DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2021-0881; Project Identifier AD-2020-01062-T]
Airworthiness Directives; Gulfstream Aerospace Corporation Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
SUMMARY: The FAA proposes to supersede Airworthiness Directive
2020-12-06, which applies to all Gulfstream Aerospace Corporation
(Gulfstream) Model G-IV airplanes. AD 2020-12-06 requires replacing the
nose wheel steering servo valve manifold, incorporating revised
operating procedures into the airplane flight manual (AFM), doing a
records inspection for any incidents of un-commanded nose wheel
steering turns, and reporting the results to the FAA. Since the FAA
issued AD 2020-12-06, the FAA determined that a typographical error was
made in a citing one of the AFM documents. This proposed AD would
retain the actions of AD 2020-12-06 and would correct the citation to
the AFM. The FAA is proposing this AD to address the unsafe condition
on these products.
DATES: The FAA must receive comments on this proposed AD by December
ADDRESSES: You may send comments, using the procedures found in
11.43 and 11.45, by any of the following methods:
Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow
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 NPRM, contact Gulfstream
Aerospace Corporation, P.O. Box 2206, Savannah, GA 31402; phone: (800)
810-4853; email: email@example.com; website: https://www.gulfstream.com/en/customer-support/.
You may view this service
information at the FAA, Airworthiness Products Section,
Operational Safety Branch, FAA, 901 Locust, Kansas City, MO 64106. For
information on the availability of this material at the FAA, call (816)
Examining the AD Docket
You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0881; 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 NPRM, any comments
received, and other information. The street address for Docket
Operations is listed above.
FOR FURTHER INFORMATION CONTACT: Samuel Belete, Aviation Safety
Engineer, Systems and Equipment Section, FAA, Atlanta ACO Branch, 1701
Columbia Avenue, College Park, GA 30337; phone: (404) 474-5580; fax:
(404) 474-5606; email: firstname.lastname@example.org.
The FAA invites you to send any written relevant data, views, or
arguments about this proposal. Send your comments to an address listed
under ADDRESSES. Include ``Docket No. FAA-2021-0881; Project Identifier
AD-2020-01062-T'' at the beginning of your comments. The most helpful
comments reference a specific portion of the proposal, explain the
reason for any recommended change, and include supporting data. The FAA
will consider all comments received by the closing date and may amend
the proposal because of those comments.
Except for Confidential Business Information (CBI) as described in
the following paragraph, and other information as described in 14 CFR
11.35, the FAA will post all comments received, without change, to
https://www.regulations.gov, including any personal information you
provide. The agency will also post a report summarizing each
substantive verbal contact received about this proposed AD.
Confidential Business Information
CBI is commercial or financial information that is both customarily
and actually treated as private by its owner. Under the Freedom of
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public
disclosure. If your comments responsive to this NPRM contain commercial
or financial information that is customarily treated as private, that
you actually treat as private, and that is relevant or responsive to
this NPRM, it is important that you clearly designate the submitted
comments as CBI. Please mark each page of your submission containing
CBI as ``PROPIN.'' The FAA will treat such marked submissions as
confidential under the FOIA, and they will not be placed in the public
docket of this NPRM. Submissions containing CBI should be sent to
Samuel Belete, Aviation Safety Engineer, Systems and Equipment Section,
FAA, Atlanta ACO Branch, 1701 Columbia Avenue, College Park, GA 30337.
Any commentary that the FAA receives which is not specifically
designated as CBI will be placed in the public docket for this
The FAA issued AD 2020-12-06, Amendment 39-21141 (85 FR 36143, June
15, 2020) (AD 2020-12-06), for all Gulfstream Model G-IV airplanes. AD
2020-12-06 was prompted by reports of un-commanded nose wheel steering
turns. AD 2020-12-06 requires replacing the nose wheel steering servo
valve manifold, incorporating revised operating procedures into the
AFM, doing a records inspection for any incidents of un-commanded nose
wheel steering turns, and reporting the results to the FAA. The agency
issued AD 2020-12-06 to prevent moisture from entering the nose
steering wheel servo valve, which could freeze and cause an un-
commanded nose wheel steering position during touchdown.
Actions Since AD 2020-12-06 Was Issued
Since the FAA issued AD 2020-12-06, a typographical error was found
in the title of the AFM required by paragraph (g)(3) of AD 2020-12-06.
The paragraph incorrectly references the document number as ``FAC-AC-
G400-OPS-0001'' instead of ``GAC-AC-G400-OPS-0001.''
The FAA is issuing this NPRM after determining that the unsafe
condition described previously is likely to exist or develop on other
products of the same type design.
Related Service Information Under 1 CFR Part 51
This proposed AD would require Gulfstream IV Customer Bulletin
Number 244, dated March 12, 2018; Gulfstream G300 Customer Bulletin
244, dated March 12, 2018; Gulfstream G400 Customer Bulletin 244, dated
March 12, 2018; Gulfstream IV Airplane Flight Manual, Gulfstream
Aerospace Document Number GAC-AC-GIV-OPS-0001, Revision 52, dated
October 30, 2017; Gulfstream G300 Airplane Flight Manual, Gulfstream
Aerospace Document Number GAC-AC-G300-OPS-0001, Revision 20, dated
October 30, 2017; and Gulfstream G400 Airplane Flight Manual,
Gulfstream Aerospace Document Number GAC-AC-G400-OPS-0001, Revision 20,
dated October 30, 2017; which the Director of the Federal Register
approved for incorporation by reference as of July 20, 2020 (85 FR
36143, June 15, 2020).
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.
Proposed AD Requirements in This NPRM
This proposed AD would retain most of the requirements of AD 2020-
12-06. This proposed AD would require revising the AFM (with the
correct title of the AFM document for G400 airplanes) and replacing the
nose wheel steering servo valve manifold. This proposed AD would also
require doing a records inspection for any incidents of un-commanded
nose wheel steering turns and reporting all recorded occurrences of un-
commanded nose wheel steering turns to the FAA.
Differences Between This Proposed AD and the Service Information
The Gulfstream customer bulletins require reporting compliance with
the bulletins to Gulfstream. This proposed AD does not contain that
requirement; however, this proposed AD would require reporting any
known occurrences of un-commanded nose wheel steering turns to the FAA.
The Gulfstream customer bulletins include a compliance time of 48
months beginning on March 12, 2018. The compliance time for this
proposed AD is 36 months after July 20, 2020 (the effective date of AD
Costs of Compliance
The FAA estimates that this AD, if adopted as proposed, would
affect 425 airplanes of U.S. registry.
The FAA estimates the following costs to comply with this proposed
||Cost on U.S.
|Incorporate AFM revision
||1 work-hour x $85 per hour = $85
|Replace nose wheel steering servo valve
||7 work-hours x $85 per hour = $595
||1 work-hour x $85 per hour = $85
||1 work hour x $85 per hour = $85
The FAA has included all
known costs in its cost estimate.
According to the manufacturer, however, some of the costs of this
proposed AD may be covered under warranty, thereby reducing the cost
impact on affected operators.
Paperwork Reduction Act
A federal agency may not conduct or sponsor, and a person is not
required to respond to, nor shall a person be subject to a penalty for
failure to comply with a collection of information subject to the
requirements of the Paperwork Reduction Act unless that collection of
information displays a currently valid OMB Control Number. The OMB
Control Number for this information collection is 2120-0056. Public
reporting for this collection of information is estimated to be
approximately 1 hour per response, including the time for reviewing
instructions, searching existing data sources, gathering and
maintaining the data needed, and completing and reviewing the
collection of information. All responses to this collection of
information are mandatory. Send comments regarding this burden estimate
or any other aspect of this collection of information, including
suggestions for reducing this burden to: Information Collection
Clearance Officer, Federal Aviation Administration, 10101 Hillwood
Parkway, Fort Worth, TX 76177-1524.
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.
The FAA 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
(1) Is not a ``significant regulatory action'' under Executive
(2) Would not affect intrastate aviation in Alaska, and
(3) Would 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
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
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:
a. Removing Airworthiness Directive 2020-12-06, Amendment 39-21141 (85
FR 36143, June 15, 2020); and
b. Adding the following new airworthiness directive: