[Federal Register Volume 89, Number 182 (Thursday, September 19, 2024)]
[Proposed Rules]
[Pages 76752-76759]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-21209]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2024-2143; Project Identifier AD-2024-00008-A]
RIN 2120-AA64


Airworthiness Directives; Piper Aircraft, Inc. 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 Piper Aircraft, Inc. (Piper) Model PA-28-140, PA-28-150, 
PA-28-160, PA-28-180, PA-28S-160, PA-28S-180, PA-28-236, PA-28-201T, 
PA-32-300, PA-32R-300, PA-32RT-300, PA-32RT-300T, PA-32-301FT, PA-32-
301XTC, PA-32R-301 (HP), PA-32R-301 (SP), PA-32R-301T, PA-32-301, and 
PA-32-301T airplanes. This proposed AD was prompted by a report of a 
wing separation caused by fatigue cracking in a visually inaccessible 
area of the lower main wing spar cap and additional reports of fatigue 
cracking in the wing spars of airplanes that share common type design 
features. This proposed AD would require reviewing airplane maintenance 
records to determine if an eddy current inspection of the lower main 
wing spar bolt holes was done and, depending on the result, doing a 
one-time eddy current inspection of the lower wing spar bolt holes for 
crack(s), and replacing any cracked main wing spar. 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 November 4, 
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

[[Page 76753]]

No. FAA-2024-2143; 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 Piper material identified in this proposed AD, contact 
Piper Aircraft, Inc., 2926 Piper Drive, Vero Beach, Florida 32960; 
phone: (772) 567-4361; email: piper.com">customerservice@piper.com; website: 
piper.com.
     You may view this material 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: Fred Caplan, Aviation Safety Engineer, 
FAA, 1701 Columbia Avenue, College Park, GA 30337; phone: (404) 474-
5507; 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 the ADDRESSES section. Include ``Docket No. FAA-2024-2143; 
Project Identifier AD-2024-00008-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 revise 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 Fred 
Caplan, Aviation Safety Engineer, FAA, 1701 Columbia Avenue, College 
Park, GA 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 issued AD 2020-26-16, Amendment 39-21371 (86 FR 3769, 
January 15, 2021) (AD 2020-26-16), for certain Piper Model PA-28-151, 
PA-28-161, PA-28-181, PA-28-235, PA-28R-180, PA-28R-200, PA-28R-201, 
PA-28R-201T, PA-28RT-201, PA-28RT-201T, PA-32-260, PA-32-300, PA-32R-
300, PA-32RT-300, and PA-32RT-300T airplanes. AD 2020-26-16 was 
prompted by an accident involving wing separation on a Piper Model PA-
28R-201 airplane. An investigation by the National Transportation 
Safety Board (NTSB) revealed a fatigue crack in a visually inaccessible 
area of the lower main wing spar cap. The applicability of the NPRM for 
AD 2020-26-16 included additional Piper model airplanes with similar 
main wing spar structures as the Model PA-28R-201. Based on airplane 
usage history, the FAA determined that only those airplanes with a 
higher risk for fatigue cracks (airplanes with a significant history of 
operation in flight training or other high-load environments) should be 
subject to the inspection requirements proposed in that NPRM.
    AD 2020-26-16 requires calculating the factored service hours for 
each main wing spar to determine when an inspection is required, 
inspecting the lower main wing spar bolt holes for cracks, and 
replacing any cracked main wing spar. The agency issued AD 2020-26-16 
to detect and correct fatigue cracks in the lower main wing spar cap 
bolt holes.

Actions Since AD 2020-26-16 Was Issued

    The preamble to AD 2020-26-16 explains that the FAA considers the 
requirements ``interim action'' and was considering further rulemaking. 
The FAA has now determined that further rulemaking is necessary, and 
this proposed AD and a separate proposed rulemaking action (Docket No. 
FAA-2024-2142) that would supersede AD 2020-26-16 follows from that 
determination. Similar to AD 2020-26-16, this proposed AD is also 
considered to be an interim action that would determine the need for 
additional actions in the fleet addressed currently. The FAA evaluated 
the inspection reports submitted by operators as required by AD 2020-
26-16 and determined that wing spars from additional Piper airplane 
models should be inspected.
    Since the FAA issued AD 2020-26-16, the FAA has analyzed the 
accident history of the airplanes affected by AD 2020-26-16 and other 
Piper airplanes operated in a similar fashion. The following paragraphs 
communicate the FAA's findings on this subject.

