DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0751; Directorate Identifier 2012-SW-051-AD]
RIN 2120-AA64

Airworthiness Directives; AgustaWestland S.p.A. (Type Certificate
Formerly Held by Agusta S.p.A) (Agusta) Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Proposed rule; withdrawal.

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SUMMARY: The FAA is withdrawing a notice of proposed rulemaking (NPRM)
that proposed to supersede Airworthiness Directive (AD) 2011-18-52,
which applies to certain Agusta Model AB139 and AW139 helicopters. AD
2011-18-52 requires establishing a revised life limit for each tail
rotor blade (blade), updating the existing historical records for your
helicopter, repetitively inspecting each blade for a crack, and
replacing certain blades. The NPRM was prompted by the manufacturer
developing an improved blade using different materials and establishing
life limits for those newly-designed blades. The NPRM proposed to
require expanding the applicability to include the newly-designed
blades and establish their life limits, and proposed to retain the
requirement to inspect each blade for a crack and, if there is a crack,
replace each blade with an airworthy blade. Since issuance of the NPRM,
the FAA has determined that the NPRM does not adequately address the
identified unsafe condition. Accordingly, the NPRM is withdrawn.

DATES: The FAA is withdrawing the proposed rule published September 5,
2013 (78 FR 54596), as of February 25, 2021.

ADDRESSES:

Examining the AD Docket

You may examine the AD docket on the internet at https://www.regulations.
gov by searching for and locating Docket No. FAA-2013-0751;
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 action, the European Aviation Safety Agency (now European Union
Aviation Safety Agency (EASA) AD, any comments received, and other
information. The street 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.

FOR FURTHER INFORMATION CONTACT: Matt Fuller, AD Program Manager,
Operational Safety Branch, Airworthiness Products Section, General
Aviation & Rotorcraft Unit, FAA, 10101 Hillwood Pkwy., Fort Worth, TX
76177; telephone 817-222-5110; email matthew.fuller@faa.gov.

SUPPLEMENTARY INFORMATION:

Discussion

The FAA issued an NPRM to amend 14 CFR part 39 to supersede AD
2011-18-52, Amendment 39-17020 (77 FR 23109, April 18, 2012) (AD 2011-
18-52). AD 2011-18-52 applies to Agusta Model AB139 and AW139
helicopters with a blade part number (P/N) 3G6410A00131 or P/N
4G6410A00131 installed. AD 2011-18-52 requires establishing a revised
life limit for each blade, updating the existing historical records for
your helicopter, repetitively inspecting each blade for a crack, and
replacing certain blades. The NPRM published in the Federal Register on
September 5, 2013 (78 FR 54596). The NPRM was prompted by the
manufacturer first developing two new blades with an improved design
and specified life limits and repetitive inspections for the blades.
Also, EASA issued AD No. 2012-0030, dated February 17, 2012, which
superseded EASA EAD No. 2011-0156-E, dated August 25, 2011, to add the
new blades to the required actions. The manufacturer then developed two
new blades with improved materials and specified new life limits and
inspections for the blades. EASA then issued EASA AD No. 2012-0076,
dated May 2, 2012, revised by EASA AD No. 2012-0076R1, dated July 13,
2012 (EASA AD No. 2012-0076R1), to require the repetitive inspections
and reduced life limits on the additional new blades.

Actions Since the NPRM Was Issued

After issuance of the NPRM, EASA issued EASA AD No. 2012-0076R2,
dated February 20, 2014, which revises EASA AD No. 2012-0076R1, to
remove the repetitive 25 flight-hour inspections for blades P/N
3G6410A00132, P/N 4G6410A00132, P/N 3G6410A00133, and P/N 4G6410A00133
and extend the life limits for T/R blades P/N 3G6410A00133 and P/N
4G6410A00133. Additionally, EASA advised that the life limits for T/R
blades P/N 3G6410A00132 and P/N 4G6410A00132 have been incorporated in
the Chapter 4 airworthiness limitations section of the maintenance
manual. Further, since the FAA issued the NPRM, a significant amount of
time has elapsed, which would require the FAA to reopen the comment
period to allow the public an opportunity to comment on the proposed
actions. Accordingly, the FAA has determined the NPRM does not
adequately address the identified unsafe condition and has determined
to withdraw the published NPRM and proceed with a separate rulemaking
to address this unsafe condition.

Withdrawal of the NPRM constitutes only such action and does not
preclude the FAA from further rulemaking on this issue, nor does it
commit the FAA to any course of action in the future.

Comments

The FAA gave the public the opportunity to comment on the NPRM. The
FAA received comments from one commenter.

One commenter requested the FAA adjust the life limit for certain
part-numbered blades to be more consistent with aviation standard
practices and gave the examples of "3 years since initial
installation" and "5 years since manufacture." Since the FAA is
withdrawing the NPRM, the commenter's request to adjust the compliance
time is no longer necessary.

FAA's Conclusions

Upon further consideration, the FAA has determined that the NPRM
does not adequately address the identified unsafe condition and the
unsafe condition will be addressed in a separate AD. Accordingly, the
NPRM is withdrawn.

Regulatory Findings

Since this action only withdraws an NPRM, it is neither a proposed
nor a final rule. This action therefore is not covered under Executive
Order 12866, the Regulatory Flexibility Act, or DOT Regulatory Policies
and Procedures (44 FR 11034, February 26, 1979).

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.