
[Federal Register: June 28, 2010 (Volume 75, Number 123)]
[Proposed Rules]               
[Page 36577-36579]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr28jn10-16]                         

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Proposed Rules
                                                Federal Register
________________________________________________________________________

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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[[Page 36577]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0554; Directorate Identifier 2010-NM-082-AD]
RIN 2120-AA64

 
Airworthiness Directives; McDonnell Douglas Corporation Model MD-
90-30 Airplanes

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

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to supersede an existing airworthiness 
directive (AD) that applies to certain Model MD-90-30 airplanes. The 
existing AD currently requires modifying the auxiliary hydraulic power 
system (including doing all applicable related investigative and 
corrective actions). This proposed AD would require these same actions, 
using corrected service information. This proposed AD results from fuel 
system reviews conducted by the manufacturer, as well as reports of 
electrically shorted wires in the right wheel well and evidence of 
arcing on the auxiliary hydraulic pump power cables, which are routed 
within the tire burst area. We are proposing this AD to prevent 
electrically shorted wires or arcing at the auxiliary hydraulic pump 
power cables, which could result in a fire in the wheel well. We are 
also proposing this AD to reduce the potential of an ignition source 
adjacent to the fuel tanks, which, in combination with flammable fuel 
vapors, could result in a fuel tank explosion and consequent loss of 
the airplane.

DATES: We must receive comments on this proposed AD by August 12, 2010.

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.
    For service information identified in this proposed AD, contact 
Boeing Commercial Airplanes, Attention: Data & Services Management, 
3855 Lakewood Boulevard, MC D800-0019, Long Beach, California 90846-
0001; telephone 206-544-5000, extension 2; fax 206-766-5683; e-mail 
dse.boecom@boeing.com; Internet https://www.myboeingfleet.com. You may 
review copies of the referenced service information at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington. For information on the availability of this material at the 
FAA, call 425-227-1221.

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: Ken Sujishi, Aerospace Engineer, Cabin 
Safety/Mechanical and Environmental Systems Branch, ANM-150L, FAA, Los 
Angeles Aircraft Certification Office, 3960 Paramount Boulevard, 
Lakewood, California 90712-4137; telephone (562) 627-5353; fax (562) 
627-5210.

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-2010-0554; 
Directorate Identifier 2010-NM-082-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

    On March 18, 2009, we issued AD 2009-07-04, Amendment 39-15863 (74 
FR 14460, March 31, 2009), for certain Model MD-90-30 airplanes. That 
AD requires modifying the auxiliary hydraulic power system (including 
doing all applicable related investigative and corrective actions). 
That AD resulted from fuel system reviews conducted by the 
manufacturer, as well as reports of shorted wires in the right wheel 
well and evidence of arcing on the power cables of the auxiliary 
hydraulic pump. Boeing analysis determined that the existing auxiliary 
hydraulic pump wire harness assembly is routed within the tire burst 
area and that installing and routing a new and longer auxiliary 
hydraulic pump wire harness assembly outside the tire burst area will 
minimize the possibility of chafing and electrical wire arcing damage. 
We issued that AD to prevent shorted wires or electrical arcing at the 
auxiliary hydraulic pump, which could result in a fire in the wheel 
well; and to reduce the potential of an ignition source adjacent to the 
fuel tanks, which, in combination with flammable fuel vapors, could 
result in a fuel tank explosion and consequent loss of the airplane.

Actions Since Existing AD Was Issued

    Since we issued AD 2009-07-04, we have been advised that the Work 
Instructions of Boeing Alert Service Bulletin MD90-29A021, Revision 1, 
dated August 29, 2008 (the service bulletin referenced in AD 2009-07-
04), are inadequate in that some wire

[[Page 36578]]

support clamp orientations would present a riding condition with 
surrounding structure or existing hydraulic lines.

Relevant Service Information

    Boeing has issued Alert Service Bulletin MD90-29A021, Revision 2, 
dated March 16, 2010, which includes additional work (e.g., checking 
electrical resistance and doing a general visual inspection of the wire 
harness protective sleeving dimensions, which are related investigative 
actions; and installing new sleeving, adding tie tape, installing a new 
wire harness assembly, and installing new clamps, which are corrective 
actions).

