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PROPOSED AD GULFSTREAM AEROSPACE CORPORATION: Docket No. FAA-2021-0881; Project Identifier AD-2020-01062-T.
(a) COMMENTS DUE DATE

    The FAA must receive comments on this airworthiness directive (AD)  by
    December 10, 2021.

(b) AFFECTED ADS

    This AD replaces AD 2020-12-06,  Amendment 39-21141 (85 FR 36143, June
    15, 2020) (AD 2020-12-06).

(c) APPLICABILITY

    This AD applies to all Gulfstream Aerospace Corporation Model G-IV air
    -planes, certificated in any category.

(d) SUBJECT

    Joint Aircraft System Component (JASC) Code 3200, Landing Gear System.

(e) UNSAFE CONDITION

    This AD was  prompted by reports  of un-commanded nose  wheel steering
    turns. The FAA  is issuing this  AD 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. The unsafe
    condition,  if  not  addressed,  could  result  in  a  lateral  runway
    departure.

(f) COMPLIANCE

    Comply with this AD within the compliance times specified,  unless al-
    ready done.

(g) RETAINED AIRPLANE FLIGHT MANUAL REVISIONS FOR CERTAIN AIRPLANES

    This paragraph  restates the requirements  of paragraph (g)(1) and (2)
    of AD 2020-12-06.  Within 30 days  after July 20, 2020  (the effective
    date of AD2020-12-06), revise your airplane flight manual (AFM) by in-
    corporating the revision applicable  to your airplane configuration as
    listed in paragraphs (g)(1) and (2) of this AD:

(1) Gulfstream IV  Airplane Flight Manual,  Gulfstream  Aerospace Document
    Number GAC-AC-GIV-OPS-0001, Revision 52, dated October 30, 2017; or

(2) Gulfstream G300 Airplane Flight Manual,  Gulfstream Aerospace Document
    Number GAC-AC-G300-OPS-0001, Revision 20, dated October 30, 2017.

(h) CORRECTION TO AFM REVISION FOR CERTAIN AIRPLANES

    Within 30 days after the effective date of this AD, revise your AFM by
    incorporating Gulfstream G400 Airplane Flight Manual, Gulfstream Aero-
    space Document Number GAC-AC-G400-OPS-0001, Revision 20, dated October
    30, 2017, if applicable to your airplane configuration.

(i) RETAINED REPLACEMENT  OF NOSE WHEEL STEERING SERVO VALVE MANIFOLD WITH
    NO CHANGES

    The paragraph restates the requirements of paragraph (h) of AD 2020-12
    -06  with  no changes.  Within  36 months  after  July 20,  2020  (the
    effective date of AD2020-12-06), replace the nose wheel steering servo
    valve  manifold with  nose wheel  steering servo  valve manifold  part
    number  5100-11  or  5105-5  in  accordance  with  the  Accomplishment
    Instructions of the  customer bulletin that  applies to your  airplane
    configuration as listed in paragraphs  (i)(1) through (3) of this  AD,
    except you are not required to comply with step H:

(1) Gulfstream IV Customer Bulletin Number 244, dated March 12,2018;

(2) Gulfstream G300 Customer Bulletin 244, dated March 12, 2018; or

(3) Gulfstream G400 Customer Bulletin 244, dated March 12, 2018.

(j) RETAINED RECORDS INSPECTION AND REPORT OF RESULTS WITH NO CHANGES

    This paragraph restates the requirements  of paragraph (i) of AD 2020-
    12-06 with no changes.

(1) Between 12 months and 24 months  after  the  replacement  of  the nose
    wheel steering valve manifold assembly  required  in  paragraph (i) of
    this AD,  inspect all aircraft records  for entries of an un-commanded
    nose wheel steering turn.

(2) Within 10 days after the records inspection  required in paragraph (j)
    (1) of this AD,  report the results of the inspection,  regardless  of
    whether the inspection found any entries,  to the FAA by either email:
    9-ASO-ATLCOS-Reporting@faa.gov or by mail: Attn: Continued Operational
    Safety, Atlanta ACO Branch FAA, 1701 Columbia Avenue, College Park, GA
    30337.  The report  must include  as much of the information listed in
    paragraphs (j)(2)(i) through (vii)  of  this  AD as is known about the
    event:

(i) Date of records inspection;

(ii) Date and time of all un-commanded occurrences (if any);

(iii) Airplane serial number;

(iv) Weather and runway conditions at the time of each occurrence;

(v) Copy of the pilot's report of the occurrence (if available);

(vi) Maintenance entry of the root cause  of  the  un-commanded deflection
     (if available); and

(vii) Any other information pertinent to the occurrence.

(k) ALTERNATIVE METHODS OF COMPLIANCE (AMOCS)

(1) The  Manager,  Atlanta ACO Branch,  FAA,  has the authority to approve
    AMOCs for this AD, if requested  using the procedures found in 14  CFR
    39.19. In  accordance with  14 CFR  39.19, send  your request  to your
    principal  inspector  or  local Flight  Standards District  Office, as
    appropriate. If  sending information  directly to  the manager  of the
    certification  office,  send  it  to  the  attention  of  the   person
    identified in paragraph (l)(1) of this AD.

(2) Before using any approved AMOC,  notify your appropriate principal in-
    spector, or lacking  a principal inspector,  the manager of  the local
    flight standards district office/certificate holding district office.

(l) RELATED INFORMATION

(1) For more information about this AD,  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: samuel.belete@faa.gov.

(2) For  service information  identified in this AD,  Gulfstream Aerospace
    Corporation, P.O. Box 2206, Savannah, GA 31402; phone: (800) 810-4853;
    email:  pubs@gulfstream.com;  website:  https://www.gulfstream.com/en/
    customer-support/. You may view this referenced service information at
    the FAA Airworthiness Products Section, Operational Safety Branch, 901
    Locust, Kansas City, MO 64106.  For information on the availability of
    this material at the FAA, call (816) 329-4148.

Issued on October 13, 2021. Lance T Gant, Director, Compliance & Airworth-
iness Division, Aircraft Certification Service.

DATES: The FAA must receive comments  on this proposed AD  by December 10,
2021.
PREAMBLE 

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0881; Project Identifier AD-2020-01062-T]
RIN 2120-AA64

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 (AD)
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
10, 2021.

ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:
Federal eRulemaking Portal: Go to https://www.regulations.gov. Follow the instructions
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: pubs@gulfstream.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)
329-4148.

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: samuel.belete@faa.gov.

SUPPLEMENTARY INFORMATION:

Comments Invited

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
rulemaking.

Background

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.''

FAA's Determination

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
2020-12-06).

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
AD:

Estimated Costs

Action Labor cost Parts cost Cost per product Cost on U.S. operators
Incorporate AFM revision 1 work-hour x $85 per hour = $85 $0 $85 $36,125
Replace nose wheel steering servo valve 7 work-hours x $85 per hour = $595 63,624 64,219 27,293,075
Review records 1 work-hour x $85 per hour = $85 0 85 36,125
Report results 1 work hour x $85 per hour = $85 0 85 36,125

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.

Regulatory Findings

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
regulation:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866,
(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
reference, Safety.

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: