DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2021-0560; Project Identifier MCAI-2021-00192-T;
Amendment 39-21764; AD 2021-21-04]
Airworthiness Directives; Bombardier, Inc., Airplanes
AGENCY: Federal Aviation Administration (FAA), Department of
ACTION: Final rule.
SUMMARY: The FAA is adopting a new airworthiness directive (AD)
certain Bombardier, Inc., Model BD-700-1A10 and BD-700-1A11 airplanes.
This AD was prompted by reports that the sliding bushings in the
forward engine mount system were missing. This AD requires an
inspection (gap check) of the front and aft engine mounts to verify the
proper installation of the sliding bushings, and repair if necessary.
The FAA is issuing this AD to address the unsafe condition on these
DATES: This AD is effective December 8, 2021.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of December 8,
ADDRESSES: For service information identified in this final rule,
contact Bombardier, Inc., 200 Cote-Vertu Road West, Dorval,
Quebec H4S 2A3, Canada; telephone 514-855-2999; email
firstname.lastname@example.org; internet https://www.bombardier.com. You
may view this service information at the FAA, Airworthiness Products
Section, Operational Safety Branch, 2200 South 216th St., Des Moines,
WA. For information on the availability of this material at the FAA,
call 206-231-3195. It is also available on the internet at https://www.
regulations.gov by searching for and locating Docket No. FAA-2021-0560.
Examining the AD Docket
You may examine the AD docket on the internet at https://www.regulations.gov
by searching for and locating Docket No. FAA-2021-
0560; 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, 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: Elizabeth Dowling, Aerospace Engineer,
Mechanical Systems and Administrative Services Section, FAA, New York
ACO Branch, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590;
telephone 516-228-7300; fax 516-794-5531; email email@example.com.
Transport Canada Civil Aviation (TCCA), which is the aviation
authority for Canada, has issued TCCA AD CF-2021-04, dated February 15,
2021 (also referred to as the Mandatory Continuing Airworthiness
Information, or the MCAI), to correct an unsafe condition for certain
Bombardier, Inc., Model BD-700-1A10 and BD-700-1A11 airplanes. You may
examine the MCAI in the AD docket on the internet at https://www.regulations.gov
by searching for and locating Docket No. FAA-2021-0560.
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain Bombardier,
Inc., Model BD-700-1A10 and BD-700-1A11 airplanes. The NPRM published
in the Federal Register on July 9, 2021 (86 FR 36243). The NPRM was
prompted by reports that the sliding bushings in the forward engine
mount system were missing. The NPRM proposed to require an inspection
(gap check) of the front and aft engine mounts to verify the proper
installation of the sliding bushings, and repair if necessary. The FAA
is issuing this AD to address redistribution of load/stress on the
mount components, which may decrease the component fatigue life;
failure of the mount structural components could result in the loss of
the engine attachment to the airframe. See the MCAI for additional
The FAA gave the public the opportunity to participate in
developing this final rule. The following presents the comment received
on the NPRM and the FAA's response to the comment.
Request To Update Certain Service Information and Provide Credit for
Actions Accomplished Using Previous Service Information
Bombardier, Inc., stated that Bombardier Service Bulletin 700-71-
005, dated December 14, 2020, has been updated to Bombardier Service
Bulletin 700-71-005, Revision 01, dated April
16, 2021. Bombardier, Inc., commented that the revised service
information provides a clarification specifically for a German
registered airplane having a serial number with a specific
configuration from a previous repair; no other changes were made
between revision levels. Bombardier, Inc., requested that, if
Bombardier Service Bulletin 700-71-005, Revision 01, dated April 16,
2021, is referenced, credit be provided for operators that have
previously completed the applicable actions using Bombardier Service
Bulletin 700-71-005, dated December 14, 2020.
The FAA agrees to update this final rule to reference Bombardier
Service Bulletin 700-71-005, Revision 01, dated April 16, 2021, for the
reasons provided above; the technical content and the intent of the
service information remains unchanged. The FAA has also added paragraph
(i) of this AD to provide credit for Bombardier Service Bulletin 700-
71-005, dated December 14, 2020, for previous actions that were
performed before the effective date of this AD. In addition, subsequent
paragraphs have been re-identified accordingly.
The FAA reviewed the relevant data, considered the comment
received, and determined that air safety and the public interest
require adopting this final rule with the change described previously
and minor editorial changes. The FAA has determined that these minor
Are consistent with the intent that was proposed in the
NPRM for addressing the unsafe condition; and
Do not add any additional burden upon the public than was
already proposed in the NPRM.
The FAA also determined that these changes will not increase the
economic burden on any operator or increase the scope of this final
Related Service Information Under 1 CFR Part 51
Bombardier, Inc., has issued the following service information.
Bombardier Service Bulletin 700-1A11-71-005, dated
December 14, 2020.
Bombardier Service Bulletin 700-71-005, Revision 01, dated
April 16, 2021.
Bombardier Service Bulletin 700-71-5005, dated December
Bombardier Service Bulletin 700-71-5501, dated December
Bombardier Service Bulletin 700-71-6005, dated December
Bombardier Service Bulletin 700-71-6501, dated December
This service information describes procedures for verifying the
proper installation of the sliding bushings by doing an inspection (gap
check), including a gap outside acceptable limits, a missing or damaged
nut or bolt at the upper side of front mount beam, and a bolt that
turns freely with finger pressure. These documents are distinct since
they apply to different airplane serial numbers. 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.
Costs of Compliance
The FAA estimates that this AD affects 376 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:
Estimated Costs for Required Actions
|11 work-hours x $85 per hour
The FAA has received no definitive
data on which to base the cost
estimates for the repairs specified in this AD.
The FAA has included all known costs in its cost estimate.
According to the manufacturer, however, some or all of the costs of
this AD may be covered under warranty, thereby reducing the cost impact
on affected operators.
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
Adoption of the Amendment
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