AD 2010-18-52
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | MD | Various | Airworthiness Directives; MD Helicopters, Inc. Model MD900 Helicopters |
Unsafe Condition
Crack in the main rotor hub near the flex beam bolt hole locations, which could lead to hub failure and subsequent loss of control of the helicopter.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
Visually inspect the main rotor hub for a crack, paying particular attention to the area of the 5 flex beam bolt hole locations. If a crack is found, replace the unairworthy hub with an airworthy hub before further flight. Report the finding to the Los Angeles Aircraft Certification Office within 10 days of finding the crack.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Within 4 hours time-in-service
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
MD Helicopters, Inc. Model MD900 helicopters with part numbers 900R2101008-103, -105, and -107.
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
This document publishes in the Federal Register an amendment adopting Emergency Airworthiness Directive (AD) 2010-18-52 which was sent previously to all known owners and operators of MD Helicopters, Inc. (MDHI) Model MD900 helicopters by individual letters. This AD requires visually inspecting the main rotor hub (hub) for a crack. If a crack is found, this AD requires, before further flight, replacing the unairworthy hub with an airworthy hub. Additionally, if a cracked hub is found, this AD requires reporting the finding to the Los Angeles Aircraft Certification Office within 10 days of finding the crack. This AD is prompted by two reports of cracks detected in the hub in the area near the flex beam bolt hole locations during maintenance on two MDHI Model MD900 helicopters. The actions specified by this AD are intended to detect a crack in the hub and prevent failure of the hub and subsequent loss of control of the helicopter.
Document Text
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[Federal Register Volume 75, Number 220 (Tuesday, November 16, 2010)]
[Rules and Regulations]
[Pages 69862-69864]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2010-28456]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2010-1126; Directorate Identifier 2010-SW-078-AD;
Amendment 39-16515; AD 2010-18-52]
RIN 2120-AA64
Airworthiness Directives; MD Helicopters, Inc. Model MD900
Helicopters
AGENCY: Federal Aviation Administration, DOT.
ACTION: Final rule; request for comments.
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SUMMARY: This document publishes in the Federal Register an amendment
adopting Emergency Airworthiness Directive (AD) 2010-18-52 which was
sent previously to all known owners and operators of MD Helicopters,
Inc. (MDHI) Model MD900 helicopters by individual letters. This AD
requires visually inspecting the main rotor hub (hub) for a crack. If a
crack is found, this AD requires, before further flight, replacing the
unairworthy hub with an airworthy hub. Additionally, if a cracked hub
is found, this AD requires reporting the finding to the Los Angeles
Aircraft Certification Office within 10 days of finding the crack. This
AD is prompted by two reports of cracks detected in the hub in the area
near the flex beam bolt hole locations during maintenance on two MDHI
Model MD900 helicopters. The actions specified by this AD are intended
to detect a crack in the hub and prevent failure of the hub and
subsequent loss of control of the helicopter.
DATES: Effective December 1, 2010, to all persons except those persons
to whom it was made immediately effective by Emergency AD 2010-18-52,
issued on August 23, 2010, which contained the requirements of this
amendment.
Comments for inclusion in the Rules Docket must be received on or
before January 18, 2011.
ADDRESSES: Use one of the following addresses to submit comments on
this AD:
<bullet> Federal eRulemaking Portal: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the instructions for submitting comments.
<bullet> Fax: 202-493-2251.
<bullet> Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590.
<bullet> Hand Delivery: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
You may get the service information identified in this AD from MD
Helicopters, Inc., 4555 East McDowell Road, Mesa, Arizona 85215-9734,
USA, telephone (480) 346-6300 or (800) 388-3378, fax (480) 346-6813, or
at <a href="/cdn-cgi/l/email-protection#1c6f796e6a757f7979727b757279796e75727b5c7178747970757f736c68796e6f327f7371"><span class="__cf_email__" data-cfemail="1a697f686c73797f7f747d73747f7f6873747d5a777e727f767379756a6e7f686934797577">[email protected]</span></a>.
Examining the Docket: You may examine the docket that contains the
AD, any comments, and other information on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a>, or in person at the Docket Operations office
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The Docket Operations office (telephone (800) 647-5527) is
located in Room W12-140 on the ground floor of the West Building at the
street address stated in the ADDRESSES section. Comments will be
available in the AD docket shortly after receipt.
