DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2021-0257; Project Identifier MCAI-2020-00712-E;
Amendment 39-21772; AD 2021-21-12]
Airworthiness Directives; Rolls-Royce Deutschland Ltd & Co KG
(Type Certificate Previously Held by Rolls-Royce Deutschland GmbH,
Formerly BMW Rolls-Royce GmbH) Turbofan Engines
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
SUMMARY: The FAA is adopting a new airworthiness directive (AD)
certain Rolls-Royce Deutschland Ltd & Co KG (RRD) BR700-710A2-20 model
turbofan engines. This AD was prompted by flight data obtained from
airplanes equipped with certain Rockwell Collins avionics and auto-
throttle systems that demonstrated significant oscillation of the
engine rotor revolution speed during flight. This AD requires initial
and repetitive recalculation of the consumed and remaining service life
of certain life-limited parts (LLPs). This AD also
requires removal of an LLP prior to its approved life limit or within
90 days after the effective date of this AD, whichever occurs later.
The FAA is issuing this AD to address the unsafe condition on these
DATES: This AD is effective December 13, 2021.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of December 13,
ADDRESSES: For service information identified in this final rule,
contact Rolls-Royce Deutschland Ltd & Co KG, Eschenweg 11, Dahlewitz,
15827 Blankenfelde-Mahlow, Germany; phone: +49 (0) 33 7086-4040;
website: https://www.rolls-royce.com/contact-us.aspx. You may view this
service information at the FAA, Airworthiness Products Section,
Operational Safety Branch, 1200 District Avenue, Burlington, MA 01803.
For information on the availability of this material at the FAA, call
(781) 238-7759. It is also available at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0257.
Examining the AD Docket
You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0257; 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 final rule, the
mandatory continuing airworthiness information (MCAI), any comments
received, and other information. The address for Docket Operations is
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: Wego Wang, Aviation Safety Engineer,
ECO Branch, FAA, 1200 District Avenue, Burlington, MA 01803; phone:
(781) 238-7134; fax: (781) 238-7199; email: Wego.Wang@faa.gov.
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain RRD BR700-
710A2-20 model turbofan engines. The NPRM published in the Federal
Register on April 2, 2021 (86 FR 17326). The NPRM was prompted by
flight data obtained from airplanes equipped with certain Rockwell
Collins avionics and auto-throttle systems that demonstrated
significant oscillation of the engine rotor revolution speed during
flight. In the NPRM, the FAA proposed to require initial and repetitive
recalculation of the consumed and remaining service life of certain
LLPs. The NPRM also proposed to require removal of an LLP prior to its
approved life limit or within 90 days after the effective date of this
AD, whichever occurs later. The FAA is issuing this AD to address the
unsafe condition on these products.
The European Union Aviation Safety Agency (EASA), which is the
Technical Agent for the Member States of the European Community, has
issued EASA AD 2018-0268, dated December 11, 2018 and corrected on
February 20, 2019 (referred to after this as ``the MCAI''), to address
the unsafe condition on these products. The MCAI states:
Flight data obtained from aeroplanes equipped with certain
Rockwell Collins avionics and auto-throttle system demonstrated
significant oscillation of the engine rotor revolution speed during
cruise. Analysis indicates that this affects the service life of the
This condition, if not corrected, may lead to failure of an
affected LLP, possibly resulting in release of high-energy debris,
with consequent damage to, and/or reduced control of, the aeroplane.
To address this potentially unsafe condition, RRD issued the NMSB,
providing instructions to recalculate the consumed and remaining
service life of the affected LLP.
For the reasons described above, this [EASA] AD requires
repetitive recalculation of the service life (consumed and
remaining) of each affected LLP and, depending on the results,
replacement of each affected LLP before exceeding the life limit,
taking the re-calculated life consumption into account.
You may obtain further information by examining the MCAI in the AD
docket at https://www.regulations.gov by searching for and locating
Docket No. FAA-2021-0257.
Discussion of Final Airworthiness Directive
The FAA received comments from one commenter, NetJets Aviation
(NJA). The following presents the comments received on the NPRM and the
FAA's response to each comment.
