DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-2021; Project Identifier AD-2023-01077-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 adopt a new airworthiness directive (AD)
for certain Gulfstream Aerospace Corporation Model GVII-G500 and GVII-
G600 airplanes. This proposed AD was prompted by a report of cracking
in the electrical grounding receptacles located on the left and right
wings. This proposed AD would require inspecting the electrical
grounding receptacles for cracks and corrosion, performing applicable
on-condition actions, and sealing over the grounding receptacles on the
top of the wings to permanently disable the receptacle. 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 October 7,
2024.

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 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.
AD Docket: You may examine the AD docket at regulations.gov under
Docket No. FAA-2024-2021; 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.
Material Incorporated by Reference: For Gulfstream
material identified in this AD, contact Gulfstream Aerospace
Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, GA
31402-2206; telephone 800-810-4853; email pubs@gulfstream.com; website
gulfstream.com/en/customer-support.
You may view this material 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 at regulations.gov under
Docket No. FAA-2024-2021.

FOR FURTHER INFORMATION CONTACT: Harun Kalin, Aviation Safety Engineer,
FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: 404-474-5576;
email: 9-ASO-ATLACO-ADs@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-2024-2021; Project Identifier
AD-2023-01077-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
this 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
regulations.gov, including any personal information you provide. The
agency will also post a report summarizing each substantive verbal
contact received about this NPRM.

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 Harun Kalin, Aviation Safety Engineer,
FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: 404-474-5576;
email: 9-ASO-ATLACO-ADs@faa.gov. Any commentary that the FAA receives
that is not specifically designated as CBI will be placed in the public
docket for this rulemaking.

Background

The FAA has received a report of cracks found in the electrical
grounding receptacles located on the left and right wings of certain
Gulfstream Aerospace Corporation Model GVII airplanes. Further
investigation revealed that the cracks were initiated by the collection
of water in the electrical grounding receptacle leading to corrosion
and mechanical stresses from water freeze and thaw cycles. Water can
leak through the o-ring/pin interface of the grounding receptacle and
fill the housing over time. The subsequent freeze and thaw cycles of
the entrapped water over multiple flights resulted in cracking and
failures within the receptacle, which can be exacerbated by corrosion.
Fuel vapors can escape through a cracked receptacle during over-wing
fueling operations. When the ground crew attempts to connect equipment
to grounding receptacle a spark from refueling equipment could ignite
flammable fuel mixture in the fuel tank. Fuel leaking from the
electrical grounding receptacles could result in a potential source of
ignition in a fuel tank and consequent fire or explosion.

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.

Material Incorporated by Reference Under 1 CFR Part 51

The FAA reviewed Gulfstream GVII-G500 Customer Bulletin No. 089,
dated November 28, 2023; and Gulfstream GVII-G600 Customer Bulletin No.
058, dated November 28, 2023. This material specifies procedures for
the following actions:
Borescope inspections for cracking and corrosion of the
interior walls of the grounding receptacle casing.
Measurement of the inner diameter of the grounding
receptacle if any Level 1 corrosion is found.
Repair including cleaning and application of chemical
conversion coating if any Level 1 corrosion within the specified
tolerance (inner diameter) is found.
Replacement of the grounding receptacle assembly if any
crack, any Level 2 or Level 3 corrosion, or any level 1 corrosion
outside of the specified tolerance is found.
Removal of the ``GROUND HERE'' decal/stencil from the
grounding receptacles, and application of epoxy over the ground
receptacle area to permanently disable the receptacles.
These documents are distinct since they apply to different airplane
models.
This material 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 require accomplishing the actions specified
in the material already described, except for any differences
identified as exceptions in the regulatory text of this proposed AD.
For information on the procedures and compliance times, see this
material at regulations.gov by searching for and locating Docket No.
FAA-2024-2021.

Costs of Compliance

The FAA estimates that this AD, if adopted as proposed, would
affect 236 airplanes of U.S. registry. The FAA estimates the following
costs to comply with this proposed AD:

Estimated Costs

The FAA estimates the following costs to do any necessary
corrective actions that would be required based on the results of the
proposed inspections. The agency has no way of determining the number
of aircraft that might need these actions:

On-Condition Costs

The FAA has included all known costs in its cost estimate.
According to the manufacturer, however, some or all the costs of this
proposed 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.

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 this 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 adding the following new airworthiness
directive: