80 FR 72390 - Airworthiness Directives; Airbus Helicopters (Formerly Eurocopter France) Helicopters

DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration

Federal Register Volume 80, Issue 223 (November 19, 2015)

We propose to adopt a new airworthiness directive (AD) for Airbus Helicopters Model SA341G and SA342J helicopters. This proposed AD would require repetitive inspections of a certain part-numbered main rotor hub torsion bar (torsion bar). This proposed AD is prompted by several cases of corrosion in the metal strands of the torsion bar. The proposed actions are intended to detect corrosion and prevent failure of the torsion bar, loss of a main rotor blade, and subsequent loss of control of the helicopter.

[Federal Register Volume 80, Number 223 (Thursday, November 19, 2015)]
[Proposed Rules]
[Pages 72390-72393]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2015-29402]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2015-5914; Directorate Identifier 2014-SW-056-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Helicopters (Formerly Eurocopter 
France) Helicopters

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for 
Airbus Helicopters Model SA341G and SA342J helicopters. This proposed 
AD would require repetitive inspections of a certain part-numbered main 
rotor hub torsion bar (torsion bar). This proposed AD is prompted by 
several cases of corrosion in the metal strands of the torsion bar. The 
proposed actions are intended to detect corrosion and prevent failure 
of the torsion bar, loss of a main rotor blade, and subsequent loss of 
control of the helicopter.

DATES: We must receive comments on this proposed AD by January 19, 
2016.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Docket: Go to http://www.regulations.gov. Follow the online instructions for sending your 
comments electronically.
     Fax: 202-493-2251.
     Mail: Send comments to the U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue SE., Washington, DC 20590-0001.
     Hand Delivery: Deliver to the ``Mail'' address between 9 
a.m. and 5 p.m., Monday through Friday, except Federal holidays.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov by searching for and locating Docket No. FAA-2015-
5914; or in person at the Docket Operations Office between 9 a.m. and 5 
p.m., Monday through Friday, except Federal holidays. The AD docket 
contains this proposed AD, the European Aviation Safety Agency (EASA) 
AD, the economic evaluation, any comments received, and other 
information. The street address for the Docket Operations Office 
(telephone 800-647-5527) is in the ADDRESSES section. Comments will be 
available in the AD docket shortly after receipt. For service 
information identified in this proposed AD, contact Airbus Helicopters, 
2701 N. Forum Drive, Grand Prairie, TX 75052; telephone (972) 641-0000 
or (800) 232-0323; fax (972) 641-3775; or at http://www.airbushelicopters.com/techpub. You may review the referenced 
service information at the FAA, Office of the Regional Counsel, 
Southwest Region, 10101 Hillwood Pkwy, Room 6N-321, Fort Worth, TX 
76177.

FOR FURTHER INFORMATION CONTACT: Robert Grant, Aviation Safety 
Engineer, Safety Management Group, FAA, 10101 Hillwood Pkwy, Fort 
Worth, Texas 76177; telephone (817) 222-5110; email 
[email protected].

SUPPLEMENTARY INFORMATION: 

Comments Invited

    We invite you to participate in this rulemaking by submitting 
written comments, data, or views. We also invite comments relating to 
the economic, environmental, energy, or federalism impacts that might 
result from adopting the proposals in this document. The most helpful 
comments reference a specific portion of the proposal, explain the 
reason for any recommended change, and include supporting data. To 
ensure the docket does not contain duplicate comments, commenters 
should send only one copy of written comments, or if comments are filed 
electronically, commenters should submit only one time.
    We will file in the docket all comments that we receive, as well as 
a report summarizing each substantive public contact with FAA personnel 
concerning this proposed rulemaking. Before acting on this proposal, we 
will consider all comments we receive on or before the closing date for 
comments. We will consider comments filed after the comment period has 
closed if it is possible to do so without incurring expense or delay. 
We may change this proposal in light of the comments we receive.

