[Federal Register Volume 69, Number 133 (Tuesday, July 13, 2004)]
[Proposed Rules]
[Pages 41994-41997]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-15790]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2004-18582; Directorate Identifier 2003-NM-35-AD]
RIN 2120-AA64


Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. 
(EMBRAER) Model EMB-135 and -145 Series Airplanes

AGENCY: Federal Aviation Administration (FAA), DOT.

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ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain EMBRAER Model EMB-135 and -145 series airplanes. This 
proposed AD would require measuring the fillet radius dimension of the 
trunnion fitting webs of the wings; and reworking the fillet radius of 
the trunnion fitting web in order to increase the radius, doing related 
investigative actions, and doing applicable corrective action, if 
necessary. This proposed AD is prompted by a report indicating that 
trunnion fittings of the wings have been manufactured with a web fillet 
radius smaller than the minimum required by the design data, which may 
induce the occurrence of fatigue cracks at the root of the trunnion 
fillet radius and adjacent structures (e.g., spar and ribs). We are 
proposing this AD to detect and correct fatigue cracking of the wing 
trunnion fittings or adjacent structure, which could result in failure 
of the main landing gear, consequent damage to surrounding structure, 
and possible loss of control of the airplane during landing.

DATES: We must receive comments on this proposed AD by August 12, 2004.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide rulemaking Web site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street SW., Nassif Building, room PL-401, 
Washington, DC 20590.
     By fax: (202) 493-2251.
     Hand Delivery: room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street SW., Washington, DC, between 9 a.m. 
and 5 p.m., Monday through Friday, except Federal holidays.
    You can get the service information identified in this proposed AD 
from Empresa Brasileira de Aeronautica S.A. (EMBRAER), P.O. Box 343--
CEP 12.225, Sao Jose dos Campos--SP, Brazil.
    You may examine the contents of this AD docket on the Internet at 
http://dms.dot.gov, or at the Docket Management Facility, U.S. 
Department of Transportation, 400 Seventh Street SW., room PL-401, on 
the plaza level of the Nassif Building, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Todd Thompson, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-1175; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Docket Management System (DMS)

    The FAA has implemented new procedures for maintaining AD dockets 
electronically. As of May 17, 2004, new AD actions are posted on DMS 
and assigned a docket number. We track each action and assign a 
corresponding directorate identifier. The DMS AD docket number is in 
the form ``Docket No. FAA-2004-99999.'' The Transport Airplane 
Directorate identifier is in the form ``Directorate Identifier 2004-NM-
999-AD.'' Each DMS AD docket also lists the directorate identifier 
(``Old Docket Number'') as a cross-reference for searching purposes.

Comments Invited

    We invite you to submit any written relevant data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2004-18582; 
Directorate Identifier 2003-NM-35-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments submitted by the closing date and may amend the 
proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of our 
docket website, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You may review the DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
may visit http://dms.dot.gov.
    We are reviewing the writing style we currently use in regulatory 
documents. We are interested in your comments on whether the style of 
this document is clear, and your suggestions to improve the clarity of 
our communications that affect you. You can get more information about 
plain language at http://www.faa.gov/language and http://www.plainlanguage.gov.

Examining the Docket

    You may examine the AD docket in person at the Docket Management 
Facility office between 9 a.m. and 5 p.m., Monday through Friday, 
except Federal holidays. The Docket Management Facility office 
(telephone (800) 647-5227) is located on the plaza level of the Nassif 
Building at the DOT street address stated in the ADDRESSES section. 
Comments will be available in the AD docket shortly after the DMS 
receives them.

Discussion

    The Departmento de Aviacao Civil (DAC), which is the airworthiness 
authority for Brazil, notified us that an unsafe condition may exist on 
certain EMBRAER Model EMB-135 and -145 series airplanes. The DAC 
advises that the trunnion fittings of the wings have been manufactured 
with a Web fillet radius smaller than the minimum required by the 
design data. This may induce fatigue cracks at the root of the trunnion 
fillet radius and adjacent structures (e.g., spar and ribs). Such 
fatigue cracks, if not detected and corrected, could result in failure 
of the main landing gears (MLG), consequent damage to surrounding 
structure, and possible loss of control of the airplane during landing.

Relevant Service Information

    EMBRAER has issued Service Bulletin 145-57-0034, Change 01, dated 
January 9, 2002. The service bulletin describes procedures for 
measuring the fillet radius dimension of the trunnion fitting webs of 
the wings; and reworking the fillet radius of the trunnion fitting web 
in order to increase the radius, doing related investigative actions, 
and doing applicable corrective actions, if necessary. The related 
investigative action involves performing a dye-penetrant inspection on 
the reworked area for cracks. The applicable corrective actions involve 
contacting EMBRAER for technical disposition. We have determined that 
accomplishment of the actions specified in the service information will 
adequately address the unsafe condition. The DAC mandated the service 
information and issued Brazilian airworthiness directive 2001-12-03R1, 
effective February 4, 2002, to ensure the continued airworthiness of 
these airplanes in Brazil.

FAA's Determination and Requirements of the Proposed AD

    These airplane models are manufactured in Brazil and are type 
certificated for operation in the United States under the provisions of 
section 21.29 of the Federal Aviation

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Regulations (14 CFR 21.29) and the applicable bilateral airworthiness 
agreement. Pursuant to this bilateral airworthiness agreement, the DAC 
has kept the FAA informed of the situation described above. We have 
examined the DAC's findings, evaluated all pertinent information, and 
determined that AD action is necessary for products of this type design 
that are certificated for operation in the United States.
    Therefore, we are proposing this AD, which would require measuring 
the fillet radius dimension of the trunnion fitting webs of the wings; 
and reworking the fillet radius of the trunnion fitting web in order to 
increase the radius, doing related investigative actions, and doing 
applicable corrective actions, if necessary. The proposed AD would 
require you to use the service information described previously to 
perform these actions, except as discussed under ``Differences Between 
the Proposed AD and the Service Bulletin.''

Differences Between Proposed AD and Service Bulletin

    Operators should note that, although the service bulletin specifies 
that operators may contact the manufacturer for disposition of certain 
repair conditions, this proposed AD would require operators to repair 
those conditions in accordance with a method approved by either the FAA 
or the DAC (or its delegated agent). In light of the type of repair 
that would be required to address the unsafe condition, and consistent 
with existing bilateral airworthiness agreements, we have determined 
that, for this proposed AD, a repair approved by either the FAA or the 
DAC would be acceptable for compliance with this proposed AD.
    In addition, unlike the procedures described in the service 
bulletin, this proposed AD would not permit further flight if cracks 
are detected in the trunnion fitting of the main landing gear. We have 
determined that, because of the safety implications and consequences 
associated with such cracking, any cracked trunnion fitting must be 
repaired before further flight.

Costs of Compliance

    This proposed AD would affect about 60 airplanes of U.S. registry. 
The proposed measurement would take about 2 work hours per airplane, at 
an average labor rate of $65 per work hour. Based on these figures, the 
estimated cost of the proposed AD for U.S. operators is $7,800, or $130 
per airplane.

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. 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, 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 
airworthiness directive (AD):

Empresa Brasileira De Aeonautica S.A. (EMBRAER): Docket No. FAA-
2004-18582; Directorate Identifier 2003-NM-35-AD.

Comments Due Date

    (a) The Federal Aviation Administration must receive comments on 
this AD action by August 12, 2004.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to EMBRAER Model EMB-135 and -145 series 
airplanes, as listed in EMBRAER Service Bulletin 145-57-0034, Change 
01, dated January 9, 2002; certificated in any category.

Unsafe Condition

    (d) This AD was prompted by a report indicating that trunnion 
fittings of the wings have been manufactured with a web fillet 
radius smaller than the minimum required by the design data, which 
may induce the occurrence of fatigue cracks at the root of the 
trunnion fillet radius and adjacent structures (e.g., spar and 
ribs). We are issuing this AD to detect and correct fatigue cracking 
of the wing trunnion fittings or adjacent structure, which could 
result in failure of the main landing gear, consequent damage to 
surrounding structure, and possible loss of control of the airplane 
during landing.

Compliance

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

Service Bulletin

    (f) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of EMBRAER Service Bulletin 145-57-0034, 
Change 01, dated January 9, 2002.

Measurement

    (g) Before the accumulation of 2,000 total flight cycles, or 
within 500 flight hours after the effective date of this AD, 
whichever occurs later, measure the fillet radius dimension of the 
trunnion fitting webs of the wings in accordance with paragraph 
3.(C), ``Part I,'' of the service bulletin.
    (1) If the fillet radius value is equal to or greater than 
0.1969 inches (5 mm), no further action is required by this AD.
    (2) If a fillet radius value is less than 0.0394 inches (1 mm), 
before further flight, do the actions specified in paragraph (h) of 
this AD.
    (3) If the fillet radius value is equal to or greater than 
0.0394 inch (1 mm), but less than 0.1969 inch (5 mm), before the 
accumulation of 4,000 total flight cycles, or within 500 flight 
hours after the effective date of this AD, whichever occurs later, 
do the actions specified in paragraph (h) of this AD.

Rework and Further Corrective Actions, if Necessary

    (h) Rework the fillet radius of the trunnion fitting web to 
increase the radius, do related investigative actions, and do 
applicable corrective actions by accomplishing all the actions 
specified in paragraph 3.(D), ``Part II,'' of the service bulletin. 
Do the actions in accordance with the service bulletin, except as 
provided by paragraph (i) of this AD. Any applicable corrective 
actions must be done before further flight.
    (1) If the final fillet radius is less than 0.1969 inch (5 mm) 
and the radius limit contour is reached, before further flight, 
repair in accordance with a method approved by either the Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate; 
or the Departmento de Aviacao Civil (DAC) (or its delegated agent).
    (2) If the final fillet radius is equal to or greater than 
0.1969 inches (5 mm), before further flight, shot-peen the reworked 
area in

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accordance with paragraph 3.(E), ``Part III,'' of the service 
bulletin.
    (i) If any crack is found in the structure during the related 
investigative action required by paragraph (h) of this AD, before 
further flight, repair in accordance with either the Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate; 
or the DAC (or its delegated agent).

Credit for Previous Revisions of Service Bulletin

    (j) Except as provided by paragraphs (h)(1) and (i) of this AD, 
measurements and rework of the fillet radius done before the 
effective date of this AD in accordance with EMBRAER Service 
Bulletin 145-57-0034, dated October 11, 2001, are acceptable for 
compliance with the requirements of this AD.

Alternative Methods of Compliance (AMOC)

    (k) The Manager, International Branch, Transport Airplane 
Directorate, FAA, has the authority to approve AMOCs for this AD, if 
requested in accordance with the procedures found in 14 CFR 39.19.

Related Information

    (l) Brazilian airworthiness directive 2001-12-03R1, effective 
February 4, 2002, also addresses the subject of this AD.


    Issued in Renton, Washington, on July 6, 2004.
Kevin M. Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 04-15790 Filed 7-12-04; 8:45 am]
BILLING CODE 4910-13-P