Accident History

    Fatigue cracking was present in the main wing spars of Piper Model 
PA-28-181, Model PA-28R-201, and Model PA-28-161 airplanes involved in 
the following accidents. The following NTSB reports are related to this 
issue and can be found on ntsb.gov.
     NTSB Accident Number FTW87FA088: March 30, 1987--Marlin, 
TX--Piper Model PA-28-181--7,490 hours time-in-service (TIS). This 
accident was determined to have been caused by fatigue cracking in the 
outboard bolt holes of the main wing spar. This airplane's primary 
usage was a ``Pipeline Patrol'' mission.
     NTSB Accident Number NYC93FA140: August 2, 1993--
Provincetown, MA--Piper Model PA-28-181--11,683 hours TIS. This 
accident was determined to have been caused by structural overloading 
related to weather, but fatigue cracks were present near the outboard 
bolt holes. This airplane's usage history included personal use, flight 
instruction, and charter flights.
     NTSB Accident Number ERA18FA120: April 4, 2018--Daytona 
Beach, FL--Piper Model PA-28R-201--7,691 hours TIS. This accident was 
determined to have been caused by fatigue cracking in the outboard bolt 
holes of the main wing spar. This airplane's primary usage was flight 
instruction.

Bolt Hole Cracks and Other Findings

    Following the release of AD 2020-26-16, the FAA and Piper received 
over 2,800 bolt-hole eddy current inspection reports. The inspections 
performed in the field revealed a mix of observations that warrant 
further discussion. Of the total inspections, over 100 reported a 
positive eddy current indication, with several including pictures of 
the bolt

[[Page 76754]]

hole showing the source of the indication.
    Piper later conducted more detailed inspections in a study of 24 
main wing spars with 20 having positive eddy current indications. Out 
of the 20 positive indications, 3 were identified as fatigue cracks, 
where 1 was confirmed by Piper, and 2 were confirmed by the NTSB. The 
remaining were determined to be features not consistent with a crack, 
and 1 overstress crack as confirmed by the NTSB.
    Though not all are confirmed, many of the indications are likely 
not fatigue cracks but are a variety of anomalies in the hole. These 
can include corrosion pitting, scratches, gouges, and threading marks 
possibly caused by forceful insertion and removal of the close-fit 
bolts without proper unloading of the wing or other reasons. While 
these may not present as fatigue cracks at the time of inspection, 
anomalies in the hole create a stress concentration where cracks can 
begin to grow. Therefore, it is still crucial to inspect the critical 
bolt holes for these issues and take corrective action to prevent the 
formation of fatigue cracks. Piper Service Bulletin No. 1345, Revision 
A, dated September 17, 2021 (Piper SB No. 1345, Revision A); and Piper 
Service Bulletin No. 1412, dated May 7, 2024 (Piper SB No. 1412), 
include procedures for distinguishing between indications caused by 
hole damage or other anomalies from those caused by cracks.
    In addition to the various forms of non-crack hole damage, the 
inspections revealed several cracks in and around the bolt holes. As 
part of the AD 2020-26-16 inspection reports, 6 cracks were found, 
including 2 later verified by NTSB lab examination and 1 verified by 
Piper (from the Piper study referenced above), and 3 visible cracks in 
photos. Other known cracks include those found in an airplane in the 
same fleet as the 2018 accident airplane, a separately submitted crack 
finding confirmed with dye penetrant, and a crack located on the lower 
spar cap surface running alongside the inspection bolt holes. Given 
these findings, additional cracks may be present among the other 
unconfirmed reported indications.
    Other cracks have been discovered that may be caused by overload 
rather than by fatigue. While use of the airplane within its limits 
should not cause an overload crack, some crack findings have revealed 
that airplanes have been operated outside their limits. Though cracks 
due to overload are not the primary source of this corrective action, 
this emphasizes the need for and importance of inspecting the spar bolt 
holes for evidence of any cracking.