Discussion

    EASA, which is the Technical Agent for the Member States of the 
European Union, issued EASA AD No. 2014-0216, dated September 24, 2014, 
to correct an unsafe condition for Airbus Helicopters Model SA341G and 
SA342J helicopters. EASA advises that several cases of cracks were 
found on the polyurethane (PU) coating of part-numbered 704A33633274 
torsion bars installed on military Model SA341 helicopters. EASA states 
that these parts can also be

[[Page 72391]]

installed on civilian Model SA341 and SA342 helicopters. According to 
EASA, analysis of the cracked torsion bars showed small areas of 
superficial corrosion on the strands inside the bars can also develop 
during the manufacturing process. EASA states that cracking of the PU 
coating near these areas and the associated penetration of water can 
lead to further and deeper development of the corrosion. EASA advises 
that this condition, if not detected and corrected, allows water to 
penetrate into the torsion bar causing corrosion and failure of the 
metal strands inside the bar. Failure of the metal strands could lead 
to torsion bar failure, resulting in an in-flight loss of a main rotor 
blade and consequent loss of control of the helicopter.

FAA's Determination

    These helicopters have been approved by the aviation authority of 
France and are approved for operation in the United States. Pursuant to 
our bilateral agreement with France, EASA, its technical 
representative, has notified us of the unsafe condition described in 
its AD. We are proposing this AD because we evaluated all known 
relevant information and determined that an unsafe condition is likely 
to exist or develop on other products of the same type design.

Related Service Information Under 1 CFR Part 51

    We reviewed Airbus Helicopters Gazelle work card 65.12.607, dated 
August 2008. This service information describes inspecting the torsion 
bars for a crack in the PU coating and for corrosion and thickness of 
the bushings.
    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 of this 
NPRM.

Other Related Service Information

    Airbus Helicopters has issued Alert Service Bulletin No. SA341/
SA342-05.40, Revision 0, dated April 28, 2014 (ASB), for Model SA341G 
and SA342J helicopters certificated by the FAA, and military Model 
SA341B, C, D, E, F, and H and SA342K, L, L1, M, M1, and Ma helicopters. 
The ASB specifies repetitively inspecting the torsion bars in 
accordance with certain work cards, including work card 65.12.07. These 
inspections are part of Airbus Helicopters' current maintenance 
program, and the ASB revises the compliance time interval for the 
inspections.

Proposed AD Requirements

    This proposed AD would require removing and performing repetitive 
inspections of each torsion bar for a crack in the PU coating, the 
dimension of the angle between the bushings, corrosion on the inside 
diameter of each bushing, the thickness of each bushing, the size of 
the inside diameter of each bushing, and missing varnish on the two 
faces of each bushing. This proposed AD would require replacing the 
torsion bar before further flight if there is a crack in the PU coating 
of a torsion bar that matches or exceeds the damage criteria, if the 
angle of the torsion bar is 7 degrees or more, if any corrosion on a 
bushing cannot be removed by rubbing it with an abrasive pad, if the 
thickness of a bushing is less than 37.520 mm (1.477 in), or if the 
diameter of a bushing is larger than 21,040 mm (.828 in). If varnish is 
missing from more than 15 percent of the surface area from a face of a 
bushing, this proposed AD would require removing all varnish, finishing 
with an abrasive pad, and applying a coat of paint to the face of the 
bushing.

Differences Between This Proposed AD and the EASA AD

    This proposed AD would require you to replace a torsion bar instead 
of returning it to the manufacturer for examination.

Interim Action

    We consider this proposed AD to be an interim action. If final 
action is later identified, we might consider further rulemaking.

Costs of Compliance

    We estimate that this proposed AD would affect 33 helicopters of 
U.S. Registry.
    We estimate that operators may incur the following costs in order 
to comply with this AD. We estimate $85 per work hour for labor. We 
estimate 8 work hours to inspect each helicopter at an estimated cost 
of $680 per helicopter and $22,440 for the fleet per inspection cycle. 
Replacing a torsion bar would cost $7,020 for required parts; no 
additional labor would be necessary.

