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[Federal Register Volume 81, Number 103 (Friday, May 27, 2016)]
[Proposed Rules]
[Pages 33609-33611]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2016-12442]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2016-0733; Directorate Identifier 2015-SW-040-AD]
RIN 2120-AA64

Airworthiness Directives; Robinson Helicopter Company 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 
Robinson Helicopter Company (Robinson) Model R44, R44 II, and R66 
helicopters. This proposed AD would require a visual inspection of the 
main rotor blade (MRB) and either removing or altering it. This 
proposed AD is prompted by a report that a fatigue crack was found at 
an MRB's trailing edge and a determination that some MRBs may have 
reduced blade thickness due to blending out corrosion. The proposed

[[Page 33610]]

actions are intended to prevent an MRB fatigue crack, which could lead 
to MRB failure and subsequent loss of helicopter control.

DATES: We must receive comments on this proposed AD by July 26, 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-2016-
0733, 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 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 rule, contact 
Robinson Helicopter Company, 2901 Airport Drive, Torrance, CA 90505; 
telephone (310) 539-0508; fax (310) 539-5198; or at http://www.robinsonheli.com. 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: Fred Guerin, Aviation Safety Engineer, 
Los Angeles Aircraft Certification Office, Transport Airplane 
Directorate, FAA, 3960 Paramount Blvd., Lakewood, California 90712; 
telephone (562) 627-5232; email fred.guerin@faa.gov.

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

    We propose to adopt a new AD for Robinson Model R44 and R44 II 
helicopters with an MRB part number (P/N) C016-7, Revisions N/C, A 
through Z, and AA through AE; and Model R66 helicopters with an MRB P/N 
F016-2, Revisions A through E. The proposed AD would require a one-time 
inspection of the MRB for a crack, corrosion, dent, nick, or scratch, 
and either altering the MRB or removing it from service.
    On February 23, 2015, we issued Special Airworthiness Information 
Bulletin (SAIB) SW-15-08 for Robinson Model R44 and R44 II helicopters 
with part numbered C016-7 MRBs. SAIB SW-15-08 was prompted by a report 
of an in-flight failure of a MRB on a Robinson Model R44 II helicopter, 
which resulted in severe MRB vibration that prompted an emergency 
landing. SAIB SW-15-08 recommended daily pre-flight visual checks of 
the MRB trailing edge and having a qualified technician examine any 
damage before further flight. SAIB SW-15-08 also recommended, if 
unusual rotor system vibration was detected in flight, landing 
immediately and having a qualified mechanic examine the MRBs.
    After we issued SAIB SW-15-08, Robinson published R44 Service 
Bulletin SB-89, dated March 30, 2015 (SB-89), and R66 Service Bulletin 
SB-13, dated March 30, 2015 (SB-13), recommending inspecting and 
modifying the MRB trailing edge. Therefore, on March 31, 2015, we 
revised the SAIB and issued SAIB SW-15-08R1 to advise that the MRB 
trailing edge has a corner where the blade chord begins to increase 
that can result in high stresses. SAIB SW-15-08R1 recommends inspecting 
and modifying the MRB by following the actions in the service 
information.
    When the SAIBs were issued, we did not consider the reported 
incident to be an airworthiness concern that would warrant AD action. 
The FAA subsequently determined that some of the affected blades have 
been repaired by blending out corrosion in the area of the crack site 
radius, resulting in a reduced blade thickness. Also, reports to 
Robinson following the SB-89 and SB-13 inspections revealed corrosion 
remaining undetected between scheduled maintenance intervals. The 
presence of corrosion and a reduction in blade thickness could result 
in the development of a fatigue crack on the trailing edge at the 
transition radius before the MRB reaches its retirement life. Altering 
the MRB by smoothing the transition at the chord increase, as specified 
in SB-89 and SB-13, reduces the stress concentration and corrects this 
unsafe condition. The proposed actions are intended to prevent a 
fatigue crack, which could lead to failure of the MRB and subsequent 
loss of helicopter control.

FAA's Determination

    We are proposing this AD because we evaluated all known relevant 
information and determined that an unsafe condition exists and is 
likely to exist or develop on other products of these same type 
designs.

Related Service Information Under 1 CFR Part 51

    We reviewed SB-89 for Model R44 and R44 II helicopters and SB-13 
for Model R66 helicopters. SB-89 and SB-13 provide a one-time procedure 
to inspect each MRB for cracks, corrosion, and damage that may indicate 
a crack. If there is a crack, corrosion, or any damage, SB-89 and SB-13 
specify removing the MRB from service and contacting Robinson. 
Otherwise, SB-89 and SB-13 describe procedures to smooth the transition 
at the chord increase of each MRB to reduce the stress concentration.
    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.

Proposed AD Requirements

    This proposed AD would require within 100 hours time-in-service 
(TIS) or at the next annual inspection, whichever occurs first, 
cleaning the MRB and visually inspecting it for a crack, nick, 
corrosion, scratch, or dent.

[[Page 33611]]

If there is any crack, nick, corrosion, scratch or dent, this proposed 
AD would require repairing it or removing the MRB from service. If the 
MRB is repaired, or if there are no cracks, nicks, corrosion, 
scratches, or dents, this proposed AD would require altering the MRB.

Differences Between This Proposed AD and the Service Information

    This proposed AD would require compliance within the next 100 hours 
TIS or at the next annual inspection, whichever occurs first. The 
service information recommends compliance within 15 hours TIS or by May 
31, 2015, whichever occurs first, for the R44 and R44II helicopters and 
10 hours TIS or by May 31, 2015, whichever occurs first, for the R66 
helicopters.

Costs of Compliance

    We estimate that this proposed AD would affect 2,236 helicopters of 
U.S. Registry and that labor costs average $85 per work hour. Based on 
these estimates, we expect the following costs:
     The visual inspection would require 1 work hour. No parts 
would be needed, so the cost per helicopter would total $85. The cost 
for the U.S. fleet would total $190,060.
     Altering each MRB, if necessary, would require 2 work 
hours and $65 for parts. We estimate a total cost of $235 per 
helicopter and $525,460 for the U.S. fleet.
     Replacing a MRB, if necessary, would require 3 work hours. 
Parts would cost $19,900 for the Model R44 and R44 II and $20,900 for 
the R66 helicopter for a total cost of $20,155 and $21,155, 
respectively, per MRB.

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):

Robinson Helicopter Company: Docket No. FAA-2016-0733; Directorate 
Identifier 2015-SW-040-AD.

(a) Applicability

    This AD applies to Robinson Helicopter Company (Robinson) Model 
R44 and R44 II helicopters with a main rotor blade (MRB) part number 
(P/N) C016-7 Revision N/C, A through Z, and AA through AE installed; 
and Model R66 helicopters with a MRB P/N F016-2 Revision A through E 
installed; certificated in any category.

(b) Unsafe Condition

    This AD defines the unsafe condition as a fatigue crack on an 
MRB. This condition could result in failure of an MRB and loss of 
helicopter control.

(c) Comments Due Date

    We must receive comments by July 26, 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

    Within 100 hours time-in-service or at the next annual 
inspection, whichever occurs first:
    (1) Clean each MRB in the area depicted in Figure 1 of Robinson 
R44 Service Bulletin SB-89, dated March 30, 2015 (SB-89), or 
Robinson R66 Service Bulletin SB-13, dated March 30, 2015 (SB-13), 
as applicable to your model helicopter.
    (2) Using 10X or higher power magnification and a light, 
visually inspect the upper and lower MRB surfaces and trailing edge 
as depicted in Figure 1 of SB-89 or SB-13 for a crack, a nick, a 
scratch, a dent, or corrosion. If there is a crack, a nick, a 
scratch, a dent, or any corrosion, repair the MRB to an airworthy 
configuration if the damage is within the maximum repair damage 
limits or remove the MRB from service.
    (3) Alter the MRB in accordance with Compliance Procedure, 
paragraphs 4 through 19, of SB-89 or SB-13, as applicable to your 
model helicopter. Equivalent tubing may be used for R7769-1 and 
R7769-6 tubes. Power tools may not be used for this procedure.

(f) Alternative Methods of Compliance (AMOC)

    (1) The Manager, Los Angeles Aircraft Certification Office, FAA, 
may approve AMOCs for this AD. Send your proposal to: Fred Guerin, 
Aviation Safety Engineer, Los Angeles Aircraft Certification Office, 
Transport Airplane Directorate, FAA, 3960 Paramount Blvd., Lakewood, 
California 90712; telephone (562) 627-5232; email 9-ANM-LAACO-AMOC-REQUESTS@faa.gov.
    (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 operating any aircraft 
complying with this AD through an AMOC.

 (g) Subject

    Joint Aircraft Service Component (JASC) Code: 6210, Main Rotor 
Blades.

    Issued in Fort Worth, Texas, on May 19, 2016.
Scott A. Horn,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2016-12442 Filed 5-26-16; 8:45 am]
 BILLING CODE 4910-13-P
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