[Federal Register Volume 78, Number 115 (Friday, June 14, 2013)]
[Proposed Rules]
[Pages 35773-35776]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-14139]


 ========================================================================
 Proposed Rules
                                                 Federal Register
 ________________________________________________________________________
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
 
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 

  Federal Register / Vol. 78, No. 115 / Friday, June 14, 2013 / 
Proposed Rules  

[[Page 35773]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2013-0486; Directorate Identifier 2010-SW-031-AD]
RIN 2120-AA64


Airworthiness Directives; MD Helicopters, Inc. (MDHI), 
Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: We propose to adopt a new airworthiness directive (AD) for the 
MDHI Model MD900 helicopters with certain main rotor blade (MRB) 
retention bolts (bolts) installed. This proposed AD would require a 
daily check of the position of each bolt and would also require a daily 
check and a repetitive inspection for a gap in each bolt. The proposed 
AD would also require, if necessary, removing and inspecting the bolt 
for a crack and replacing any cracked bolt with an airworthy bolt. This 
proposed AD is prompted by multiple reports of in-service bolt 
failures. The proposed actions are intended to prevent failure of a 
bolt, which could lead to loss of MRB structural integrity and 
subsequent loss of control of the helicopter.

DATES: We must receive comments on this proposed AD by August 13, 2013.

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 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 AD, contact 
MDHI, Attn: Customer Support Division, 4555 E. McDowell Rd., Mail Stop 
M615, Mesa, AZ 85215-9734, telephone (800) 388-3378, fax (480) 346-
6813, or at http://www.mdhelicopters.com. You may review copies of the 
referenced service information at the FAA, Office of the Regional 
Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, 
Texas 76137.

FOR FURTHER INFORMATION CONTACT: Roger Durbin, Aerospace Engineer, FAA, 
Los Angeles Aircraft Certification Office, Airframe Branch, ANM-120L, 
3960 Paramount Blvd., Lakewood, CA 90712, telephone (562) 627-5233, fax 
(562) 627-5210, 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

    We propose to adopt a new AD for MDHI Model MD900 helicopters with 
certain bolts installed. This proposed AD is prompted by multiple 
reports of in-service bolt failures, which could lead to loss of the 
MRB structural integrity and subsequent loss of control of the 
helicopter. Although these bolt failures have primarily occurred in the 
United Kingdom, it is possible that the failures affect MDHI Model 900 
helicopters in the United States. This condition, if not detected, 
could lead to loss of MRB structural integrity and subsequent loss of 
control of the helicopter.

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 the same type design.

Related Service Information

    We have reviewed MDHI Alert Service Bulletin SB900-116R1, dated 
April 9, 2010 (ASB SB900-116R1), which supersedes ASB SB900-116, dated 
February 24, 2010 (ASB SB900-116).
    ASB SB900-116 specifies a repetitive check of the blade retention 
bolts, part number (P/N) 900R3100001-103 and 900R3100001-105, for a gap 
and, depending on the outcome of the inspection, removing and 
inspecting the bolt for damage. The ASB also specifies a repetitive 
force check of each bolt, P/N 900R3100001-103, and a torque check of 
each bolt, P/N 900R3100001-105. Lastly, the ASB specifies a daily 
preflight check of each bolt to examine the position of the bolt and 
for a gap, and, if any bolt has moved up or down or if there was no 
gap, removing and inspecting the bolt.
    Superseding ASB SB900-116R1 retains the same specifications as ASB 
SB90016, except that it revises the

[[Page 35774]]

interval for the bolt force and torque checks from 4-6 flight-hours to 
8-10 flight-hours. ASB SB90016R1 also revises the change of force or 
torque from not more than 10 percent to not more than 10 
percent.

Proposed AD Requirements

    The proposed AD would require:
     Before the first flight of each day, visually checking 
each bolt for failure and for a gap between the thrust washer and the 
retainer.
     An owner/operator (pilot) may perform these visual checks 
and must enter compliance into the helicopter maintenance records in 
accordance with 14 CFR 43.9(a)(1)-(4) and 91.417(a)(2)(v). A pilot may 
perform this check because it involves only a visual check for the 
position of the bolt and a check for a gap between the thrust washer 
and retainer and can be performed equally well by a pilot or mechanic. 
This authorization is an exception to our standard maintenance 
regulations.
     If there is any indication of bolt failure or if there is 
no gap between the thrust washer and retainer, before further flight, 
removing and inspecting the bolt for a crack and replacing any cracked 
bolt with an airworthy bolt.
     Within 300 hours time-in-service, and thereafter at 
intervals not to exceed 300 hours TIS, inspecting each bolt for a gap 
between the thrust washer and the retainer.
    [cir] Determining if there is a missing O-ring and installing any 
missing O-ring.
    [cir] If there is no gap between the thrust washer and retainer, 
before further flight, removing and inspecting the bolt for a crack and 
replacing any cracked bolt with an airworthy bolt.
    [cir] If there is a gap between the thrust washer and retainer, 
measuring the gap in two locations with a feeler gage. If the gap is 
too large, removing and inspecting the bolt for a crack, before further 
flight; and then replacing any cracked bolt with an airworthy bolt.

