DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2018-0866; Product Identifier 2018-SW-083-AD; Amendment
39-21145; AD 2020-12-10]
Airworthiness Directives; Bell Textron Inc. (Type Certificate
Previously Held by Bell Helicopter Textron Inc.) Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule.
SUMMARY: The FAA is superseding Airworthiness Directive (AD) 2011-12-08
for Bell Helicopter Textron Inc. (Bell), Model 205A, 205A-1, 205B, 212,
412, 412CF, and 412EP helicopters. AD 2011-12-08 required a one-time
inspection of the tail rotor (T/R) blade for corrosion and pitting.
This new AD retains the requirements of AD 2011-12-08 while excluding
certain T/R blades from the applicability. This AD was prompted by new
manufacturing and inspection procedures implemented by Bell that
correct the unsafe condition on more recently manufactured T/R blades.
The actions of this AD are intended to address an unsafe condition on
DATES: This AD is effective July 16, 2020.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of July 5, 2011
(76 FR 35334, June 17, 2011).
ADDRESSES: For service information identified in this final rule,
contact Bell Textron Inc., P.O. Box 482, Fort Worth, TX 76101;
telephone 817-280-3391; fax 817-280-6466; or at https://www.bellcustomer.
com. You may view this referenced service information
at the FAA, Office of the Regional Counsel, Southwest Region, 10101
Hillwood Pkwy, Room 6N-321, Fort Worth, TX 76177. It is also available
on the internet at https://www.regulations.gov by searching for and
locating Docket No. FAA-2018-0866.
Examining the AD Docket
You may examine the AD docket on the internet at https://www.regulations.
gov in Docket No. FAA-2018-0866; 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 AD, any service
information that is incorporated by reference, any comments received,
and other information. The street address for Docket Operations is
Docket Operations, U.S. Room W12-140, 1200 New Jersey Avenue SE,
Washington, DC 20590.
FOR FURTHER INFORMATION CONTACT: Kuethe Harmon, Safety Management
Program Manager, DSCO Branch, FAA, 10101 Hillwood Pkwy, Fort Worth, TX
76177; telephone 817-222-5198; email firstname.lastname@example.org.
The FAA issued a notice of proposed rulemaking (NPRM) to amend 14
CFR part 39 to remove AD 2011-12-08, Amendment 39-16715 (76 FR 35334,
June 17, 2011) (``AD 2011-12-08'') and add a new AD. AD 2011-12-08
applied to Bell Model 205A, 205A-1, 205B, 212, 412, 412CF, and 412EP
helicopters with a T/R blade, part number 212-010-750 (all dash
numbers), all serial numbers (S/Ns) except those with a prefix of ``A''
and the number 17061 or larger, and required a one-time inspection of
the T/R blade for corrosion and pitting. The NPRM published in the
Federal Register on April 11, 2019 (84 FR 14626). The NPRM proposed to
retain the requirements of AD 2011-12-08 but remove blades with an S/N
prefix of ``BH'' from the applicability. The proposed actions were
intended to correct the unsafe conditions on these products.
Since the FAA issued the NPRM, Bell Helicopter Textron Inc., has
changed its name to Bell Textron Inc. This final rule reflects that
change and updates the contact information to obtain service
After the NPRM was published, the FAA received comments from five
commenters, four from individuals and one from the European Union
Aviation Safety Agency (EASA). The following presents the comments
received on the NPRM and the FAA's response to each comment.
Support for the NPRM
Two individual commenters supported the NPRM.
Comments Requesting More Information
EASA and an individual commenter requested that the FAA provide
more information about the unsafe condition and the related service
Request: One individual requested details regarding the
manufacturing anomalies due to the chemical milling process, how the
process affected the manufacturing of other parts, and what manufacturing
changes have been made to ensure future problems do not continue.
FAA Response: The FAA agrees to provide additional information. AD
2011-12-08 was issued in 2011 to address manufacturing anomalies in the
chemical milling process. Chem-milled steps are applied to all tail
rotor metal blade spars. Pits in the spars were found along the step of
straight chem-mill cuts. Gas bubbles were trapped on the step of the
cut, and this created pits down the length of the step in the radius.
To address this, Bell advised its supplier to better agitate the tanks,
change the wetting agent, or use vertical racking instead of
horizontal. In addition to corrective actions taken by the chem-mill
supplier, Bell added inspections for chem-mill defects upon receipt of
the spars. No problems have recurred since the AD 2011-12-08 was
issued. This superseding AD does not change any of the corrective
actions from AD 2011-12-08. This superseding AD only excludes a newly
manufactured part that is not subject to the unsafe condition
identified in AD 2011-12-08.
Request: EASA requested the FAA make the Bell service bulletins
referenced in the NPRM available for review in the AD docket. EASA also
asked whether Bell will revise its service bulletins to exclude blades
with the prefix ``BH.''
FAA Response: Because the Bell service bulletins requested by EASA
were incorporated by reference in AD 2011-12-08, they are available on
the internet at https://www.regulations.gov in AD Docket No. FAA-2011-
0561. In addition, they will be available in the AD docket for this new
AD, Docket No. FAA-2018-0866. The FAA is unaware of whether Bell will
revise its service bulletins.
Request for the FAA To Inspect the T/R Blades
One commenter disagreed with the FAA's proposal to supersede the AD
by removing T/R blades with an S/N with a prefix of ``BH'' from the
applicability. The commenter stated that these blades should still be
inspected by the FAA.
FAA Response: The FAA has determined that the unsafe condition
addressed by this AD does not apply to T/R blades with an S/N with a
prefix of ``BH''. Therefore, those blades have been removed from the
applicability. In addition, neither AD 2011-12-08 nor this superseding
AD require operators to have the T/R blades inspected by the FAA.
Instead, the T/R blades must be inspected using standard requirements
under 14 CFR parts 43 and 145.
The FAA has reviewed the relevant information and determined that
an unsafe condition exists and is likely to exist or develop on other
helicopters of these same type designs and that air safety and the
public interest require adopting the AD requirements as proposed.
Related Service Information Under 1 CFR Part 51
The FAA has reviewed the following Bell Alert Service Bulletins,
all Revision A, and all dated December 8, 2009, which specify a one-
time inspection of the T/R blades for corrosion or pitting, and
repairing or replacing the T/R blade if corrosion, pitting, or other
damage is discovered:
Alert Service Bulletin (ASB) No. 205-09-102, for Model
205A and 205A-1 helicopters;
ASB No. 205B-09-54, for Model 205B helicopters;
ASB No. 212-09-134, for Model 212 helicopters;
ASB No. 412-09-136, for Model 412 and 412EP helicopters;
ASB No. 412CF-09-38, for Model 412CF helicopters.
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.
Costs of Compliance
The FAA estimates that this AD affects 384 helicopters of U.S.
Registry. The FAA estimates that operators may incur the following
costs in order to comply with this AD. Labor costs are estimated at $85
Inspecting a T/R blade takes about 10 work-hours and no parts for
an estimated cost of $850 per helicopter and $326,400 for the U.S.
Repairing a T/R blade takes about 10 work-hours and parts cost $750
for an estimated replacement cost of $1,600 per blade.
Replacing a T/R blade takes about 10 work-hours and parts cost
$28,120 for an estimated replacement cost of $28,970 per blade.
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.
The FAA has determined that 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
(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
Adoption of 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.
Sec. 39.13 [Amended]
2. The FAA amends Sec. 39.13 by removing Airworthiness Directive (AD)
2011-12-08, Amendment 39-16715 (76 FR 35334, June 17, 2011), and adding
the following new AD: