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[Federal Register Volume 85, Number 238 (Thursday, December 10, 2020)]
[Proposed Rules]
[Pages 79443-79446]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2020-27059]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2020-0831; Project Identifier 2019-CE-031-AD]
RIN 2120-AA64

Airworthiness Directives; Gulfstream Aerospace Corporation 
Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all Gulfstream Aerospace Corporation (Gulfstream) Model GV 
airplanes. This

[[Page 79444]]

proposed AD was prompted by notification of corrosion present in floor 
beam support links. This proposed AD would require inspecting the right 
butt line 6 floor beam inboard support links and bushings for 
corrosion. 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 January 25, 
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, Technical Publications Dept., P.O Box 2206, 
Savannah, GA 31402-2206; phone: (800) 810-4853; fax: (912) 965-3520; 
email: [email protected]; internet: 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, Missouri 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-2020-0831; 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: Ronald ``Ron'' Wissing, Aviation 
Safety Engineer, Atlanta ACO Branch, FAA, 1701 Columbia Avenue, College 
Park, Georgia 30337; phone: (404) 474-5552; fax: (404) 474-5606; email: 
[email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

    The FAA invites you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2020-0831; 
Project Identifier 2019-CE-031-AD'' 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 
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 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 
Ronald ``Ron'' Wissing, Aviation Safety Engineer, Atlanta ACO Branch, 
FAA, 1701 Columbia Avenue, College Park, Georgia 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 was advised of a failed floor beam support link at right 
butt line (RBL) 6 on a Gulfstream Model GV airplane. The failed support 
link resulted from seizure of the retaining sleeve and bushing at the 
lower attachment point due to undetected corrosion. The floor beam 
support links at RBL 6, fuselage stations (FS) 499, 531, and 569.5 have 
a two-piece installation with straight bushings rather than spherical 
bearings in the inboard link lower end. Design of the support links 
allows floor beam movement when the cabin is pressurized. Seizure of 
the lower bushing will not allow the link assembly to move as designed, 
resulting in bending stress and potential failure of the link, which 
may compromise the integrity of the pressure vessel floor.
    Gulfstream determined that the procedures for the existing Aircraft 
Maintenance Manual (AMM) inspection does not reliably detect corrosion 
in the floor beam support link lower bushings. Accordingly, Gulfstream 
has revised the airworthiness limitation requirements to the AMM by 
adding a detailed inspection with an initial and repetitive inspections 
at intervals of 96 months and including references for removal and 
installation instructions for RBL 6 Floor Beam Support Links.
    This condition, if not addressed, could result in link failure, 
which can compromise the integrity of the pressure vessel floor and 
lead to loss of pressurization to the airplane.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed Gulfstream GV Customer Bulletin Number 231, 
Revision A, dated July 30, 2019 (Gulfstream CB 231A). The service 
information contains procedures for the inspection of the RBL 6, FS 
499, 531, and 569.5, and the bushing in the lower end of the link and 
all attachments for corrosion.
    The FAA reviewed Gulfstream GV AMM, Section 05-10-10, Revision 51, 
dated February 28, 2020. The service information identifies tasks for a 
recurring detailed inspection of the floor beam and wing links FS 465 
through FS 576.
    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.

FAA's Determination

    The FAA is issuing this NPRM after determining that the unsafe 
condition described previously is likely to exist or develop in other 
products of the same type design.

Proposed AD Requirements

    This proposed AD would require a one-time inspection of the RBL 6 
floor beam inboard support links and bushings for corrosion along with 
any repairs necessary. This proposed AD would require a recurring 
inspection of

[[Page 79445]]

the floor beam support links. This proposed AD also recommends sending 
the inspection results to Gulfstream.

Differences Between This Proposed AD and the Service Information

    Gulfstream CB 231A requires reporting the results of the inspection 
to Gulfstream and this proposed AD would not.

Costs of Compliance

    The FAA estimates that this proposed AD would affect 148 airplanes 
of U.S. registry.
    The FAA estimates the following costs to comply with this proposed 
AD:

                                                 Estimated Costs
----------------------------------------------------------------------------------------------------------------
                                                                                     Cost per      Cost on U.S.
              Action                      Labor cost              Parts cost          product        operators
----------------------------------------------------------------------------------------------------------------
Inspection per the Customer        120 work-hours x $85 per  Not applicable.....         $10,200      $1,509,600
 Bulletin, all 3 locations.         hour = $10,200.
Revise the AMM...................  1 work-hour x $85 per     Not applicable.....              85          12,580
                                    hour = $85.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary 
replacements that would be required based on the results of the 
proposed inspection. The FAA has no way of determining the number of 
airplanes that might need these replacements:

