
[Federal Register: March 31, 2008 (Volume 73, Number 62)]
[Proposed Rules]
[Page 16790-16792]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr31mr08-26]


[[Page 16790]]

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0369; Directorate Identifier 2008-CE-015-AD]
RIN 2120-AA64


Airworthiness Directives; British Aerospace Regional Aircraft
Model HP. 137 Jetstream MK 1, Jetstream Series 200, 3100, and 3200
Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the
products listed above. This proposed AD results from mandatory
continuing airworthiness information (MCAI) originated by an aviation
authority of another country to identify and correct an unsafe
condition on an aviation product. The MCAI describes the unsafe
condition as:

    A failure mode has been identified following the examination of
parts from another aircraft type (Jetstream 4100 series) that can
lead to the loss of a nose-wheel. The Jetstream (HP.137) Mk1, 200,
3100 and 200 series use a similar method for retaining the wheel
assemblies on the landing gear axle and can therefore experience the
same type of failure, i.e. a combination of excessive wear and/or
adverse tolerances on the axle inner cone, outer cone or wheel hub
splined sleeve cones resulting in the loss of the critical gap
between the inner flange face of the wheel outer cone and the axle
end face. If this gap is lost, it results in the wheel having free
play along the length of the axle. This condition, if not corrected,
can cause the wheel nut lock plate to break, leading to the wheel
retention nut unscrewing and subsequent separation of the nose wheel
from the landing gear axle.

    The proposed AD would require actions that are intended to address
the unsafe condition described in the MCAI.

DATES: We must receive comments on this proposed AD by April 30, 2008.

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://
www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     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.
     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.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://
www.regulations.gov; or in person at the Docket Management Facility
between 9 a.m. and 5 p.m., Monday through Friday, except Federal
holidays. The AD docket contains this proposed AD, the regulatory
evaluation, any comments received, and other information. The street
address for the Docket Office (telephone (800) 647-5527) is in the
ADDRESSES section. Comments will be available in the AD docket shortly
after receipt.

FOR FURTHER INFORMATION CONTACT: Taylor Martin, Aerospace Engineer,
FAA, Small Airplane Directorate, 901 Locust, Room 301, Kansas City,
Missouri 64106; telephone: (816) 329-4138; fax: (816) 329-4090.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or
arguments about this proposed AD. Send your comments to an address
listed under the ADDRESSES section. Include ``Docket No. FAA-2008-0369;
Directorate Identifier 2008-CE-015-AD'' at the beginning of your
comments. We specifically invite comments on the overall regulatory,
economic, environmental, and energy aspects of this proposed AD. We
will consider all comments received by the closing date and may amend
this proposed AD because of those comments.
    We will post all comments we receive, without change, to http://
www.regulations.gov, including any personal information you provide. We
will also post a report summarizing each substantive verbal contact we
receive about this proposed AD.

Discussion

    The European Aviation Safety Agency (EASA), which is the Technical
Agent for the Member States of the European Community, has issued AD
No: 2008-0037, dated February 22, 2008 (referred to after this as ``the
MCAI''), to correct an unsafe condition for the specified products. The
MCAI states:

    A failure mode has been identified following the examination of
parts from another aircraft type (Jetstream 4100 series) that can
lead to the loss of a nose-wheel. The Jetstream (HP.137) Mk1, 200,
3100 and 3200 series use a similar method for retaining the wheel
assemblies on the landing gear axle and can therefore experience the
same type of failure, i.e. a combination of excessive wear and/or
adverse tolerances on the axle inner cone, outer cone or wheel hub
splined sleeve cones resulting in the loss of the critical gap
between the inner flange face of the wheel outer cone and the axle
end face. If this gap is lost, it results in the wheel having free
play along the length of the axle. This condition, if not corrected,
can cause the wheel nut lock plate to break, leading to the wheel
retention nut unscrewing and subsequent separation of the nose wheel
from the landing gear axle.
    For the reasons described above, this AD requires repetitive
inspections of the nose landing gear to ensure that the wheels are
correctly retained and, depending on findings, replacement of worn
parts.

You may obtain further information by examining the MCAI in the AD
docket.

Relevant Service Information

    British Aerospace Regional Aircraft has issued British Aerospace
Jetstream Series 3100 and 3200 Service Bulletin 32-JA070241, dated July
13, 2007. The actions described in this service information are
intended to correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of the Proposed AD

    This product has been approved by the aviation authority of another
country, and is approved for operation in the United States. Pursuant
to our bilateral agreement with this State of Design Authority, they
have notified us of the unsafe condition described in the MCAI and
service information referenced above. We are proposing this AD because
we evaluated all information and determined the unsafe condition exists
and is likely to exist or develop on other products of the same type
design.

Differences Between This Proposed AD and the MCAI or Service
Information

    We have reviewed the MCAI and related service information and, in
general, agree with their substance. But we might have found it
necessary to use different words from those in the MCAI to ensure the
AD is clear for U.S. operators and is enforceable. In making these
changes, we do not intend to differ substantively from the information
provided in the MCAI and related service information.
    We might also have proposed different actions in this AD from those
in the MCAI in order to follow FAA policies. Any such differences are
highlighted in a NOTE within the proposed AD.

