DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2021-0459; Project Identifier MCAI-2021-00129-T;
Amendment 39-21697; AD 2021-17-14]
RIN 2120-AA64

Airworthiness Directives; Gulfstream Aerospace LP 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 LP Model Gulfstream G280 airplanes. This
AD was prompted by a report that during full-scale fatigue testing, a
crack was found in the area of the attachment of the wing rib 0 to the
front spar. This AD requires non-destructive testing on the forward
(front) spar vertical stiffener and rib 0 for any cracking,
installation of a doubler to the forward (front) spar and rib 0
attachment, and repair if necessary, as specified in a Civil Aviation
Authority of Israel (CAAI) AD, which is incorporated by reference. The
FAA is issuing this AD to address the unsafe condition on these
products.

DATES: This AD is effective October 14, 2021.
The Director of the Federal Register approved the incorporation by
reference of a certain publication listed in this AD as of October 14,
2021.

ADDRESSES: For material incorporated by reference (IBR) in this AD,
contact the CAAI, P.O. Box 1101, Golan Street, Airport City, 70100,
Israel; telephone 972-3-9774665; fax 972-3-9774592; email
aip@mot.gov.il. You may find this IBR material on the CAAI website at
https://www.caa.gov.il. 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 in the AD
docket at https://www.regulations.gov by searching for and locating
Docket No. FAA-2021-0459.

Examining the AD Docket

You may examine the AD docket at https://www.regulations.gov by
searching for and locating Docket No. FAA-2021-0459; 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
mandatory continuing airworthiness information (MCAI), 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: Tom Rodriguez, Aerospace Engineer,
Large Aircraft Section, International Validation Branch, FAA, 2200
South 216th St., Des Moines, WA 98198; telephone and fax 206-231-3226;
email Tom.Rodriguez@faa.gov.

SUPPLEMENTARY INFORMATION:

Background

The CAAI, which is the aviation authority for Israel, has issued
CAAI AD ISR-I-57-2020-06-01, dated January 27, 2021 (CAAI AD ISR-I-57-
2020-06-01) (also referred to as the MCAI), to correct an unsafe condition for
certain Gulfstream Aerospace LP Model Gulfstream G280 airplanes.
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 LP Model Gulfstream G280 airplanes. The NPRM published in the
Federal Register on June 10, 2021 (86 FR 30819). The NPRM was prompted
by a report that during full-scale fatigue testing, a crack was found
in the area of the attachment of the wing rib 0 to the front spar. The
NPRM proposed to require non-destructive testing on the forward (front)
spar vertical stiffener and rib 0 for any cracking, installation of a
doubler to the forward (front) spar and rib 0 attachment, and repair if
necessary, as specified in CAAI AD ISR-I-57-2020-06-01.
The FAA is issuing this AD to address any cracking at the area of
the wing rib 0 to the front spar, which could affect the structural
integrity of the wing. See the MCAI for additional background
information.

Discussion of Final Airworthiness Directive Comments

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
requires adopting this AD as proposed. Except for minor editorial
changes, this AD is adopted as proposed in the NPRM. None of the
changes will increase the economic burden on any operator. Accordingly,
the FAA is issuing this AD to address the unsafe condition on these
products.

Related Service Information Under 1 CFR Part 51

CAAI AD ISR-I-57-2020-06-01 specifies procedures for non-destructive
testing (high frequency, mid frequency, and bolt hole eddy current
inspections; and a liquid (dye) penetrant inspection) for cracking on
the forward (front) spar vertical stiffener and rib 0, installation of
a doubler to the forward (front) spar and rib 0 attachment, and repair
if necessary. 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 the ADDRESSES section.

Costs of Compliance

The FAA estimates that this AD affects 23 airplanes of U.S.
registry. The FAA estimates the following costs to comply with this AD:

Estimated Costs for Required Actions

* If the actions are accomplished during 4C Check.

The FAA has received no definitive data on which to base the cost
estimates for the repair specified in this AD.
According to the manufacturer, some or all of the costs of this AD
may be covered under warranty, thereby reducing the cost impact on
affected operators. The FAA does not control warranty coverage for
affected operators. As a result, the FAA has included all known costs
in the 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.

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: