
[Federal Register Volume 77, Number 61 (Thursday, March 29, 2012)]
[Proposed Rules]
[Pages 18963-18965]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2012-7535]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2012-0342; Directorate Identifier 2011-SW-028-AD]
RIN 2120-AA64


Airworthiness Directives; MD Helicopters, Inc.

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to supersede an existing airworthiness directive 
(AD) for MD Helicopters, Inc. (MDHI) Model MD900 helicopters. The 
existing AD requires a visual inspection, and if necessary, an eddy 
current inspection of the main rotor lower hub assembly (lower hub) for 
a crack. If a crack exists, the AD requires replacing the lower hub 
with an airworthy lower hub before further flight. Because that AD was 
immediately effective, we did not include in its requirements certain 
long-term actions that did not necessitate adoption prior to public 
comment. This proposed AD would require those long-term actions. This 
proposed AD would require the same inspections as the existing AD but 
would also require recurring inspections and replacing the lower hub 
with an airworthy lower hub. We are proposing this AD to detect a crack 
in the lower hub and prevent failure of the lower hub and subsequent 
loss of control of the helicopter.

DATES: We must receive comments on this proposed AD by May 29, 2012.

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.

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     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 MD 
Helicopters Inc., Attn: Customer Support Division, 4555 E. McDowell 
Rd., Mail Stop M615, Mesa, AZ 85215-9734, telephone 1-800-388-3378, fax 
480-346-6813, or at http://www.mdhelicopters.com. You may review copies 
of 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: Eric Schrieber, Aviation Safety 
Engineer, Los Angeles Aircraft Certification Office, Transport Airplane 
Directorate, FAA, 3960 Paramount Blvd., Lakewood, CA 90712; telephone 
(562) 627-5348; email eric.schrieber@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

    On June 21, 2011, we issued AD 2011-14-05, amendment 39-16740 (76 
FR 41662, July 15, 2011) for MDHI Model MD900 helicopters with a lower 
hub, part number 900R2101008-107, with serial numbers that begin with 
5009. That AD requires, within 100 hours time-in-service (TIS) or 
during the next annual inspection, whichever occurs first, visually 
inspecting the sides and bottom of the area between the arms for the 
centering bearing and the areas adjacent to the bushings of the lower 
hub assembly for a crack. If a crack exists, before further flight, 
replace the lower hub with an airworthy lower hub. If there is no crack 
as a result of the visual inspection, eddy current inspect the lower 
hub for a crack. If a crack exists, before further flight, replace the 
lower hub with an airworthy hub. The AD requires an inspector qualified 
to ASNT Level II or equivalent to perform the nondestructive eddy 
current inspection of the lower hub. That AD was prompted by cracks 
found on four lower hubs. We issued that AD to detect a crack in the 
lower hub and prevent failure of the lower hub and subsequent loss of 
control of the helicopter.

Actions Since Existing AD Was Issued

    When we issued AD 2011-14-05 (76 FR 41662, July 15, 2011), we 
intentionally did not include certain long-term actions (a 300-hour 
repetitive inspection of the lower hub and a requirement to replace the 
lower hub within three years). We are including these actions in this 
proposed AD to allow public comments before any adoption of the long-
term proposals.

FAA's Determination

    We are proposing this AD because we evaluated all the relevant 
information and determined the unsafe condition described previously is 
likely to exist or develop in other products of the same type design.

Related Service Information

    We reviewed MDHI Service Bulletin SB900-117, dated January 14, 2011 
(SB). The SB specifies an initial 100-hour and recurring 300-hour 
visual and eddy current inspections of the lower hub for a crack and, 
if a crack exists, replacement of the lower hub with an airworthy lower 
hub. The SB requires the inspections at the stated intervals or during 
the next annual inspection, whichever occurs first. The SB also 
specifies replacing the lower hub within three years.

Proposed AD Requirements

    This proposed AD would require the same inspections currently 
required by AD 2011-14-05 (76 FR 41662, July 15, 2011), but would 
require that those inspections also be performed at intervals not to 
exceed 300 hours TIS or during the next annual inspection, whichever 
occurs first. This proposed AD would also require, within three years, 
replacing the lower hub with an airworthy hub not included in the 
Applicability section of this AD. This replacement would provide 
terminating action for this AD's requirements.

Differences Between the Proposed AD and the Service Information

    This proposed AD would not require you to contact the manufacturer 
nor to return the lower hub assembly with a certain report.

