 
to 6 rotor disc assemblies before exceeding certain thresholds. This AD 
requires removal from service at those same thresholds but restricts 
the applicability to engines exposed to silver-plated nuts, and removes 
the terminating action statement required by AD 2012-26-14. This AD was 
prompted by RRD development of a new silver-free nut that, if installed 
with a new HP compressor stages 1 to 6 rotor disc assembly, would 
correct the unsafe condition identified in AD 2012-26-14. 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.

DATES: This AD is effective May 8, 2014.

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-2012-
1202; 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 AD, the mandatory continuing airworthiness information 
(MCAI), the regulatory evaluation, any comments received, and other 
information. The address for the Docket Office (phone: 800-647-5527) is 
Document Management Facility, U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue SE., Washington, DC 20590.

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:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to supersede AD 2012-26-14, Amendment 39-17309 (78 FR 2195, 
January 10, 2013), (``AD 2012-26-14''). AD 2012-26-14 applied to the 
specified products. The NPRM published in the Federal Register on 
November 19, 2013 (78 FR 69316). The NPRM proposed to continue to 
require removal from service of certain HP compressor stages 1 to 6 
rotor disc assemblies before exceeding certain thresholds. The NPRM 
also proposed to restrict the applicability to engines exposed to 
silver-plated nuts, and to remove the terminating action statement 
required by AD 2012-26-14.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We considered the comments received.

Request To Include a Mandatory Terminating Action

    RRD requested that we include the installation of a new HP 
compressor stages 1 to 6 rotor disc assembly with silver-free nuts, 
part number (P/N) U755872, as a necessary terminating action to the 
parts removal requirements of this AD, because this would eliminate the 
unsafe condition caused by silver nut corrosion.
    We disagree. The flight cycle limits imposed by this AD on engines 
operating with silver-plated nuts provide an acceptable level of 
safety. Requiring operators to purchase a new HP compressor stages 1 to 
6 rotor disc assembly and new silver-free nuts would be an undue 
economic burden. If an operator chooses to install a new HP compressor 
stages 1 to 6 rotor disc assembly and silver-free nuts, P/N U755872, 
this AD would no longer apply to that engine. We did not change this 
AD.

Request To Require the Replacement of Affected P/Ns at Listed Intervals

    RRD requested that instead of requiring a one-time replacement of 
the HP compressor stages 1 to 6 rotor disc assembly installed with 
silver-plated nuts, we require replacement of the P/Ns at intervals 
published in European Aviation Safety Agency (EASA) AD 2012-0230, 
Initial Issue, dated October 30, 2012.
    We disagree. Our proposed AD did not require a one-time 
replacement. This AD requires, for any HP compressor stages 1 to 6 
rotor disc assembly that has ever been installed with silver-plated 
nuts, replacement at the cyclic limits stated in paragraphs (e)(1) and 
(e)(2) of this AD, which are equivalent to the cyclic limits stated in 
EASA AD 2012-0230, Initial Issue, dated October 30, 2012. We did not 
change this AD.

Request To Update Service Information References to the Most Recent 
Versions

    RRD requested that we update references to service bulletins (SBs) 
to the most recent versions.
    We disagree. We do not reference any SBs in this AD. We did not 
change this AD.

Conclusion

    We reviewed the available data, including the comments received, 
and determined that air safety and the public interest require adopting 
the AD as proposed.

Costs of Compliance

    We estimate that this AD affects 255 engines installed on airplanes 
of U.S. registry. We also estimate that it will take about 20 hours per 
engine to comply with this 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 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

[[Page 18630]]

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

    This AD will not have federalism implications under Executive Order 
13132. This AD will 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 this AD:
    (1) Is not a ``significant regulatory action'' under Executive 
Order 12866,
    (2) Is not a ``significant rule'' under 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.

Adoption of the Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA amends part 39 of the Federal Aviation 
Regulations (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:

2014-07-02 Rolls-Royce Deutschland Ltd & Co KG (Type Certificate 
previously held by Rolls-Royce Deutschland GmbH and BMW Rolls-Royce 
Aero Engines): Amendment 39-17816; Docket No. FAA-2012-1202; 
Directorate Identifier 2012-NE-38-AD.

(a) Effective Date

    This AD is effective May 8, 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 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 are 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, 
Initial Issue, dated October 30, 2012, for more information. You may 
examine the MCAI in the AD docket on the Internet at http://www.regulations.gov/#!documentDetail;D=FAA-2012-1202-0005.

(j) Material Incorporated by Reference

    None.

    Issued in Burlington, Massachusetts, on March 27, 2014.
Robert J. Ganley,
Acting Assistant Directorate Manager, Engine & Propeller Directorate, 
Aircraft Certification Service.
[FR Doc. 2014-07444 Filed 4-2-14; 8:45 am]
BILLING CODE 4910-13-P