[Federal Register Volume 88, Number 66 (Thursday, April 6, 2023)]
[Proposed Rules]
[Pages 20436-20438]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-07010]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-0659; Project Identifier AD-2022-01404-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-G600 airplanes. 
This AD was prompted by a failure that occurred during flight testing 
of a Gulfstream Model GVII-G500 airplane, when the aircraft was 
configuring for a steep approach test point, the crew received a flap 
failure message that was a result of a disconnect of the left hand flap 
due to structural failure. This AD requires revising the airworthiness 
limitations section (ALS) of the instructions for continued 
airworthiness (ICA) or inspection program for the airplane to establish 
a life limit for certain left-hand and right-hand inboard flap yoke 
fittings. 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 May 22, 
2023.

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-2023-0659; 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: Jeffrey Johnson, Aerospace Engineer, 
Airframe Section, FAA, Atlanta ACO Branch, 1701 Columbia Avenue, 
College Park, GA 30337; phone: 404-474-5554; email: [email protected].

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-2023-0659; Project Identifier 
AD-2022-01404-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 20437]]

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 Jeffrey Johnson, Aerospace Engineer, 
Airframe Section, FAA, Atlanta ACO Branch, 1701 Columbia Avenue, 
College Park, GA 30337; phone: 404-474-5554; email: [email protected]. 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 that a failure occurred during flight 
testing of a Gulfstream Model GVII-G500 airplane, which is structurally 
similar to the GVII-G600 airplane, when the aircraft was configuring 
for a steep approach test point, the crew received a flap failure 
message. After an investigation, it was discovered that the left-hand 
flap track ``B'' yoke became disconnected due to structural failure. 
Gulfstream's investigation revealed that certain left-hand and right-
hand inboard flap yoke fittings have fatigue life design flaws, 
including insufficient shaft diameter, a small fillet radius detail on 
the shaft, and rough surface finish. These design flaws attributed to 
higher stress concentrations which could cause fracture of the flap 
actuator yoke at the junction of the fitting shaft and yoke clevis. 
Gulfstream revised the ALS for the applicable airplanes to establish a 
life limit for the affected inboard flap yoke fittings. The design 
flaws, if not addressed, could result in the flaps being jammed in the 
position when the fracture occurred. Additional failures in the flap 
actuator force limiter, or flap yoke actuator disconnect, could result 
in asymmetric flap positions leading to a loss of control of the 
airplane.

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.

Proposed AD Requirements in This NPRM

    This proposed AD would require revising the ALS of the existing ICA 
or inspection program for the airplane to establish a life limit of 
4,000 flight cycles for the left-hand part number (P/N) 73P5755033M005 
and right-hand P/N 73P5755033M006 inboard flap yoke fittings.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 41 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
----------------------------------------------------------------------------------------------------------------
Revise ALS............................  1 work-hour x $85 per             N/A              $85           $3,485
                                         hour = $85.
----------------------------------------------------------------------------------------------------------------

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

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-2023-0659; Project 
Identifier AD-2022-01404-T.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by May 22, 2023.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Gulfstream Aerospace Corporation Model GVII-
G600 airplanes, certificated in any category, serial numbers 73001 
through 73051 inclusive.

(d) Subject

    Air Transport Association (ATA) of America Code 27, Flight 
Controls.

(e) Unsafe Condition

    This AD was prompted by a failure that occurred during flight 
testing of a Gulfstream Model GVII-G500 airplane, when the aircraft 
was configuring for a steep approach test point, the crew received a 
flap failure message that was a result of a disconnect of the left 
hand flap due to structural failure. Gulfstream's investigation 
revealed the need to establish a life limit for the affected inboard 
flap yoke fittings. The FAA is issuing this AD to address design 
flaws that cause decreased fatigue life of the yoke fittings and 
attribute to higher stress concentrations at the junction of the 
fitting shaft and yoke clevis. The unsafe condition, if not 
addressed, could result in flaps being jammed in the position when 
the fracture occurred. Additional

[[Page 20438]]

failures in the flap actuator force limiter, or flap yoke actuator 
disconnect, could result in asymmetric flap positions leading to a 
loss of control of the airplane.

(f) Compliance

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

(g) Incorporation of ALS Revisions

    Within 30 days after the effective date of this AD, revise the 
existing ALS of the ICA or inspection program for your airplane by 
establishing a life limit of 4,000 flight cycles for the left-hand 
part number (P/N) 73P5755033M005 and right-hand P/N 73P5755033M006 
inboard flap yoke fittings.
    Note 1 to paragraph (g): The life limit in paragraph (g) of this 
AD is contained in table 2 in Section 05-10-10 of Gulfstream GVII-
G600 Aircraft Maintenance Manual, Revision 9, dated November 15, 
2022.

(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 responsible Flight Standards 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 responsible Flight Standards Office.

(i) Related Information

    (1) For more information about this AD, contact Jeffrey Johnson, 
Aerospace Engineer, Airframe Section, FAA, Atlanta ACO Branch, 1701 
Columbia Avenue, College Park, GA 30337; phone: 404-474-5554; email: 
[email protected].
    (2) For Gulfstream service information identified in this AD 
that is not incorporated by reference, contact Gulfstream Aerospace 
Corporation, Technical Publications Dept., P.O. Box 2206, Savannah, 
GA 31402-2206; telephone 800-810-4853; email [email protected]; 
website gulfstream.com/en/customer-support/. You may view this 
service information 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.

(j) Material Incorporated by Reference

    None.

    Issued on March 30, 2023.
Christina Underwood,
Acting Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2023-07010 Filed 4-5-23; 8:45 am]
BILLING CODE 4910-13-P