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.
    We are 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

    We 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, I certify this proposed regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979);
    3. Will not affect intrastate aviation in Alaska to the extent that 
it justifies making a regulatory distinction; and
    4. 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.
    We prepared an economic evaluation of the estimated costs to comply 
with this proposed AD and placed it in the AD docket.

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 (AD):

Airbus Helicopters (formerly Eurocopter France): Docket No. FAA-
2015-5914; Directorate Identifier 2014-SW-056-AD.

[[Page 72392]]

(a) Applicability

    This AD applies to Model SA341G and SA342J helicopters with a 
main rotor head torsion bar (torsion bar) part number 704A33633274 
installed, certificated in any category.

(b) Unsafe Condition

    This AD defines the unsafe condition as a crack in the coating 
of the torsion bar resulting in corrosion. This condition could 
result in failure of a torsion bar, loss of a main rotor blade, and 
subsequent loss of control of the helicopter.

(c) Comments Due Date

    We must receive comments by January 19, 2016.

(d) Compliance

    You are responsible for performing each action required by this 
AD within the specified compliance time unless it has already been 
accomplished prior to that time.

(e) Required Actions

    (1) For each torsion bar with less than 5 years since the first 
date of installation on any helicopter, within the compliance time 
shown in Table 1 to paragraph (e)(1) of this AD:
    (i) Remove the torsion bar and, using a magnifying glass with a 
maximum magnification level of 10X, visually inspect for a crack in 
the polyurethane (PU) coating of the torsion bar as depicted in 
Figure 1 of Airbus Helicopters Gazelle work card 65.12.607, dated 
August 2008 (work card). Consider two cracks that are less than 5 mm 
(.196 in) apart as a single crack. If there is a crack in the PU 
coating that is more than 5 mm (.196 in), replace the torsion bar 
before further flight. Do not rework the PU coating of the torsion 
bar in any way.
    (ii) Inspect the angle, dimension alpha, as depicted in View on 
Arrow F of Figure 1 of the work card. If the angle is 7 or more 
degrees, replace the torsion bar before further flight.
    (iii) Inspect each bushing for corrosion on the inside diameter. 
If any corrosion cannot be removed by rubbing it with an abrasive 
pad, replace the torsion bar before further flight.
    (iv) Using an outside micrometer, measure the thickness, 
dimension a, of each bushing as depicted in Detail AA of Figure 1 of 
the work card. If the thickness is less than 37.520 mm (1.477 in), 
replace the torsion bar before further flight.
    (v) Using an inside micrometer, measure the inside diameter, 
dimension b, of each bushing as depicted in Detail AA of Figure 1 of 
the work card. If the diameter is larger than 21.040 mm (.828 in), 
replace the torsion bar before further flight.
    (vi) Inspect the two faces of each bushing for missing varnish. 
If varnish is missing from more than 15% of the surface area on a 
face of a bushing, before further flight, remove all varnish using 
400-grit abrasive paper. Finish with an abrasive pad and apply a 
coat of P05 paint to the face of the bushing.

                       Table 1 to Paragraph (e)(1)
------------------------------------------------------------------------
    Time accumulated on torsion bar              Compliance time
------------------------------------------------------------------------
(i) Less than 320 hours time-in-service  Before accumulating 420 hours
 (TIS) since new and has never been       TIS since new or within 24
 inspected in accordance with Airbus      months since the date of first
 Helicopters 341G-342J Airworthiness      installation on any
 Limitations, Revision 18, dated June     helicopter, whichever occurs
 2014 (limitations inspection).           first.
(ii) 320 or more hours TIS since new     Within 100 hours TIS, or before
 and has never had a limitations          accumulating 600 hours TIS
 inspection.                              since new, or within 24 months
                                          since the date of first
                                          installation on any
                                          helicopter, whichever occurs
                                          first.
(iii) Less than 320 hours TIS since the  Before accumulating 420 hours
 last limitations inspection.             TIS since the last limitations
                                          inspection or within 24 months
                                          since the last limitations
                                          inspection, whichever occurs
                                          first.
(iv) 320 or more hours TIS since the     Within 100 hours TIS, or before
 last limitations inspection.             accumulating 600 hours TIS
                                          since the last limitations
                                          inspection, or within 24
                                          months since the last
                                          limitations inspection,
                                          whichever occurs first.
------------------------------------------------------------------------

    (2) For each torsion bar with 5 or more years since the first 
date of installation on any helicopter, within the compliance time 
shown in Table 2 to paragraph (e)(2) of this AD, do the inspections 
required by paragraphs (e)(1)(i) through (vi) of this AD.