Long-Term Continued Operational Safety

    The AD 2020-26-16 inspection report results indicated that 
additional inspections are needed to manage the safety of the fleet. 
Data indicates that more airplanes will need to be inspected, including 
the need to expand inspections to Piper airplane models that share a 
similar structural design of the main wing spar beyond the models 
addressed in AD 2020-26-16.
    Crack development is a function of many factors, including the 
design of the structure, how severely the aircraft is flown, and 
manufacturing processes. Small imperfections may exist in any aircraft 
structure from an early age; however, through operation, these 
imperfections may slowly grow into fatigue cracks. Fatigue cracks have 
the effect of weakening the structure and its ability to support the 
stresses the airplane was originally designed to handle.
    The 2018 accident, along with other accidents in this fleet 
attributed to fatigue cracking, and the AD 2020-26-16 inspection 
reports, indicate an aging fleet that requires intervention to ensure 
any fatigue cracking does not reach a critical state prior to being 
detected.
    Ensuring further damage is not caused by an inspection itself is 
important; however, inspecting for fatigue cracks as well as other hole 
anomalies is critical and outweighs the risk associated with doing the 
inspections. Piper has developed service actions, most recently in 
Piper SB No. 1345, Revision A; and Piper SB No. 1412, that mitigate 
inspection-induced damage by emphasizing proper unloading of the wing 
for both bolt and wing removal and replacement, if necessary, along 
with other instructions for ensuring care of the bolt holes.

Corrective Action Development

    Each requirement outlined in this proposed AD has been developed to 
both address the unsafe condition and limit the number of required 
inspections, reducing the burden on operators where possible. A brief 
discussion of each aspect of the requirements continues below.

Airplane Model Grouping

    The inspection data received via the reporting requirement in AD 
2020-26-16, along with testing of the baseline spar common to all Piper 
Model PA-28 and PA-32 airplanes, has shown that inspections should be 
extended to include Piper airplane models that share similar structural 
design but were not included in the applicability of AD 2020-26-16. It 
is likely that a significant contributing factor in the formation of 
cracks found in the main wing spar bolt attachment area is the cold 
bending of the spar to achieve the wing's dihedral. This method of 
forming the spar dihedral combined with the proximity to the wing 
attachment bolt holes leads to high residual stress in that area. The 
potential for fatigue cracking in and around the bolt holes, as well as 
higher variability in crack location and severity, is higher under this 
constant additional stress.
    In an attempt to support less onerous inspections and to understand 
the causal factors, Piper investigated the residual stresses in the 
critical bolt-hole area. That investigation showed that the residual 
stress due to the spar cold bending process is a significant 
contributing factor in reducing the fatigue life of the spar bolt 
holes. An additional outcome of this investigation is a change to all 
new manufactured spars having machined dihedral bends to eliminate the 
residual stresses in the critical area.
    Though there are differences between all Model PA-28 and PA-32 
airplanes, such as additional reinforcing structure and lower 
operational loads, all airplane models share this same baseline spar 
with the cold bent dihedral. Differing characteristics allow for a 
grouping and tailoring of the requirements for each airplane model, but 
all airplane models need to be inspected. The airplane models in the 
applicability of this proposed AD are not the same airplane models that 
are included in the applicability of the proposed rulemaking action 
(Docket No. FAA-2024-2142) that would supersede AD 2020-26-16, and the 
proposed required actions are different between these two proposed 
rulemaking actions.
    The remaining Piper Model PA-28 and PA-32 airplanes that would not 
be included in the applicability of this proposed AD either experience 
higher operational loads or have less structure. Both of these 
conditions increase the stress experienced in the subject bolt holes of 
the baseline spar and thus are subject to the proposed rulemaking 
action (Docket No. FAA-2024-2142) to supersede AD 2020-26-16.

Determination of Inspection Compliance Time

    The proposed compliance time for the eddy-current inspection 
specified in this proposed AD was based on an inspection report 
received in response to AD 2020-26-16 that showed a crack indication in 
a Model PA-32-300 wing

[[Page 76755]]

spar, later verified by Piper as a crack. Some airplanes in the 
proposed applicability of this AD may have been inspected as part of 
the requirements of AD 2020-26-16; however, if cracks in the wing spar 
are not expected as early due to the structural differences discussed 
above, these inspections may not yield the intended insight into the 
state of the wing spars. Therefore, the current proposed compliance 
time was set near and prior to the time-in-service of this confirmed 
crack finding in a wing spar of the same population as those in the 
airplanes in the applicability of this proposed AD.
    Wing spars on the affected Piper airplanes could develop cracks 
that, if not addressed, would result in a wing separating from the 
fuselage in flight.

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 Piper Service Bulletin 1412, dated May 7, 2024. 
This material specifies procedures for doing a one-time eddy current 
inspection of the lower wing spar bolt holes for crack(s) and replacing 
any cracked main wing spar. This material also includes instructions to 
report the results of the inspection to Piper. 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.

