[4910-13-P]
DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2024-0232; Project Identifier MCAI-2023-00353-R; Amendment
39-22758; AD 2024-10-12]
RIN 2120-AA64
Airworthiness Directives; Bell Textron Canada Limited Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
SUMMARY: The FAA is adopting a new airworthiness directive (AD) for certain Bell
Textron Canada Limited Model 407 helicopters. This AD was prompted by a report that a
certain part-numbered fuel system standpipe assembly (standpipe) may have sharp edges
at the interval weld joints due to a quality escape during the manufacturing process. This
AD requires inspecting certain fuel system parts and, depending on the inspection results,
taking corrective actions and performing a fuel quantity gauging system calibration.
Depending on the results of the fuel quantity gauging system calibration, this AD requires
performing additional corrective actions and repeating the fuel quantity gauging system
calibration. The FAA is issuing this AD to address the unsafe condition on these
products.
DATES: This AD is effective [INSERT DATE 35 DAYS AFTER DATE OF
PUBLICATION IN THE FEDERAL REGISTER].
The Director of the Federal Register approved the incorporation by reference of
certain publications listed in this AD as of [INSERT DATE 35 DAYS AFTER DATE OF
PUBLICATION IN THE FEDERAL REGISTER].
ADDRESSES:

AD Docket: You may examine the AD docket at regulations.gov under Docket No. FAA2024-0232; 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, 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.
Material Incorporated by Reference:
• For Bell material, contact Bell Textron Canada Limited, 12,800 Rue de
l'Avenir, Mirabel, Quebec J7J 1R4, Canada; phone 1-450-437-2862 or 1-800-363-8023;
fax 1-450-433-0272; email productsupport@bellflight.com; or at
bellflight.com/support/contact-support.
• You may view this material at the FAA, Office of the Regional Counsel,
Southwest Region, 10101 Hillwood Pkwy., Room 6N 321, Fort Worth, TX 76177. For
information on the availability of this material at the FAA, call (817) 222-5110. It is also
available at regulations.gov under Docket No. FAA-2024-0232.
FOR FURTHER INFORMATION CONTACT: Michael Hughlett, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (817)
222-5889; email: michael.Hughlett@faa.gov.
SUPPLEMENTARY INFORMATION:
Background
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part
39 by adding an AD that would apply to Bell Textron Canada Limited Model 407
helicopters, serial numbers 54832 through 54931 inclusive, 54933 through 54939
inclusive, and 54942 through 54954 inclusive, with a certain part-numbered fuel system
standpipe assembly installed. The NPRM published in the Federal Register on February
20, 2024 (89 FR 12792). The NPRM was prompted by Transport Canada AD CF-2023-

11, dated February 23, 2023 (Transport Canada AD CF-2023-11), issued by Transport
Canada, which is the aviation authority for Canada. Transport Canada AD CF-2023-11
states that, due to a quality escape, standpipe part number (P/N) 407-062-032-103 may
have been delivered with sharp edges at the internal weld joints.
In the NPRM, the FAA proposed to require, with the standpipe removed,
inspecting its interior for any sharp edges on each internal weld joint. If there are any
sharp edges on any weld joint, the NPRM proposed to require deburring the edges,
ensuring not to exceed a certain depth into the tube. The NPRM then proposed to require
removing all sanding residue and applying a chemical film to any bare metal surfaces.
The NPRM also proposed to require, with the harness assembly removed, inspecting the
harness assembly connectors for any mechanical damage and corrosion to the electrical
pins, and inspecting the insulation tubing and wires of the harness assembly for any crack
and chafing. Depending on these results, the NPRM proposed to require replacing the
harness assembly.

If the harness assembly was required to be replaced as a result of the proposed
AD requirements, the NPRM proposed to require performing a fuel quantity gauging
system calibration. Depending on the calibration results, the NPRM proposed to require
replacing the harness assembly and repeating the fuel quantity gauging system
calibration. The FAA is issuing this AD to address the unsafe condition on these
products.
You may examine the Transport Canada AD in the AD docket at regulations.gov
under Docket No. FAA-2024-0232.
Discussion of Final Airworthiness Directive

Comments
The FAA received no comments on the NPRM or on the determination of the
costs.
Conclusion
These helicopters have been approved by Transport Canada and are approved for
operation in the United States. Pursuant to the FAA’s bilateral agreement with Canada,
Transport Canada has notified the FAA about the unsafe condition described in its AD.
Except for minor editorial changes, this AD is adopted as proposed in the NPRM.
Accordingly, the FAA is issuing this AD to address the unsafe condition on these
helicopters.
Related Service Information under 1 CFR Part 51
The FAA reviewed Bell Alert Service Bulletin 407-21-124, dated February 1,
2022, which specifies procedures for a one-time visual inspection of the internal weld
joints of standpipe P/N 407-062-032-103. If there are any sharp edges, this service
information specifies rework procedures, which include deburring the sharp edges,
removing all residue, and applying a chemical film. This service information also
specifies procedures to remove and inspect the harness assembly connectors for any
damage to the electrical pins and inspect the insulation tubing and wires for any cracks
and chafing.
Additionally, this service information specifies if any damage is found, contacting
product support engineering and submitting certain information. Finally, this service
information specifies instructions for various fuel procedures and checks.
The FAA also reviewed Fuel Quantity Gauging System, DMC-407-A-95-65-1001A-273A-A, dated June 2, 2022, of Chapter 95 – Instruments, of Bell Model 407
Maintenance Manual, BHT-407-MM, Issue No. 014, dated December 12, 2023, which

specifies procedures for a fuel quantity gauging system calibration procedure and
inspecting the fuel quantity display information.
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 ADDRESSES.
Differences Between this AD and the Transport Canada AD
Transport Canada AD CF-2023-11 requires contacting Bell for disposition
instructions if damage is found on the harness assembly, whereas this AD requires
removing an affected harness assembly from service and replacing it with an airworthy
harness assembly.
Costs of Compliance
The FAA estimates that this AD affects 51 helicopters of U.S. Registry. Labor
rates are estimated at $85 per work-hour. Based on these numbers, the FAA estimates the
following costs to comply with this AD.
Inspecting the interior of the standpipe will take approximately 1 work-hour for
an estimated cost of $85 per helicopter and $4,335 for the U.S. fleet.
Inspecting the harness assembly connectors, insulation tubing, and wiring will
take approximately 1 work-hour for an estimated cost of $85 per helicopter and $4,335
for the U.S. fleet.
If required, deburring, cleaning, and applying a chemical film to each affected
weld joint will take approximately 0.5 work-hour for an estimated cost of $43 per weld
joint.
If required, replacing an affected harness assembly will take approximately 1
work-hour and parts will cost approximately $1,071 for an estimated cost of $1,156 per
harness replacement.
If required, performing a fuel quantity gauging system calibration will take
approximately 10 work-hours for an estimated cost of $850 per procedure.

The FAA has included all known costs in its cost estimate. According to the
manufacturer, however, some of the costs of this AD may be covered under warranty,
thereby reducing the cost impact on affected operators.
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.
§ 39.13 [Amended]
2. The FAA amends § 39.13 by adding the following new airworthiness directive:
2024-10-12 Bell Helicopter Textron Canada Limited: Amendment 39-22758; Docket
No. FAA-2024-0232; Project Identifier MCAI-2023-00353-R.
(a) Effective Date
This airworthiness directive (AD) is effective [INSERT DATE 35 DAYS AFTER
DATE OF PUBLICATION IN THE FEDERAL REGISTER].
(b) Affected ADs
None.
(c) Applicability
This AD applies to Bell Textron Canada Limited Model 407 helicopters, serial
numbers 54832 through 54931 inclusive, 54933 through 54939 inclusive, and 54942
through 54954 inclusive, certificated in any category, with a fuel system standpipe
assembly (standpipe) part number 407-062-032-103 installed.
(d) Subject
Joint Aircraft System Component (JASC) Code: 2897, Fuel system wiring.