Differences Between This Proposed AD and the Service Information

    This proposed AD uses the term ``inspect'' when describing the 
action of inspecting a bolt for a crack and inspecting for a gap 
between the thrust washer and the retainer. The ASB uses the term 
``check.''

Costs of Compliance

    We estimate that this proposed AD would affect 29 helicopters in 
the U.S. registry. We estimate that operators may incur the following 
costs in order to comply with this AD: The average labor rate is $85 
per work hour. It would take about .5 work hour to do a gap inspection 
of each bolt. It would take about 1 work hour to replace a cracked bolt 
and the required parts would cost $800 at a total cost per helicopter 
of $928.

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):

MD Helicopters, Inc. (MDHI): Docket No. FAA-2013-0486; Directorate 
Identifier 2010-SW-031-AD.

(a) Applicability

    This AD applies to Model MD 900 helicopters with a main rotor 
blade retention bolt (bolt), part number (P/N) 900R3100001-103 or 
900R3100001-105, installed; certificated in any category.

(b) Unsafe Condition

    This AD defines the unsafe condition as bolt failure. This 
condition could result in loss of main rotor blade structural 
integrity and subsequent loss of control of the helicopter.

(c) Comments Due Date

    We must receive comments by August 13, 2013.

(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) Before the first flight of each day:
    (i) Visually check each bolt for failure. Failure of a bolt may 
be indicated by movement of the bolt out of the bolt hole or by 
inconsistent extension of the bolt above or below the other bolts 
being inspected (a failed bolt migrates out of the bolt hole).
    (ii) Visually check for a gap between the thrust washer and the 
retainer, P/N 900R2100009-101 or -103. The thrust washer is depicted 
as item 2 and the retainer is depicted as item 8 in Figure 1 to 
paragraph (e) of this AD.

[[Page 35775]]

[GRAPHIC] [TIFF OMITTED] TP14JN13.002

    (iii) The actions required by paragraphs (e)(1)(i) and 
(e)(1)(ii) may be performed by the owner/operator (pilot) holding at 
least a private pilot certificate and must be entered into the 
aircraft maintenance records showing compliance with this AD in 
accordance with 14 CFR 43.9(a)(1)-(4) and 14 CFR 91.417(a)(2)(v). 
The record must be maintained as required by 14 CFR 91.417, 121.380, 
or 135.439.
    (iv) If there is any indication of bolt failure or if there is 
no gap between the thrust washer and retainer, before further 
flight, remove and inspect the bolt for a crack.

[[Page 35776]]

Replace any cracked bolt with an airworthy bolt.
    (2) Within 300 hours time-in-service (TIS), and thereafter at 
intervals not to exceed 300 hours TIS, inspect each bolt for a gap 
between the thrust washer and the retainer.
    (i) Determine whether an O-ring is installed. Install any 
missing O-ring.
    (ii) If there is no gap between the thrust washer and retainer, 
before further flight, remove and inspect the bolt for a crack. 
Replace any cracked bolt with an airworthy bolt.
    (iii) If there is a gap between the thrust washer and retainer, 
measure the gap in two locations, 180 degrees apart, with a feeler 
gage. If the gap is more than 0.100 inch (2.54 mm) at either 
location, before further flight, remove and inspect the bolt for a 
crack. Replace any cracked bolt with an airworthy bolt.

(f) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles Aircraft Certification Office, 
Airframe Branch (ANM-120L), FAA, may approve AMOCs for this AD. Send 
your request to Roger Durbin, Aerospace Engineer, FAA, Los Angeles 
Aircraft Certification Office, Airframe Branch, ANM-120L, 3960 
Paramount Blvd., Lakewood, CA 90712, telephone (562) 627-5233, fax 
(562) 627-5210, 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 operating any aircraft 
complying with this AD through an AMOC.

(g) Additional Information

    MDHI Alert Service Bulletin SB900-116R1, dated April 9, 2010, 
which supersedes ASB SB900-116, dated February 24, 1010, neither of 
which is incorporated by reference, contains additional information 
about the subject of this AD. For service information identified in 
this AD, contact MDHI, Attn: Customer Support Division, 4555 E. 
McDowell Rd., Mail Stop M615, Mesa, AZ 85215-9734, telephone (800) 
388-3378, fax (480) 346-6813, or at http://www.mdhelicopters.com. 
You may review copies of the service information at the FAA, Office 
of the Regional Counsel, Southwest Region, 2601 Meacham Blvd., Room 
663, Fort Worth, Texas.

 (h) Subject

    Joint Aircraft System Component: 6210: Main rotor blade 
retention bolts.

    Issued in Fort Worth, Texas, on May 29, 2013.
Kim Smith,
Directorate Manager, Rotorcraft Directorate, Aircraft Certification 
Service.
[FR Doc. 2013-14139 Filed 6-13-13; 8:45 am]
BILLING CODE 4910-13-P