                       Table 2 to Paragraph (e)(2)
------------------------------------------------------------------------
    Time accumulated on torsion bar              Compliance time
------------------------------------------------------------------------
(i) Less than 320 hours TIS since new,   Before accumulating 420 hours
 and less than 6 months since the date    TIS since new or within 12
 of first installation on any             months since the date of first
 helicopter, and has never had a          installation on any
 limitations inspection.                  helicopter, whichever occurs
                                          first.
(ii) 320 or more hours TIS since new or  Within 100 hours TIS, or within
 more than 6 months since the date of     6 months, or before
 first installation on any helicopter,    accumulating 600 hours TIS
 and has never had a limitations          since new, or within 24 months
 inspection.                              since the date of first
                                          installation on any
                                          helicopter, whichever occurs
                                          first.
(iii) Less than 320 hours TIS since      Before accumulating 420 hours
 last limitations inspection and less     TIS since last limitations
 than 6 months since the last             inspection or 12 months since
 limitations inspection.                  last limitations inspection,
                                          whichever occurs first.
(iv) 320 or more hours TIS since last    Within 100 hours TIS, or within
 limitations inspection or 6 or more      6 months, or before
 months since the last limitations        accumulating 600 hours TIS
 inspection.                              since the last limitations
                                          inspection, or within 24
                                          months since the last
                                          limitations inspection,
                                          whichever occurs first.
------------------------------------------------------------------------

    (3) Repeat the inspections required by paragraphs (e)(1)(i) 
through (vi) of this AD as follows:
    (i) For torsion bars with less than 6 years since the date of 
installation on any helicopter, at intervals not to exceed 420 hours 
TIS or 24 months, whichever occurs first.
    (ii) For torsion bars with 6 or more years since the date of 
installation on any helicopter, at intervals not to exceed 420 hours 
TIS or 12 months, whichever comes first.

(f) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Safety Management Group, FAA, may approve AMOCs 
for this AD. Send your proposal to: Robert Grant, Aviation Safety 
Engineer, Safety Management Group, FAA, 10101 Hillwood Pkwy, Fort 
Worth, TX 76177; telephone (817) 222-5110; email [email protected].
    (2) For operations conducted under a 14 CFR part 119 operating 
certificate or under 14 CFR part 91, subpart K, we suggest that you 
notify your principal inspector, or lacking a principal inspector, 
the manager of the local flight standards district office or 
certificate holding district office before

[[Page 72393]]

operating any aircraft complying with this AD through an AMOC.

(g) Additional Information

    (1) Airbus Helicopters Alert Service Bulletin ASB No. SA341/
SA342-05.40, Revision 0, dated April 28, 2014, which is not 
incorporated by reference, contains additional information about the 
subject of this AD. For service information identified in this AD, 
contact Airbus Helicopters, 2701 N. Forum Drive, Grand Prairie, TX 
75052; telephone (972) 641-0000 or (800) 232-0323; fax (972) 641-
3775; or at http://www.airbushelicopters.com/techpub. You may review 
the referenced service information at the FAA, Office of the 
Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-
321, Fort Worth, TX 76177.
    (2) The subject of this AD is addressed in European Aviation 
Safety Agency (EASA) AD No. 2014-0216, dated September 24, 2014. You 
may view the EASA AD on the Internet at http://www.regulations.gov 
in the AD Docket.

(h) Subject

    Joint Aircraft Service Component (JASC) Code: 6700 Main Rotor.

    Issued in Fort Worth, Texas, on November 9, 2015.
Lance T. Gant,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2015-29402 Filed 11-18-15; 8:45 am]
BILLING CODE 4910-13-P