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Costs of Compliance

    We estimate that this proposed AD will affect 190 products of U.S.
registry. We also estimate that it would take about 1 work-hour per
product to comply with the basic requirements of this proposed AD. The
average labor rate is $80 per work-hour.
    Based on these figures, we estimate the cost of the proposed AD on
U.S. operators to be $15,200, or $80 per product.
    In addition, we estimate that any necessary follow-on actions would
take about 1 work-hour and require parts costing $250, for a cost of
$330 per product. We have no way of determining the number of products
that may need these actions.

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 above, 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); 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 a regulatory 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, 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 adding the following new AD:

British Aerospace Regional Aircraft: Docket No. FAA-2008-0369;
Directorate Identifier 2008-CE-015-AD.

Comments Due Date

    (a) We must receive comments by April 30, 2008.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Model HP. 137 Jetstream MK 1, Jetstream
Series 200, 3100, and 3200 airplanes, all serial numbers,
certificated in any category.

Subject

    (d) Air Transport Association of America (ATA) Code 32: Landing
Gear.

Reason

    (e) The mandatory continuing airworthiness information (MCAI)
states:
    A failure mode has been identified following the examination of
parts from another aircraft type (Jetstream 4100 series) that can
lead to the loss of a nose wheel. The Jetstream (HP.137) Mk1, 200,
3100 and 3200 series use a similar method for retaining the wheel
assemblies on the landing gear axle and can therefore experience the
same type of failure, i.e. a combination of excessive wear and/or
adverse tolerances on the axle inner cone, outer cone or wheel hub
splined sleeve cones resulting in the loss of the critical gap
between the inner flange face of the wheel outer cone and the axle
end face. If this gap is lost, it results in the wheel having free
play along the length of the axle. This condition, if not corrected,
can cause the wheel nut lock plate to break, leading to the wheel
retention nut unscrewing and subsequent separation of the nose wheel
from the landing gear axle.
    For the reasons described above, this AD requires repetitive
inspections of the nose landing gear to ensure that the wheels are
correctly retained and, depending on findings, replacement of worn
parts.

Actions and Compliance

    (f) Unless already done, do the following actions:
    (1) Within the next 3 months after the effective date of this
AD, initially inspect the left and right nose wheel attachments to
the axle following British Aerospace Jetstream Series 3100 and 3200
Service Bulletin 32-JA070241, dated July 13, 2007.
    (2) Repetitively thereafter inspect the left and right nose
wheel attachments to the axle at the intervals specified in Table 1
of this AD following British Aerospace Jetstream Series 3100 and
3200 Service Bulletin 32-JA070241, dated July 13, 2007. If during
any repetitive inspection the gap measurement changes from the
previous inspection measurement, adjust the repetitive inspection
interval as necessary based on Table 1 of this AD.

                Table 1.--Repetitive Inspection Intervals
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                                            Then repetitively inspect at
       If the measured gap size is:           the following intervals:
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0.002 to 0.005 inches (0.05 to 0.13 mm)...  Within 500 hours TIS.
More than 0.005 to 0.010 inches (0.13 to    Within 1,000 hours TIS.
 0.25 mm).
More than 0.010 to 0.020 inches (0.25 to    Within 2,000 hours TIS.
 0.51 mm).
More than 0.020 inches (0.51 mm)..........  Within 3,000 hours TIS.
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    (3) Before further flight, if during any of the inspections
required in paragraphs (f)(1) or (f)(2) of this AD you find the gap
between the inner flange of the outer cone and the axle end face is
less than 0.002 inches (0.05 mm), replace all worn parts.

    Note 1: Replacement of parts does not constitute terminating
action for the inspection requirements of this AD.

FAA AD Differences

    Note 2: This AD differs from the MCAI and/or service information
as follows: No differences.

Other FAA AD Provisions

    (g) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager,
Standards Office, FAA, has the authority to approve AMOCs for this
AD, if requested using the procedures found in 14 CFR 39.19. Send
information to ATTN: Taylor Martin, Aerospace Engineer, FAA, Small
Airplane Directorate, 901 Locust, Room 301, Kansas City, Missouri
64106; telephone: (816) 329-4138; fax: (816) 329-4090. Before using
any approved AMOC on any airplane to which the AMOC applies, notify
your appropriate principal inspector (PI) in the FAA Flight
Standards District Office (FSDO), or lacking a PI, your local FSDO.
    (2) Airworthy Product: For any requirement in this AD to obtain
corrective actions from a manufacturer or other source, use these

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actions if they are FAA-approved. Corrective actions are considered
FAA-approved if they are approved by the State of Design Authority
(or their delegated agent). You are required to assure the product
is airworthy before it is returned to service.
    (3) Reporting Requirements: For any reporting requirement in
this AD, under the provisions of the Paperwork Reduction Act (44
U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has
approved the information collection requirements and has assigned
OMB Control Number 2120-0056.

Related Information

    (h) Refer to MCAI European Aviation Safety Agency (EASA) AD No:
2008-0037, dated February 22, 2008; and British Aerospace Jetstream
Series 3100 and 3200 Service Bulletin 32-JA070241, dated July 13,
2007, for related information.

    Issued in Kansas City, Missouri, on March 21, 2008.
David R. Showers,
Acting Manager, Small Airplane Directorate, Aircraft Certification
Service.
 [FR Doc. E8-6509 Filed 3-28-08; 8:45 am]

BILLING CODE 4910-13-P
