
[Federal Register Volume 88, Number 207 (Friday, October 27, 2023)]
[Proposed Rules]
[Pages 73780-73783]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2023-23633]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2023-2005; Project Identifier AD-2022-01523-A]
RIN 2120-AA64


Airworthiness Directives; WACO Classic Aircraft Corporation 
Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain WACO Classic Aircraft Corporation Model 2T-1A-2 airplanes. 
This proposed AD was prompted by reports of multiple types of cracks at 
the leading edge former ribs and trailing edge former ribs in the upper 
wing

[[Page 73781]]

center section. This proposed AD would require installing maneuver 
restriction placards in the front and rear cockpits, inspecting the 
leading and trailing edge former ribs for cracking, replacing any 
cracked ribs, modifying the upper wing center section assembly, and 
removing the maneuver restriction placards after completing the 
modification. 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 
11, 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-2023-2005; 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 service information identified in this NPRM, contact 
WACO Classic Aircraft Corporation, 15955 South Airport Road, Battle 
Creek, MI 49015; phone: (269) 565-1000; email: wacoaircraft.com">hello@wacoaircraft.com.; 
website: wacoaircraft.com.
     You may view this 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 (817) 222-5110.

FOR FURTHER INFORMATION CONTACT: Tim Eichor, Aviation Safety Engineer, 
FAA, 1801 S Airport Road, Wichita, KS 67209; phone: (847) 294-7141; 
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-2023-2005; Project Identifier 
AD-2022-01523-A'' 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 Tim 
Eichor, Aviation Safety Engineer, FAA, 1801 S Airport Road, Wichita, KS 
67209. 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 received reports of multiple types of cracks after low 
flight hours on WACO Classic Aircraft Corporation Model 2T-1A-2 
airplanes. The cracks were approximately 1 to 1.5 inches long and 
located in the leading edge former ribs and trailing edge former ribs 
in the upper wing center section, along the top flange where the ribs 
attach to the spar. Due to the cracking, the fabric support channels 
have come close to separating from the trailing edge former ribs. When 
fabric support channels detach from a rib, they would still be attached 
to the fabric, but the upper center wing airfoil may not maintain its 
shape due to the fabric support channels being pulled up by aerodynamic 
loads, which could lead to unexpected and unknown flight 
characteristics. The type certificate holder determined that this 
unsafe condition affects airplane serial numbers 1200 and subsequent 
with the upper wing center section assembly 30116-100 configuration.
    This condition, if not addressed, could result in reduced 
structural integrity of the airplane and the reduced ability of the 
flightcrew to maintain the safe flight and landing 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.

Related Service Information Under 1 CFR Part 51

    The FAA reviewed WACO Great Lakes 2T-1A-2 Service Bulletin GL-
SB0002, Revision NR, dated July 6, 2023 (WACO SB 2T-1A-2, Revision NR). 
This service information specifies procedures for inspecting the 
leading edge former ribs and trailing edge former ribs in the upper 
wing center section for cracking, replacing any cracked ribs, and 
modifying the upper wing center section assembly by installing new 
fabric support channels, saddles, and brackets. Modifying the upper 
wing center section assembly changes the configuration from the 30116-
100 upper wing center section assembly configuration to the 30116-104 
upper wing center section assembly configuration. 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 require installing maneuver restriction 
placards in the front and rear cockpits, inspecting the leading and 
trailing edge former ribs for cracking, replacing any cracked rib, 
modifying the upper wing center section assembly, and removing the 
maneuver restriction placards after completing the modification.

Difference Between This Proposed AD and the Service Information

    Although section B of the Accomplishment Instructions in WACO SB 
2T-1A-2, Revision NR, specifies to record the locations of all 
identified cracks found on the leading edge former ribs and the 
trailing edge former ribs

[[Page 73782]]

and share this information with WACO Aircraft, this proposed AD would 
not require those actions.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 19 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
----------------------------------------------------------------------------------------------------------------
Maneuver restriction placard            1 work-hour x $85 per                $10             $95          $1,805
 installation/.                          hour = $85.
removal...............................
Rib inspection........................  4 work-hours x $85 per                 0             340           6,460
                                         hour = $340.
Upper wing center assembly              185 work-hours x $85 per           4,063          19,788         375,972
 modification.                           hour = $15,725.
----------------------------------------------------------------------------------------------------------------