Proposed AD Requirements in This NPRM

    This proposed AD would require reviewing airplane maintenance 
records to determine if an eddy current inspection of the lower main 
wing spar bolt holes was done and depending on the result, doing an 
eddy current inspection of the lower wing spar for crack(s) if not 
previously done or if done prior to 12,000 hours TIS, and replacing any 
cracked main wing spar. This proposed AD would also require sending all 
inspection results to Piper and the FAA.

Differences Between This Proposed AD and the Referenced Material

    Piper SB 1412 specifies to contact Piper for disposition if any 
non-crack damage is found in the main wing spar bolt holes or any 
crack(s) or non-crack damage is found in the spar box bolt holes but 
this proposed AD would require contacting either the Manager, East 
Certification Branch, FAA, or the Piper Organization Designation 
Authorization (ODA) for instructions and doing those actions. To be 
approved, the repair method, modification deviation, or alteration 
deviation must meet the certification basis of the airplane, and the 
approval must specifically refer to the proposed AD.
    Piper SB 1412 specifies using its feedback form to report the 
inspection results but this proposed AD would require using the form 
included as Appendix 1 to this proposed AD.

Interim Action

    The FAA considers that this proposed AD would be an interim action. 
The proposed inspection reports would provide the FAA with additional 
data for determining the number of cracks present in the fleet. After 
analyzing the data, the FAA may take further rulemaking action.

Costs of Compliance

    The FAA estimates that this AD, if adopted as proposed, would 
affect 10,927 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
----------------------------------------------------------------------------------------------------------------
Review airplane maintenance records...  1 work-hour x $85 per                 $0             $85        $928,795
                                         hour = $85.
----------------------------------------------------------------------------------------------------------------

    The FAA estimates the following costs to do any necessary actions 
that would be required based on the results of the proposed airplane 
maintenance records review. The agency has no way of determining the 
number of airplanes that might need these actions:

                                               On-Condition Costs
----------------------------------------------------------------------------------------------------------------
                  Action                            Labor cost           Parts cost        Cost per product
----------------------------------------------------------------------------------------------------------------
Eddy current inspection of the left and    1 work-hour contracted               $20  $960.
 right lower main wing spar (including      service x $600 per hour =
 access and restoring the airplane).        $600 for the eddy current
                                            inspection.
                                           4 work hours x $85 per       ...........  ...........................
                                            hours = $340 for access
                                            and restoration.
Report inspection results................  1 work-hours x $85 per hour            0  $85.
                                            = $85.
Replace main wing spar...................  40 work-hours x $85 per           10,983  $14,383 per main wing spar.
                                            hour = $3,400 per main
                                            wing spar.
----------------------------------------------------------------------------------------------------------------

Paperwork Reduction Act

    A federal agency may not conduct or sponsor, and a person is not 
required to respond to, nor shall a person be subject to a penalty for 
failure to comply with a collection of information subject to the 
requirements of the Paperwork Reduction Act unless that collection of 
information displays a currently valid OMB Control Number. The OMB 
Control Number for this information collection is 2120-0056. Public 
reporting for this collection of information is estimated to be 
approximately 1 hour per response, including the time for reviewing 
instructions, searching existing data sources, gathering and 
maintaining the data needed, and completing and reviewing the 
collection of information. All responses to this collection of 
information are mandatory. Send comments regarding this burden estimate 
or any other aspect of this

[[Page 76756]]

collection of information, including suggestions for reducing this 
burden, to: Information Collection Clearance Officer, Federal Aviation 
Administration, 10101 Hillwood Parkway, Fort Worth, TX 76177-1524.

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:

Piper Aircraft, Inc.: Docket No. FAA-2024-2143; Project Identifier 
AD-2024-00008-A.

(a) Comments Due Date

    The FAA must receive comments on this airworthiness directive 
(AD) by November 4, 2024.

(b) Affected ADs

    None.

(c) Applicability

    This AD applies to Piper Aircraft, Inc. (Piper) airplanes, 
certificated in any category, with a model and serial number shown 
in Table 1 to the introductory text of paragraph (c) of this AD and 
that meet at least one of the criteria in paragraphs (c)(1) or (2) 
of this AD.