Costs of Compliance

    We estimate that this proposed AD would affect 12 helicopters of 
U.S. registry.
    We estimate the following costs to comply with this proposed AD:
     Visually inspecting the hub. We estimate that would take 
one work-hour at $85 an hour, for a total cost per helicopter of $85 
and a total cost of $1,020 for the fleet.
     Eddy current inspecting the lower hub. We estimate that 
would take one work-hour at $85 an hour, for a total cost per 
helicopter of $85 and a total cost of $1,020 for the fleet.
     Replacing the lower hub. We estimate that would take 11 
work-hours at $85 an hour for a total labor cost of $935, and that 
parts would cost $12,480 per hub, for a total cost of $13,415 per 
helicopter and a total cost of $160,980 for the fleet.
     The total of all of the costs listed for U.S. operators 
would be $163,020, assuming that the lower hubs for the entire fleet 
would get replaced.

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:

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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

    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) 2011-14-05, Amendment 39-16740 (76 FR 41662, July 15, 2011), and 
adding the following new AD:

MD Helicopters, Inc. (MDHI): Docket No. FAA-2012-0342; Directorate 
Identifier 2011-SW-028-AD.

(a) Applicability

    This AD applies to MDHI Model MD900 helicopters with main rotor 
lower hub assembly (lower hub) part number 900R2101008-107, with 
serial numbers beginning with 5009, certificated in any category.

(b) Unsafe Condition

    This AD is prompted by the determination that a certain 
manufacturer had incorrectly inserted flanged bushings into the 
lower hub bore. This condition could result in failure of the lower 
hub and subsequent loss of control of the helicopter.

(c) Other Affected ADs.

    This AD supersedes AD 2011-14-05, Amendment 39-16740 (76 FR 
41662, July 15, 2011).

(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) Within 100 hours time-in-service (TIS) or during the next 
annual inspection, whichever occurs first, unless done within the 
last 200 hours TIS, and thereafter at intervals not to exceed 300 
hours TIS or during the next annual inspection, whichever occurs 
first:
    (i) Visually inspect the sides and bottom of the area between 
the arms for the centering bearing and the areas adjacent to the 
bushings of the lower hub assembly for a crack. If there is a crack, 
before further flight, replace the lower hub with an airworthy lower 
hub.
    (ii) If the lower hub is not replaced as a result of the visual 
inspection required by paragraph (e)(1)(i) of this AD, eddy current 
inspect the lower hub for a crack by following the Accomplishment 
Instructions, paragraphs 2.A(2) through 2.A.(10)., of MD Helicopters 
Inc. Service Bulletin SB900-117, dated January 14, 2011 (SB). If 
there is a crack, before further flight, replace the lower hub with 
an airworthy hub.
    (2) The eddy current inspection required by paragraph (e)(1)(ii) 
of this AD must be done by a Level II technician with ASNT-TC-1A, 
CEN EN 4179, MIL-STD-410, NAS410, or equivalent certification in 
eddy current inspections. The technician must have done an eddy 
current inspection in the last 12 months.
    (3) Within 3 years, replace the lower hub with an airworthy 
lower hub not included in the Applicability section of this AD. This 
replacement is terminating action for the requirements of this AD.

(f) Alternative Methods of Compliance (AMOCs)

    (1) The Manager, Los Angeles Aircraft Certification Office 
(LAACO), FAA, may approve AMOCs for this AD. Send your proposal to: 
Eric Schrieber, Aviation Safety Engineer, Los Angeles Aircraft 
Certification Office, Transport Airplane Directorate, FAA, 3960 
Paramount Blvd., Lakewood, CA 90712; telephone (562) 627-5348; email 
eric.schrieber@faa.gov.
    (2) For operations conducted under a Part 119 operating 
certificate or under 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

    For service information identified in this AD, contact MD 
Helicopters Inc., Attn: Customer Support Division, 4555 E. McDowell 
Rd. Mail Stop M615, Mesa, AZ 85215-9734, telephone 1-800-388-3378, 
fax 480-346-6813, or at http://www.mdhelicopters.com. You may 
review copies of this information at the FAA, Office of the Regional 
Counsel, Southwest Region, 2601 Meacham Blvd., Room 663, Fort Worth, 
Texas 76137.

(h) Subject

    Joint Aircraft Service Component (JASC) Code: 6220, Main Rotor 
Head.

    Issued in Fort Worth, Texas, on March 21, 2012.
Kim Smith,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2012-7535 Filed 3-28-12; 8:45 am]
BILLING CODE 4910-13-P