FOR FURTHER INFORMATION CONTACT: Roger Durbin, Aviation Safety
Engineer, FAA, Los Angeles Aircraft Certification Office, Airframe
Branch, 3960 Paramount Blvd., Lakewood, California 90712, telephone
(562) 627-5233, fax (562) 627-5210.
SUPPLEMENTARY INFORMATION: On August 18, 2010, we issued Emergency AD
2010-18-51. That Emergency AD was prompted by two reports of cracks
detected in the hub in the area near the flex beam bolt hole locations
during
[[Page 69863]]
maintenance on two MDHI Model MD900 helicopters. That Emergency AD
required, within 4 hours time-in-service, visually inspecting the hub
for a crack, paying particular attention to the area of the 5 flex beam
bolt hole locations. If you found a crack, the Emergency AD 2010-18-51
required, before further flight, replacing the unairworthy hub with an
airworthy hub. If you found a cracked hub, the Emergency AD also
required, within 10 days of finding the crack, reporting the finding to
the Los Angeles Aircraft Certification Office.
After we issued Emergency AD 2010-18-51, we discovered that we used
part number (P/N) 900R2102008-103, -105, and -107, in the
``Applicability'' section of the AD, which is incorrect. The correct P/
N is 900R2101008-103, -105, and -107. Therefore, we superseded
Emergency AD 2010-18-51 with Emergency AD 2010-18-52. Emergency AD
2010-18-52 contains the same requirements as Emergency AD 2010-18-51
but corrects the P/N for the hub.
We have reviewed two letters issued by MDHI, dated August 11 and
August 16, 2010, recommending visual inspections, feedback from
operators, and diligence in conducting ``preflight inspections'' of the
hub. MDHI has received reports of two cracked hubs. The hubs were
returned to MDHI for evaluation, and MDHI is analyzing the cracked
hubs.
This unsafe condition is likely to exist or develop on other
helicopters of the same type design. Therefore, this AD requires,
within 4 hours time in service, visually inspecting the hub for a
crack, paying particular attention to the area of the 5 flex beam bolt
hole locations. If you find a crack, this AD requires, before further
flight, replacing the unairworthy hub with an airworthy hub. If you
find a cracked hub, this AD also requires, within 10 days of finding
the crack, reporting the finding to the Los Angeles Aircraft
Certification Office. This AD is an interim action pending the results
of an ongoing investigation to determine further corrective actions.
The short compliance time involved is required because the
previously described critical unsafe condition can adversely affect the
structural integrity and controllability of the helicopter. Therefore,
a visual inspection of the hub is required within 4 hours time-in-
service. If a crack is found, the unairworthy hub must be replaced with
an airworthy hub before further flight, and this AD must be issued
immediately.
Since it was found that immediate corrective action was required,
notice and opportunity for prior public comment thereon were
impracticable and contrary to the public interest, and good cause
existed to make the AD effective immediately by individual letters
issued on August 23, 2010 to all known U.S. owners and operators of
MDHI Model MD900 helicopters. These conditions still exist, and the AD
is hereby published in the Federal Register as an amendment to 14 CFR
39.13 to make it effective to all persons. However, we have added a
paragraph (c) to the AD to add information regarding the Paperwork
Reduction Act Burden Statement. We have determined that this change
neither increases the economic burden on any operator nor increases the
scope of the AD.
We estimate that this AD will affect 33 helicopters of U.S.
registry. The required inspection of the hub will take approximately 1
work hour per helicopter to accomplish at an average labor rate of $85
per work hour for a labor cost of $85 per helicopter. If a cracked hub
is found, it will take approximately 11 hours per helicopter to replace
the hub at an average labor rate of $85 per work hour for a labor cost
of $935 per helicopter. Therefore, it is estimated that the actions
required by this AD will require a total of 12 work hours per
helicopter for a total labor cost of $1,020. Required parts will cost
approximately $12,480 for each hub. Based on these figures, we estimate
the total cost impact of the AD on U.S. operators to be $29,635. This
estimation assumes that each affected helicopter is inspected and that
only two helicopters have a hub that is cracked and needs to be
replaced.