    Table 1 to the Introductory Text of Paragraph (c)--Applicability
------------------------------------------------------------------------
               Model                             Serial Nos.
------------------------------------------------------------------------
PA-28-140.........................  All serial numbers.
PA-28-150.........................  All serial numbers.
PA-28-160.........................  All serial numbers.
PA-28-180.........................  All serial numbers.
PA-28S-160........................  All serial numbers.
PA-28S-180........................  All serial numbers.
PA-28-236.........................  All serial numbers.
PA-28-201T........................  All serial numbers.
PA-32-300.........................  All serial numbers greater than and
                                     including 32-7940001.
PA-32R-300........................  All serial numbers.
PA-32RT-300.......................  All serial numbers.
PA-32RT-300T......................  All serial numbers.
PA-32-301FT.......................  All serial numbers.
PA-32-301XTC......................  All serial numbers.
PA-32R-301 (HP)...................  All serial numbers.
PA-32R-301 (SP)...................  All serial numbers.
PA-32R-301T.......................  All serial numbers.
PA-32-301.........................  All serial numbers.
PA-32-301T........................  All serial numbers.
------------------------------------------------------------------------

    (1) Has accumulated 12,000 or more total hours time-in-service 
(TIS) on a wing spar; or
    (2) Has missing or incomplete maintenance records.

(d) Subject

    Joint Aircraft System Component (JASC) Code/Air Transport 
Association (ATA) of America Code 5711, WING SPAR.

(e) Unsafe Condition

    This AD was prompted by a report of a wing separation caused by 
fatigue cracking in a visually inaccessible area of the main wing 
lower spar cap and additional reports of fatigue cracking in the 
wing spars of airplanes that share common type design features. The 
FAA is issuing this AD to address fatigue crack(s) in the lower main 
wing spar cap bolt holes. The unsafe condition, if not addressed, 
could result in the wing separating from the fuselage in flight.

(f) Compliance

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

(g) Review Airplane Maintenance Records To Determine When Previous Main 
Wing Spar Inspections Completed

    Within 30 days or 100 hours TIS after the effective date of this 
AD, whichever occurs later, review the airplane maintenance records 
to determine when the previous inspection of each main wing spar was 
completed. The owner/operator (pilot) holding at least a private 
pilot certificate may accomplish this and must enter compliance with 
this paragraph of the AD into the airplane maintenance records in 
accordance with 14 CFR 43.9(a) and 91.417(a)(2)(v). The record must 
be maintained as required by 14 CFR 91.417, 121.380, or 135.439. If 
it can be determined from the airplane maintenance records review 
that an eddy current inspection of the main wing spar was done prior 
to the effective date of this AD at 12,000 hours TIS or greater and 
in accordance with Piper Service Bulletin No. 1345, dated March 27, 
2020; or Piper Service Bulletin 1345A, dated September 17, 2021, 
then you may take credit for the inspection required by paragraph 
(h) of this AD.

(h) Bolt Hole Inspections and Corrective Actions

    (1) Within the compliance time specified in either paragraph 
(h)(1)(i) or (ii) of this AD, as applicable, on both the left and 
right main wing spars, do an eddy current inspection of the inner 
surface of each bolt hole in the lower wing spar cap for crack(s) 
and for non-crack damage (including deep scratches, gouges, and 
thread marks), in accordance with paragraph 5. of the Instructions 
in Piper Service Bulletin No. 1412, dated May 7, 2024 (Piper SB No. 
1412). Although Piper SB No. 1412 specifies NAS 410 Level II or 
Level III certification to perform eddy current and fluorescent 
penetrant inspections, this AD allows Level II or Level III 
qualification standards for inspection personnel using any inspector 
criteria approved by the FAA.
    Note 1 to the introductory text of paragraph (h)(1): FAA 
Advisory Circular 65-31B, ``Training, Qualification, and 
Certification of Nondestructive Inspection Personnel,'' dated 
February 24, 2014, contains FAA-approved Level II and Level III 
qualification standards criteria for personnel doing nondestructive 
test inspections.
    (i) Within 100 hours TIS after complying with paragraph (g) of 
this AD or within 100 hours TIS after a main wing spar accumulates 
12,000 hours TIS, whichever occurs later; or
    (ii) For airplanes with an unknown number of hours TIS on a main 
wing spar, within 100 hours TIS or 60 days after the effective date 
of this AD, whichever occurs later.
    (2) If the eddy current inspection does not identify any 
indications, before further flight,