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

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
              Action                    Labor cost                Parts cost               Cost per product
----------------------------------------------------------------------------------------------------------------
Rib replacement (8 ribs).........  16 work-hours x $85   $1,032 (8 ribs)............  $2,392 (8 ribs)
                                    per hour = $1,360
                                    (8 ribs).
----------------------------------------------------------------------------------------------------------------

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:

WACO Classic Aircraft Corporation: Docket No. FAA-2023-2005; Project 
Identifier AD-2022-01523-A.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by December 11, 2023.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to WACO Classic Aircraft Corporation Model 2T-
1A-2 airplanes, serial numbers 1200 and subsequent with the 30116-
100 upper wing center section assembly configuration, certificated 
in any category.

(d) Subject

    Joint Aircraft System Component (JASC) Code 5712, Wing, Rib/
Bulkhead.

(e) Unsafe Condition

    This AD was prompted by reports of multiple cracks at the 
leading edge former ribs and trailing edge former ribs in the upper 
wing center section along the top flange where the ribs attach to 
the spar after low flight hours. The FAA is issuing this AD to 
detect and correct cracks in the leading and trailing edge former 
ribs in the upper wing center section. The unsafe condition, if not 
addressed, could result in reduced structural integrity of the 
airplane and the reduced ability of the flightcrew to maintain the 
safe flight and landing of the airplane.

(f) Compliance

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

(g) Required Actions

    (1) Within 30 days after the effective date of this AD, insert 
maneuver restriction placards on the instrument panel of the front 
and rear cockpits, and next to the operating placard in the rear 
cockpit, stating ``NO AEROBATIC MANEUVERS ALLOWED.''
    (2) Within 100 hours time-in-service (TIS) or within 12 months 
after the effective date of this AD, whichever occurs first, 
accomplish the following:
    (i) Inspect the leading edge former ribs and trailing edge 
former ribs in the upper wing center section for cracking in 
accordance with section B and before further flight, replace any 
cracked rib in accordance with section C of the Accomplishment 
Instructions in WACO Great Lakes 2T-1A-2 Service Bulletin GL-SB0002, 
Revision NR,

[[Page 73783]]

dated July 6, 2023 (WACO SB 2T-1A-2, Revision NR). Although section 
B of the Accomplishment Instructions in WACO SB 2T-1A-2, Revision 
NR, specifies to record the locations of all identified cracks found 
on the leading edge former ribs and the trailing edge former ribs 
and share this information with WACO Aircraft, this AD does not 
require those actions.
    (ii) Modify the center section to the 30116-104 upper wing 
center section assembly configuration in accordance with section C 
of the Accomplishment Instructions in WACO SB 2T-1A-2, Revision NR.
    (3) After replacing all cracked ribs and modifying the center 
section to the 30116-104 upper wing center section assembly 
configuration, aerobatic maneuvers can resume and the ``NO AEROBATIC 
MANEUVERS ALLOWED'' maneuver restriction placards can be removed 
from the front and rear cockpits.

(h) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Central Certification 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 Central Certification Branch, send it 
to the attention of the person identified in paragraph (i) 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.

(i) Additional Information

    For more information about this AD, contact Tim Eichor, Aviation 
Safety Engineer, FAA, 1801 S Airport Road, Wichita, KS 67209; phone: 
(847) 294-7141; email: [email protected].

(j) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the service information listed 
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this service information as applicable to do 
the actions required by this AD, unless the AD specifies otherwise.
    (i) WACO Great Lakes 2T-1A-2 Service Bulletin GL-SB0002, 
Revision NR, dated July 6, 2023.
    (ii) [Reserved]
    (3) For service information identified in this AD, contact WACO 
Classic Aircraft Corporation, 15955 South Airport Road, Battle 
Creek, MI 49015; phone: (269) 565-1000; email: 
wacoaircraft.com">hello@wacoaircraft.com; website: wacoaircraft.com.
    (4) You may view this 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 (817) 222-5110.
    (5) You may view this material at the National Archives and 
Records Administration (NARA). For information on the availability 
of this material at NARA, visit www.archives.gov/federal-register/cfr/ibr-locations or email [email protected].

    Issued on October 20, 2023.
Ross Landes,
Deputy Director for Regulatory Operations, Compliance & Airworthiness 
Division, Aircraft Certification Service.
[FR Doc. 2023-23633 Filed 10-26-23; 8:45 am]
BILLING CODE 4910-13-P