Comments Invited
This AD is a final rule that involves requirements that affect
flight safety and was not preceded by notice and an opportunity for
public comment; however, we invite you to submit any written data,
views, or arguments regarding this AD. Send your comments to an address
listed under ADDRESSES. Include ``Docket No. FAA-2010-1126; Directorate
Identifier 2010-SW-078-AD'' at the beginning of your comments. We
specifically invite comments on the overall regulatory, economic,
environmental, and energy aspects of the AD. We will consider all
comments received by the closing date and may amend the AD in light of
those comments.
We will post all comments we receive, without change, to <a href="http://www.regulations.gov">http://www.regulations.gov</a>, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact
with FAA personnel concerning this AD. Using the search function of our
docket Web site, you can find and read the comments to any of our
dockets, including the name of the individual who sent the comment. You
may review the DOT's complete Privacy Act Statement in the Federal
Register published on April 11, 2000 (65 FR 19477-78).
Regulatory Findings
We have determined that this AD will not have federalism
implications under Executive Order 13132. This AD will 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 above, I certify that the 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); and
3. 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 AD. See the AD docket to examine the economic evaluation.
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.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Safety.
Adoption of the Amendment
0
Accordingly, pursuant to the authority delegated to me by the
Administrator, the Federal Aviation Administration
[[Page 69864]]
amends part 39 of the Federal Aviation Regulations (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. Section 39.13 is amended by adding a new airworthiness directive to
read as follows:
2010-18-52 MD Helicopters, Inc.: Amendment 39-16515. Docket No. FAA-
2010-1126; Directorate Identifier 2010-SW-078-AD. Supersedes
Emergency AD 2010-18-51, Directorate Identifier 2010-SW-076-AD.
Applicability: Model MD900 helicopters, with lower main rotor
hub (hub), part number 900R2101008-103, -105, and -107, installed,
certificated in any category.
Compliance: Required as indicated, unless accomplished
previously.
To detect a crack in the hub and prevent the failure of the hub
and subsequent loss of control of the helicopter, do the following:
(a) Within 4 hours time-in-service, visually inspect the hub for
a crack, paying particular attention to the area of the 5 flex beam
bolt hole locations. If you find a crack, before further flight,
replace the hub with an airworthy hub.
(b) If you find a crack, within 10 days, report the finding to
Roger Durbin, Aviation Safety Engineer, FAA, Los Angeles Aircraft
Certification Office, Airframe Branch, e-mail <a href="/cdn-cgi/l/email-protection#0e5c61696b7c204a7b7c6c67604e686f6f20696178"><span class="__cf_email__" data-cfemail="95c7faf2f0e7bbd1e0e7f7fcfbd5f3f4f4bbf2fae3">[email protected]</span></a>
or fax (562) 627-5210.
(c) A federal agency may not conduct or sponsor, and a person is
not required to respond to, nor shall a person be subject to a
penalty for failure to comply with a collection of information
subject to the requirements of the Paperwork Reduction Act unless
that collection of information displays a current valid OMB Control
Number. The OMB Control Number for this information collection is
2120-0056. Public reporting for this collection of information is
estimated to be approximately 5 minutes per response, including the
time for reviewing instructions, completing and reviewing the
collection of information. All responses to this collection of
information are mandatory. Comments concerning the accuracy of this
burden and suggestions for reducing the burden should be directed to
the FAA at: 800 Independence Ave., SW., Washington, DC 20591, Attn:
Information Collection Clearance Officer, AES-200.
(d) To request a different method of compliance or a different
compliance time for this AD, follow the procedures in 14 CFR 39.19.
Contact the Manager, Los Angeles Aircraft Certification Office, FAA,
ATTN: Roger Durbin, Aviation Safety Engineer, Airframe Branch, 3960
Paramount Blvd., Lakewood, California 90712, telephone (562) 627-
5233, fax (562) 627-5210, for information about previously approved
alternative methods of compliance.
(e) The Joint Aircraft System/Component (JASC) Code is 6220:
Main Rotor Head.
(f) This amendment becomes effective on December 1, 2010, to all
persons except those persons to whom it was made immediately
effective by Emergency AD 2010-18-52, issued August 23, 2010, which
contained the requirements of this amendment.
Issued in Fort Worth, Texas, on November 5, 2010.
Lance T. Gant,
Acting Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2010-28456 Filed 11-15-10; 8:45 am]
BILLING CODE 4910-13-P
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