Request To Confirm Compliance With Previous Action
NJA asked if they are in compliance with this AD if they performed
the required actions using Bombardier Service Bulletin (SB) 700-34-5021
or Bombardier SB 700-34-6021, revisions earlier than Revision 3, dated
January 5, 2018, as applicable. NJA reasoned that paragraph (c),
Applicability, of the proposed AD references only Revision 3 of
Bombardier SB 700-34-5021 and Bombardier SB 700-34-6021 (Bombardier
SBs). NJA states that it performed the required actions using Revision
2 of the Bombardier SBs before the effective date of this AD. NJA also
referenced language from Revision 3 of the Bombardier SBs that
indicates no further action is necessary if operators performed the
action using earlier revisions of the Bombardier SBs.
The FAA notes that NJA would be in compliance with the required
actions of this AD if they performed those actions using the earlier
versions of the Bombardier SBs to meet the requirements of this AD. The
FAA updated paragraph (h), Credit for Previous Actions, of this AD to
give credit for using earlier revisions of the Bombardier SBs if the
actions were performed before the effective date of this AD.
Request To Confirm Compliance for Simultaneous Actions
NJA asked if they would be in compliance with the required actions
of this AD, based on paragraph (h), Credit for Previous Actions, if
they complied with the Bombardier SBs and RRD Alert Non-Modification
Service Bulletin SB-BR700-72-A900584, Revision 2, dated November 22,
2017 (the NMSB), at the same time before the fleet accumulated 500
flight cycles. NJA indicated that the Accomplishment Instructions,
paragraphs 3.A.(1) and (2), of the NMSB apply only to the low-pressure
compressor (LPC) disk whereas this AD applies to all LLPs.
The FAA notes that NJA would be in compliance with the replacement
of the LPC disk required by paragraph (g)(3) of this AD if they
performed the action before the effective date of this AD. Paragraph
(f) of this AD mandates compliance with this AD within the compliance
times specified, unless already done.
Update to Service Information
The FAA determined the need to incorporate the latest service
information in this AD. The FAA revised the reference to Bombardier SB
700-34-5021 in paragraph (c) of this AD from Revision 03, dated January
5, 2018, to Revision 04, dated February 11, 2021, or earlier revision,
and Bombardier SB 700-34-6021 in paragraph (c) of this AD from Revision
03, dated January 5, 2018, to Revision 04, dated February 11, 2021, or
earlier revision. This change does not change the number of affected
engines that the FAA estimated in the NPRM and imposes no additional
burden on operators who are required to comply with this AD.
The FAA reviewed the relevant data, considered any comments
received, and determined that air safety requires adopting this AD as
proposed. Accordingly, the FAA is issuing this AD to address the unsafe
condition on these products. Except for minor editorial changes, and
any other changes described previously, this AD is adopted as proposed
in the NPRM. None of the changes will increase the economic burden on
Related Service Information Under 1 CFR Part 51
The FAA reviewed RRD Alert Non-Modification Service Bulletin SB-
BR700-72-A900584, Revision 2, dated November 22, 2017. The NMSB
describes procedures for amending flight cycle counting requirements
for affected LLPs on RRD BR700-710A2-20 model turbofan engines. 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 ADDRESSES.
Other Related Service Information
The FAA reviewed Bombardier SB 700-34-5021, Revision 04, dated
February 11, 2021, and Bombardier SB 700-34-6021, Revision 04, dated
February 11, 2021. These SBs describe procedures for the implementation
of the Global Vision Flight Deck Version 5 (V5) software load on
Bombardier Inc. Model BD-700-1A11 and BD-700-1A10 airplanes,
Costs of Compliance
The FAA estimates that this AD affects 284 engines installed on
airplanes of U.S. registry.
The FAA estimates the following costs to comply with this AD:
|Recalculate service life for
||20 work-hours x $85 per hour
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.
The FAA is 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 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
(2) Will not affect intrastate aviation in Alaska, and
(3) 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
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 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 adding the following new airworthiness