FAA's Determination and Requirements of the Proposed AD

    We have evaluated all pertinent information and identified an 
unsafe condition that is likely to develop on other airplanes of the 
same type design. For this reason, we are proposing this AD, which 
would supersede AD 2009-07-04 but would not retain the requirements of 
the existing AD. This proposed AD would require accomplishing the 
actions specified in Boeing Alert Service Bulletin MD90-29A021, 
Revision 2, dated March 16, 2010, as described previously.

Costs of Compliance

    There are about 109 airplanes of the affected design in the 
worldwide fleet. The following table provides the estimated costs for 
U.S. operators to comply with this proposed AD.

                                                                     Estimated Costs
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                                       Number  of
                                                             Average                                                     U.S.-
              Action                      Work hours        labor rate          Parts            Cost per airplane     registered        Fleet cost
                                                             per hour                                                  airplanes
--------------------------------------------------------------------------------------------------------------------------------------------------------
Modification......................  Between 4 and 11.....          $85  Up to $4,870.........  Between $5,210 and              21  Between $109,410 and
                                                                                                $5,805.                             $121,905.
--------------------------------------------------------------------------------------------------------------------------------------------------------

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 have 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 that the 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. See the 
ADDRESSES section for a location to examine the regulatory evaluation.

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 Amendment 39-15863 (74 FR 
14460, March 31, 2009) and adding the following new AD:

McDonnell Douglas Corporation: Docket No. FAA-2010-0554; Directorate 
Identifier 2010-NM-082-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by August 
12, 2010.

Affected ADs

    (b) This AD supersedes AD 2009-07-04, Amendment 39-15863.

Applicability

    (c) This AD applies to McDonnell Douglas Corporation Model MD-
90-30 airplanes, certificated in any category; as identified in 
Boeing Alert Service Bulletin MD90-29A021, Revision 2, dated March 
16, 2010.

Subject

    (d) Air Transport Association (ATA) of America Code 29: 
Hydraulic Power.

Unsafe Condition

    (e) This AD results from fuel system reviews conducted by the 
manufacturer, as well as reports of electrically shorted wires in 
the right wheel well and evidence of arcing on the auxiliary 
hydraulic pump power cables, which are routed within the tire burst 
area. The Federal Aviation Administration is proposing this AD to 
prevent electrically shorted wires or arcing at the auxiliary 
hydraulic pump power cables, which could result in a fire in the 
wheel well. We are also proposing this AD to reduce the potential of 
an ignition source adjacent to the fuel tanks, which, in combination 
with flammable fuel vapors, could result in a fuel tank explosion 
and consequent loss of the airplane.

Compliance

    (f) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Replacement

    (g) Within 18 months after the effective date of this AD, modify 
the auxiliary hydraulic power system, and do all applicable related 
investigative and corrective actions, in accordance with the 
Accomplishment Instructions of Boeing Alert Service Bulletin MD90-
29A021, Revision 2, dated March 16, 2010. Do all applicable

[[Page 36579]]

related investigative and corrective actions before further flight.

Alternative Methods of Compliance (AMOCs)

    (h)(1) The Manager, Los Angeles Aircraft Certification 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: Ken Sujishi, Aerospace Engineer, Cabin Safety/Mechanical and 
Environmental Systems Branch, ANM-150L, FAA, Los Angeles Aircraft 
Certification Office, 3960 Paramount Boulevard, Lakewood, California 
90712-4137; telephone (562) 627-5353; fax (562) 627-5210.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your principal maintenance inspector (PMI) or 
principal avionics inspector (PAI), as appropriate, or lacking a 
principal inspector, your local Flight Standards District Office. 
The AMOC approval letter must specifically reference this AD.

    Issued in Renton, Washington, on June 17, 2010.
Robert D. Breneman,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-15652 Filed 6-25-10; 8:45 am]
BILLING CODE 4910-13-P