                                               On-condition Costs
----------------------------------------------------------------------------------------------------------------
                                                                                                     Cost per
                  Action                                Labor cost                 Parts cost        product
----------------------------------------------------------------------------------------------------------------
Replacement of all 3 links................  40 work-hours x $85 per hour =                $316           $3,716
                                             $3,400.
----------------------------------------------------------------------------------------------------------------

    According to the manufacturer, some of the costs of this proposed 
AD may be covered under warranty, thereby reducing the cost impact on 
affected individuals. The FAA does not control warranty coverage for 
affected operators. 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

    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) 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 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

0
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]

0
2. The FAA amends Sec.  39.13 by adding the following new airworthiness 
directive:

Gulfstream Aerospace Corporation: Docket No. FAA-2020-0831; Project 
Identifier 2019-CE-031-AD.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by January 25, 2021.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Gulfstream Aerospace Corporation Model GV 
airplanes, all serial numbers, certificated in any category.

(d) Subject

    Air Transport Association of America (ATA) Code 53: Fuselage 
Structure.

(e) Reason

    This AD was prompted by a report that current inspection 
procedures of floor beam support links, which can fail due to 
corrosion, are inadequate. The FAA is issuing this AD to detect and 
correct corrosion on a floor beam support link lower bushing. This 
condition, if not addressed, could result in link failure, which can 
compromise the integrity of the pressure vessel floor and lead to 
loss of pressurization of the airplane.

(f) Actions and Compliance

    Comply with this AD within the compliance times specified, 
unless already done.

(g) Action

    (1) Within 24 months after the effective date of this AD, 
inspect the right butt line 6 floor beam inboard support links at 
fuselage stations (FS) 499, 531, and 569.5 for corrosion by 
following the Accomplishment Instructions, steps A through M, of 
Gulfstream GV Customer Bulletin No. 231,

[[Page 79446]]

Revision A, dated July 30, 2019 (Gulfstream CB 231A). Where 
Gulfstream CB 231A specifies contacting Gulfstream for procedures if 
any corrosion is found, you must replace the support link in 
accordance with a method approved by the Manager, Atlanta ACO 
Branch, FAA, before further flight. For a method to be approved by 
the Manager, Atlanta ACO Branch, as required by this paragraph, the 
Manager's approval letter must specifically refer to this AD.
    (2) Within 24 months after the effective date of this AD, revise 
the airworthiness limitations section of your maintenance manual or 
inspection program to incorporate the airworthiness limitations 
specified in Table 13: Fuselage Inspection Table, of Gulfstream GV 
Aircraft Maintenance Manual, Section 05-10-10, Revision 51, dated 
February 28, 2020. Thereafter, except as provided in paragraph (h) 
of this AD, no alternative inspection intervals may be approved for 
the fuselage floor beam and wing link FS 465-FS 576.

(h) 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 (i)(1) of this AD.
    (2) Before using any approved AMOC, notify your appropriate 
principal inspector, or lacking a principal inspector, the manager 
of the local flight standards district office/certificate holding 
district office.
    (3) Except as required by paragraph (g) of this AD: For service 
information that contains steps that are labeled as Required for 
Compliance (RC), the following provisions apply.
    (i) The steps labeled as RC, including substeps under an RC step 
and any figures identified in an RC step, must be done to comply 
with the AD. An AMOC is required for any deviations to RC steps, 
including substeps and identified figures.
    (ii) Steps not labeled as RC may be deviated from using accepted 
methods in accordance with the operator's maintenance or inspection 
program without obtaining approval of an AMOC, provided the RC 
steps, including substeps and identified figures, can still be done 
as specified, and the airplane can be put back in an airworthy 
condition.

(i) Related Information

    (1) For more information about this AD, contact Ronald ``Ron'' 
Wissing, Aviation Safety Engineer, Atlanta ACO Branch, FAA, 1701 
Columbia Avenue, College Park, Georgia 30337; phone: (404) 474-5552; 
fax: (404) 474-5606; email: [email protected].
    (2) For service information identified in this AD, contact 
Gulfstream Aerospace Corporation, Technical Publications Dept., P.O 
Box 2206, Savannah, GA 31402-2206; phone: (800) 810-4853; fax: (912) 
965-3520; email: [email protected]; internet: 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, 
Missouri 64106. For information on the availability of this material 
at the FAA, call (816) 329-4148.

    Issued on December 2, 2020.
Lance T. Gant,
Director, Compliance & Airworthiness Division, Aircraft Certification 
Service.
[FR Doc. 2020-27059 Filed 12-9-20; 8:45 am]
BILLING CODE 4910-13-P
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