
[Federal Register: June 4, 2010 (Volume 75, Number 107)]
[Proposed Rules]               
[Page 31731-31734]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr04jn10-20]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0548; Directorate Identifier 2010-NM-041-AD]
RIN 2120-AA64

 
Airworthiness Directives; Bombardier, Inc. Model BD-700-1A10 and 
BD-700-1A11 Airplanes

AGENCY: Federal Aviation Administration (FAA), 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:


[[Page 31732]]


    Following five reported cases of balance washer screw failure on 
similar RATs [ram air turbines]/air driven generators installed on 
other aircraft types, an investigation * * * determined that a 
specific batch of the screws had a metallographic non-conformity 
that increased their susceptibility to brittle fracture. * * *
    Failure of a balance washer screw can result in loss of the 
related balance washer, with consequent turbine imbalance. Such 
imbalance could potentially result in RAT structural failure 
(including blade failure), loss of RAT electrical power and 
structural damage to the aircraft and, if deployment was activated 
by a dual engine shutdown, could also result in loss of hydraulic 
power for the flight controls [and consequent reduced ability of the 
flightcrew to maintain the safe flight and landing of the airplane].
* * * * *

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 July 19, 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 W12-40, 1200 New 
Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday 
through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Bombardier, Inc., 400 C[ocirc]te-Vertu Road West, Dorval, Qu[eacute]bec 
H4S 1Y9, Canada; telephone 514-855-5000; fax 514-855-7401; e-mail 
thd.crj@aero.bombardier.com; Internet http://www.bombardier.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 Operations office 
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 Operations 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: Christopher Alfano, Aerospace 
Engineer, Airframe and Mechanical Systems Branch, ANE-171, FAA, New 
York Aircraft Certification Office, 1600 Stewart Avenue, Suite 410, 
Westbury, New York 11590; telephone (516) 228-7340; fax (516) 794-5531.

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-2010-0548; 
Directorate Identifier 2010-NM-041-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 based on those comments.
    We have lengthened the 30-day comment period for proposed ADs that 
address MCAI originated by aviation authorities of other countries to 
provide adequate time for interested parties to submit comments. The 
comment period for these proposed ADs is now typically 45 days, which 
is consistent with the comment period for domestic transport ADs.
    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

    Transport Canada Civil Aviation (TCCA), which is the aviation 
authority for Canada, has issued Canadian Airworthiness Directive CF-
2010-01, dated January 18, 2010 (referred to after this as ``the 
MCAI''), to correct an unsafe condition for the specified products. The 
MCAI states:

    Following five reported cases of balance washer screw failure on 
similar RATs [ram air turbine]/air driven generators installed on 
other aircraft types, an investigation by Hamilton Sundstrand 
determined that a specific batch of the screws had a metallographic 
non-conformity that increased their susceptibility to brittle 
fracture. Subsequently, it was established that 187 RATs [Part 
Number (P/N) GL456-1101-7 and Hamilton Sundstrand P/Ns in the 762826 
series] had non-conforming screws installed either during production 
or possibly during maintenance or repair at Hamilton Sundstrand 
repair stations.
    Failure of a balance washer screw can result in loss of the 
related balance washer, with consequent turbine imbalance. Such 
imbalance could potentially result in RAT structural failure 
(including blade failure), loss of RAT electrical power and 
structural damage to the aircraft and, if deployment was activated 
by a dual engine shutdown, could also result in loss of hydraulic 
power for the flight controls [and consequent reduced ability of the 
flightcrew to maintain the safe flight and landing of the airplane].
    This [Canadian] directive mandates checking of the RAT and 
replacing the balance washer screws, if required. It also prohibits 
future installation of unmodified RATs.

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

Relevant Service Information

    Bombardier has issued Service Bulletins 700-24-075 and 700-1A11-24-
014, both Revision 01, both dated July 15, 2009. The actions described 
in this service information are intended to correct the unsafe 
condition identified in the MCAI.

FAA's Determination and Requirements of This 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 the State of Design Authority, we have 
been notified of the unsafe condition described in the MCAI and service 
information referenced above. We are proposing this AD because we 
evaluated all pertinent information and determined an unsafe condition 
exists and is likely to exist or develop on other products of the same 
type design.

Differences Between This 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.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would

[[Page 31733]]

affect about 115 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 $85 per 
work-hour. Based on these figures, we estimate the cost of the proposed 
AD on U.S. operators to be $9,775, or $85 per product.

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, 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 adding the following new AD:

Bombardier, Inc.: Docket No. FAA-2010-0548; Directorate Identifier 
2010-NM-041-AD.

Comments Due Date

    (a) We must receive comments by July 19, 2010.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Bombardier, Inc. Model BD-700-1A10 and 
BD-700-1A11 airplanes, serial numbers 9002 and subsequent; 
certificated in any category.

Subject

    (d) Air Transport Association (ATA) of America Code 24: 
Electrical power.

Reason

    (e) The mandatory continuing airworthiness information (MCAI) 
states:

    Following five reported cases of balance washer screw failure on 
similar RATs [ram air turbines]/air driven generators installed on 
other aircraft types, an investigation by Hamilton Sundstrand 
determined that a specific batch of the screws had a metallographic 
non-conformity that increased their susceptibility to brittle 
fracture. Subsequently, it was established that 187 RATs [Part 
Number (P/N) GL456-1101-7 and Hamilton Sundstrand P/Ns in the 762826 
series] had non-conforming screws installed either during production 
or possibly during maintenance or repair at Hamilton Sundstrand 
repair stations.
    Failure of a balance washer screw can result in loss of the 
related balance washer, with consequent turbine imbalance. Such 
imbalance could potentially result in RAT structural failure 
(including blade failure), loss of RAT electrical power and 
structural damage to the aircraft and, if deployment was activated 
by a dual engine shutdown, could also result in loss of hydraulic 
power for the flight controls [and consequent reduced ability of the 
flightcrew to maintain the safe flight and landing of the airplane].
    This [Canadian] directive mandates checking of the RAT and 
replacing the balance washer screws, if required. It also prohibits 
future installation of unmodified RATs.

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.

Inspection

    (g) For airplanes having serial numbers 9002 through 9380 
inclusive: At the earliest of the times identified in paragraphs 
(g)(1), (g)(2), (g)(3) and (g)(4) of this AD, inspect to determine 
the serial number of the installed ram air turbine (RAT), in 
accordance with the Accomplishment Instructions of the applicable 
service bulletin listed in Table 1 of this AD. This inspection may 
be conducted visually, which requires lowering the RAT. A review of 
airplane maintenance records is acceptable in lieu of this 
inspection if the serial number of the RAT can be conclusively 
determined from that review.
    (1) Within 500 flight hours or 24 months after the effective 
date of this AD, whichever occurs first; or
    (2) Prior to the next in-flight or on-ground functional test of 
the RAT, whichever occurs first after the effective date of this AD; 
or
    (3) Prior to the next in-flight or on-ground operational test of 
the RAT, whichever occurs first after the effective date of this AD; 
or
    (4) Prior to the next scheduled RAT in-flight deployment.
    (h) If the RAT serial number, as determined in paragraph (g) of 
this AD, is not listed in paragraph 1.A of the applicable service 
bulletin listed in Table 1 of this AD, no further action is required 
by this AD, except for paragraph (j) of this AD.

                                           Table 1--Service Bulletins
----------------------------------------------------------------------------------------------------------------
                                           Bombardier Service
                Model--                        Bulletin--           Revision--                Dated--
----------------------------------------------------------------------------------------------------------------
BD-700-1A11...........................  700-1A11-24-014.........              01  July 15, 2009.
BD-700-1A10...........................  700-24-075..............              01  July 15, 2009.
----------------------------------------------------------------------------------------------------------------

    (i) If the RAT serial number, determined in paragraph (g) of 
this AD, is listed in paragraph 1.A. of the applicable service 
bulletin listed in Table 1 of this AD, before further flight, 
inspect to determine if the symbol ``24-7'' is marked on the RAT 
identification plate, in accordance with the Accomplishment 
Instructions of the applicable service bulletin listed in Table 1

[[Page 31734]]

of this AD. A review of airplane maintenance records is acceptable 
in lieu of this inspection if the symbol ``24-7'' mark can be 
conclusively determined from that review.
    (1) If the symbol ``24-7'' is marked on the RAT identification 
plate, the balance washer screws have already been replaced and no 
further action is required by this AD, except for paragraph (j) of 
this AD.
    (2) If the symbol ``24-7'' is not marked on the RAT 
identification plate, before further flight, replace all balance 
washer screws with new balance washer screws, part number MS24667-
14, and mark the RAT identification plate with the symbol ``24-7,'' 
in accordance with the Accomplishment Instructions of the applicable 
service bulletin listed in Table 1 of this AD.
    (j) For all airplanes: As of the effective date of this AD, no 
person may install on any airplane a replacement or spare RAT (P/N 
GL456-1101-7; Hamilton Sundstrand P/Ns in the 762826 series) having 
one of the S/Ns listed in paragraph 1.A. of the applicable service 
bulletin listed in Table 1 of this AD unless the balance washer 
screws have already been replaced and the symbol ``24-7'' is marked 
on the RAT identification plate.

FAA AD Differences

    Note 1: This AD differs from the MCAI and/or service information 
as follows:
    Although Canadian Airworthiness Directive CF-2010-01, dated 
January 18, 2010, recommends accomplishing the visual inspection 
prior to the next scheduled in-flight operational test of the RAT, 
we have determined that interval would not address the identified 
unsafe condition soon enough to ensure an adequate level of safety 
for the affected fleet in light of the degree of urgency associated 
with the subject unsafe condition. This difference has been 
coordinated with Transport Canada Civil Aviation (TCCA).

Other FAA AD Provisions

    (k) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, New 
York Aircraft Certification Office (ACO), ANE-170, 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: Program 
Manager, Continuing Operational Safety, FAA, New York ACO, 1600 
Stewart Avenue, Suite 410, Westbury, New York 11590; telephone 516-
228-7300; fax 516-794-5531. 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.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer or other source, use these 
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

    (l) Refer to MCAI Transport Canada Civil Aviation (TCCA) 
Airworthiness Directive CF-2010-01, dated January 18, 2010; and 
Bombardier Service Bulletins 700-24-075, Revision 01, dated July 15, 
2009, and 700-1A11-24-014, Revision 01, dated July 15, 2009; for 
related information.

    Issued in Renton, Washington, on May 28, 2010.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-13419 Filed 6-3-10; 8:45 am]
BILLING CODE 4910-13-P