[[Page 76757]]

install new wing spar bolts and nuts as required by paragraph (j) of 
this AD and report the inspection results as required by paragraph 
(k) of this AD.
    (3) If the eddy current inspection identifies any crack(s), 
indications, or noisy signal, before further flight, do the 
applicable actions specified in paragraph 5.b. through k. of the 
Instructions in Piper SB No. 1412.
    (i) If any non-crack damage is found in the main wing spar bolt 
holes or any crack(s) or non-crack damage is found in the spar box 
bolt holes contact either the Manager, East Certification Branch, 
FAA, or the Piper Organization Designation Authorization (ODA) for 
instructions and do those actions. To be approved, the repair 
method, modification deviation, or alteration deviation must meet 
the certification basis of the airplane, and the approval must 
specifically refer to this AD.
    (ii) If any crack(s) is found in the main wing spar bolt hole, 
replace the main wing spar as required by paragraph (i) of this AD.
    (iii) If no crack(s) or non-crack damage is found in the main 
wing spar bolt holes install new main wing spar bolts and nuts as 
required by paragraph (j) of this AD.

(i) Replace Main Wing Spar

    If any crack is found during the inspection required by 
paragraph (h) of this AD, before further flight, replace the 
affected main wing spar with a new (zero hours TIS) main wing spar 
or with a serviceable (more than zero hours TIS) main wing spar that 
has passed the eddy current inspection required by paragraph (h) of 
this AD.

(j) Install New Main Wing Spar Bolts and Nuts

    Before further flight, after completing the actions required by 
paragraph (h) or (i) of this AD, install new main wing spar bolts 
and nuts in accordance with paragraph (step) 9 of the Instructions 
in Piper SB No. 1412.

(k) Report Inspection Results

    At the applicable time specified in paragraph (k)(1) or (2) of 
this AD, report the inspection results to the FAA, East 
Certification Branch, and to Piper Aircraft, Inc., using Appendix 1, 
``Inspection Results Form,'' of this AD,
    (1) If the action was done on or after the effective date of 
this AD, submit the report within 30 days after the action was done.
    (2) If the action was done before the effective date of this AD, 
submit the report within 30 days after the effective date of this 
AD.

(l) Credit for Previous Actions

    If the inspections of the main wing spars required by paragraph 
(h) of this AD were done before the effective date of this AD at 
12,000 hours TIS or greater in accordance with Piper Service 
Bulletin No. 1345, dated March 27, 2020; or Piper Service Bulletin 
1345A, dated September 17, 2021, then you may take credit for these 
inspections.

(m) Special Flight Permit

    A special flight permit may be issued in accordance with 14 CFR 
21.197 and 21.199 to permit a one-time, non-revenue ferry flight to 
a location where the airplane can be inspected. This ferry flight 
must be performed with only essential flight crew. This AD prohibits 
a special flight permit if any inspection reveals a crack in the 
main wing spar.

(n) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, East 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 East Certification Branch, send it to 
the attention of the person identified in paragraph (o)(1) of this 
AD and email to: [email protected].
    (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.

(o) Additional Information

    (1) For more information about this AD, contact Fred Caplan, 
Aviation Safety Engineer, FAA, East Certification Branch, FAA, 1701 
Columbia Avenue, College Park, GA 30337; phone: (404) 474-5507; 
email: [email protected].
    (2) Piper material identified in this AD that is not 
incorporated by reference is available at the address specified in 
paragraph (p)(3) of this AD.
    (3) FAA Advisory Circular 65-31B, ``Training, Qualification, and 
Certification of Nondestructive Inspection Personnel,'' dated 
February 24, 2014, may be found at drs.faa.gov.

(p) Material Incorporated by Reference

    (1) The Director of the Federal Register approved the 
incorporation by reference (IBR) of the material listed in this 
paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
    (2) You must use this material as applicable to do the actions 
required by this AD, unless the AD specifies otherwise.
    (i) Piper Service Bulletin No. 1412, dated May 7, 2024.
    (ii) [Reserved].
    (3) For Piper material identified in this AD, contact Piper 
Aircraft, Inc., 2926 Piper Drive, Vero Beach, FL 32960; phone: (772) 
567-4361; email: piper.com">customerservice@piper.com; website: piper.com.
    (4) You may view this material 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].

[[Page 76758]]

Appendix 1 to Docket No. FAA-2024-2143
[GRAPHIC] [TIFF OMITTED] TP19SE24.053



[[Page 76759]]


    Issued on September 10, 2024.
Victor Wicklund,
Deputy Director, Compliance & Airworthiness Division, Aircraft 
Certification Service.
[FR Doc. 2024-21209 Filed 9-18-24; 8:45 am]
BILLING CODE 4910-13-P