DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2019-1024; Product Identifier 2019-CE-002-AD; Amendment
39-21126; AD 2020-11-01]
RIN 2120-AA64

Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Final rule.

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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for
certain Gulfstream Aerospace Corporation (Gulfstream) Model GVI
airplanes. This AD was prompted by a report that the primary flight
control actuation system (PFCAS) linear variable displacement
transducer (LVDT) mechanical disconnect monitor may not trigger the
disconnect of the affected control surfaces as required in the event of
a control surface failure. This AD requires updating the software of
each PFCAS remote electronics unit (REU), which includes an improvement
to the LVDT. The FAA is issuing this AD to address the unsafe condition
on these products.

DATES: This AD is effective July 27, 2020.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of July 27,
2020.

ADDRESSES: For the Gulfstream and Parker service information identified
in this final rule, contact Gulfstream Aerospace Corporation, Technical
Publications Dept., P.O Box 2206, Savannah, GA 31402-2206; telephone:
(800) 810-4853; fax: (912) 965-3520; email: pubs@gulfstream.com;
internet: https://www.gulfstream.com/customer-support. You may view
this service information at the FAA, Airworthiness Products Section,
Operational Safety Branch, 901 Locust, Kansas City, Missouri 64106. For
information on the availability of this material at the FAA, call (816)
329-4148. It is also available on the internet at https://www.regulations.gov
by searching for and locating Docket No. FAA-2019-1024.

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-2019-
1024; 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 regulatory evaluation, 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: Myles Jalalian, Aerospace Engineer,
Atlanta ACO Branch, FAA, 1701 Columbia Avenue, College Park, Georgia
30337; phone: (404) 474-5572; fax: (404) 474-5606; email:
myles.jalalian@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 by adding an AD that would apply to certain Gulfstream
Aerospace Corporation (Gulfstream) Model GVI airplanes. The NPRM
published in the Federal Register on December 16, 2019 (84 FR 68363).
The NPRM was prompted by a report from Gulfstream that the PFCAS
LVDT mechanical disconnect monitor may not trigger the disconnect of
the affected control surfaces as required in the event of a control
surface failure. The Model GVI flight control computer actuator LVDT
disconnect monitor should disable the control surface for ailerons,
elevators, and rudder in the event that one of those control surfaces
fails. Gulfstream developed an REU software update that provides
improvements to the LVDT of the PFCAS, which addresses the LVDT
disconnect monitor problem.
This condition, if not addressed, could lead to spoiler hard-over
or loss of structural integrity due to excessive surface deflection and
result in loss of control of the airplane.
The NPRM proposed to require updating the software of each PFCAS
REU, which includes an improvement to the LVDT. The FAA is issuing this
AD to address the unsafe condition on these products.

Comments

The FAA gave the public the opportunity to participate in
developing this final rule. The FAA received no comments on the NPRM or
on the determination of the cost to the public.

Conclusion

The FAA reviewed the relevant data and determined that air safety
and the public interest require adopting this final rule as proposed.

Related Service Information Under 1 CFR Part 51

The FAA reviewed Gulfstream G650 Customer Bulletin Number 201,
dated September 28, 2017, and Gulfstream G650ER Customer Bulletin
Number 201, dated September 28, 2017; which specify incorporating
Gulfstream G650 Aircraft Service Change 069, dated September 28, 2017,
or Gulfstream G650ER Aircraft Service Change 069, dated September 28,
2017. This service information differs because each document applies to
a different airplane designation.
The FAA also reviewed Gulfstream G650 Aircraft Service Change 069,
dated September 28, 2017, and Gulfstream G650ER Aircraft Service Change
069, dated September 28, 2017, which provide and reference procedures
for preparing the REU for a software update.
The FAA reviewed Parker Service Bulletin 469000-27-003, Revision 1,
dated October 11, 2017, which contains procedures for updating the
software of the REU from Label 34 to Label 35. This update includes
improved LVDT disconnect and oscillatory monitoring, force fight
mitigation, troubleshooting, and rectification of other reported
problems.
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 161 products installed on
airplanes of U.S. registry.
The FAA estimates the following costs to comply with this AD:

Estimated Costs

According to the manufacturer, some of the costs of this d AD may
be covered under warranty, thereby reducing the cost impact on affected
individuals. The FAA does not control warranty coverage for affected
individuals. As a result, the FAA has included all costs in this cost
estimate.

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.

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) 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
reference, Safety.

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
directive (AD):