(e) Unsafe Condition
This AD was prompted by a report that certain standpipes may have sharp edges
at the interval weld joints due to a quality escape during the manufacturing process. The
FAA is issuing this AD to detect sharp edges in the standpipe. The unsafe condition, if
not addressed, could result in fuel quantity system wiring damage, loss of or erratic fuel
quantity indication.
(f) Compliance
Comply with this AD within the compliance times specified, unless already done.
(g) Requirements
(1) Within 300 hours time-in-service (TIS) or 6 months after the effective date of
this AD, whichever occurs first, accomplish the actions required by paragraphs (g)(1)(i)
and (ii) of this AD.
(i) With the standpipe removed from the aft fuel cell, inspect the interior of the
standpipe for any sharp edges on each internal weld joint, as shown in Figure 1 of Bell
Alert Service Bulletin 407-21-124, dated February 1, 2022. If there is a sharp edge on any
internal weld joint, before further flight, deburr the edges of each affected weld joint
using an aluminum oxide abrasive cloth or paper, or equivalent, ensuring not to exceed
0.015 in (0.38 mm) depth into the tube material at a 45-degree angle to the weld joint.
Then, using a clean cloth dampened with isopropyl alcohol or equivalent, remove all
sanding residue from the weld joint and apply a chemical film material to any bare metal
surfaces.
(ii) With the fuel quantity harness assembly (harness assembly) removed, inspect
the harness assembly connectors for any mechanical damage and corrosion to the
electrical pins and inspect the insulation tubing and wires for any cracks and chafing. For
the purposes of this AD, mechanical damage is indicated by deterioration of the
connections or pins.

(A) If there is any corrosion or mechanical damage, before further flight, remove
the harness assembly from service and replace it with an airworthy harness assembly.
(B) If there is a crack or any chafing, before further flight, remove the harness
assembly from service and replace it with an airworthy harness assembly.
(2) If the harness assembly was required to be replaced as a result of the
inspection required by paragraph (g)(1)(ii) of this AD or by this paragraph, before further
flight, with the standpipe and harness assembly installed, perform a fuel quantity gauging
system calibration in accordance with paragraphs 4 through 18 of Fuel Quantity Gauging
System, DMC-407-A-95-65-10-01A-273A-A, dated June 2, 2022, of Chapter 95 –
Instruments, of Bell Model 407 Maintenance Manual, BHT-407-MM, Issue No. 014,
dated December 12, 2023. As a result of the fuel quantity gauging system calibration, if a
fuel level does not indicate the correct reading or displays no reading, before further
flight, remove the harness assembly from service and replace it with an airworthy harness
assembly; and repeat the actions required by this paragraph for the newly installed
harness assembly.
(h) Alternative Methods of Compliance (AMOCs)
(1) The Manager, International Validation 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 International Validation Branch, send it to the attention of the person
identified in paragraph (i) of this AD. Information may be emailed to: 9-AVS-AIR-730AMOC@faa.gov.
(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. The following provisions also apply to
this AD.
(i) Related Information
For more information about this AD, contact Michael Hughlett, Aviation Safety
Engineer, FAA, 1600 Stewart Avenue, Suite 410, Westbury, NY 11590; phone: (817)
222-5889; email: michael.Hughlett@faa.gov.
(j) Material Incorporated by Reference
(1) The Director of the Federal Register approved the incorporation by reference
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) Bell Alert Service Bulletin 407-21-124, dated February 1, 2022.
(ii) Fuel Quantity Gauging System, DMC-407-A-95-65-10-01A-273A-A, dated
June 2, 2022, of Chapter 95 –Instruments, of Bell Model 407 Maintenance Manual, BHT407-MM, Issue No. 014, dated December 12, 2023.
(3) For Bell Helicopter Textron Canada Limited material, contact Grant Walker,
330 Sparks St, Ottawa, K1A 0N5, Canada; phone: (888) 663-3639; email:
grant.walker@tc.gc.ca.
(4) You may view this material at the FAA, Office of the Regional Counsel,
Southwest Region, 10101 Hillwood Pkwy., Room 6N-321, Fort Worth, TX 76177. 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
fr.inspection@nara.gov.
Issued on July 10, 2024.

James D. Foltz,
Deputy Director, Compliance & Airworthiness Division,
Aircraft Certification Service.
[FR Doc. 2024-15808 Filed: 7/17/2024 8:45 am; Publication Date: 7/18/2024]