AD Amdt-39-11253

[Federal Register Volume 64, Number 159 (Wednesday, August 18, 1999)]
[Rules and Regulations]
[Pages 44819-44821]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 99-20880]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-233-AD; Amendment 39-11253; AD 99-17-04]
RIN 2120-AA64


Airworthiness Directives; Empresa Brasileira de Aeronautica S.A. 
(EMBRAER) Model EMB-120 Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain EMBRAER Model EMB-120 series airplanes, that 
requires replacement of the fairlead support assemblies of the aileron 
control cable located in the nacelle outboard fittings with new, 
improved assemblies; and replacement of certain attachment screws with 
new screws. This amendment also provides an option for performing 
repetitive inspections until accomplishment of the replacement. This 
amendment is prompted by reports of aileron cable wear due to chafing 
found between the aileron control cables and nylon grommets. The 
actions specified by this AD are intended to prevent such chafing, 
which could result in failure of the aileron cables, and consequent 
reduced controllability of the airplane.

DATES: Effective September 22, 1999.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of September 22, 1999.

ADDRESSES: The service information referenced in this AD may be 
obtained from Empresa Brasileira de Aeronautica S.A. (EMBRAER), P.O. 
Box 343--CEP 12.225, Sao Jose dos Campos--SP, Brazil. This information 
may be examined at the Federal Aviation Administration (FAA), Transport 
Airplane Directorate, Rules Docket, 1601 Lind Avenue, SW., Renton, 
Washington; or at the FAA, Small Airplane Directorate, Atlanta Aircraft 
Certification Office, One Crown Center, 1895 Phoenix Boulevard, suite 
450, Atlanta, Georgia; or at the Office of the Federal Register, 800 
North Capitol Street, NW, suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT: Rob Capezutto, Aerospace Engineer, 
Systems and Flight Test Branch, ACE-116A, FAA, Small Airplane 
Directorate, Atlanta Aircraft Certification Office, One Crown Center, 
1895 Phoenix Boulevard, suite 450, Atlanta, Georgia 30349; telephone 
(770) 703-6071; fax (770) 703-6097.

SUPPLEMENTARY INFORMATION: A proposal to amend part 39 of the Federal 
Aviation Regulations (14 CFR part 39) to include an airworthiness 
directive (AD) that is applicable to certain EMBRAER Model EMB-120 
series airplanes was published in the Federal Register on September 3, 
1998 (63 FR 46932). That action proposed to require replacement of the 
fairlead support assemblies of the aileron control cable located in the 
nacelle outboard fittings with new, improved assemblies; and 
replacement of certain attachment screws with new screws.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the comments received.

Support for the Proposal

    One commenter supports the proposed rule.

Request To Withdraw Proposed Rule

    Two commenters state that the proposed rule is not warranted and 
cannot be justified. One commenter, an operator, does not agree that 
this is a safety of flight issue and states that the proposed AD does 
not specify the amount of wear found on the cables, or that the cables 
were in danger of, or close to, failure. In support of withdrawal of 
the proposed rule, the commenter references two instances, one in 1991 
and one in 1997, in which the Brazilian Centro Tocnico Aeroespacial 
(CTA) documented that if a single cable failed during flight, the 
airplane would be able to land safely. The commenter also states that 
the EMB-120 Maintenance Review Board (MRB) inspection interval for the 
aileron cables is sufficient to ensure continued airworthiness in lieu 
of issuance of the final rule.
    Another commenter, the manufacturer, states that inspections of 
certain airplanes conducted at its facility revealed cables with 
polished areas, but no indication of wear or rupture was detected. The 
commenter states also that operators that have not incorporated 
Revision 2 of the service bulletin have a rigorous inspection interval 
of every 400 flight hours, per the MRB. For operators that have 
incorporated Revision 2 of the service bulletin, the cable inspections 
are to be accomplished at each ``5A'' check (2,000 flight hours). The 
commenter states that during the past 10 years it has performed 25 
``C'' checks with no record of aileron cable replacement due to broken 
wires.
    The FAA does not concur with the commenters' requests. The FAA does 
consider this a safety issue based on the determination that if the 
aileron cable were to break during a critical portion of the flight, 
such as during a steep turn or on approach for landing, it would result 
in reduced controllability of the airplane.
    In addition, an investigation of service difficulties conducted by 
the FAA revealed over 200 reports of aileron cable wear. Although most 
of these occurred in the early 1990's, several cases were reported in 
1997 and two through mid-1998. This suggests that not all operators are 
incorporating the service bulletin.
    Based on this information, the FAA finds that issuance of the final 
rule is necessary to ensure an adequate level of safety for the 
affected fleet.

Request To Revise Inspection Intervals

    One commenter states that Parts I, II, and III of EMBRAER Service 
Bulletin 120-27-0068, Change 02, dated March 20, 1998, include a 
statement referring to MRB Tasks 27-07 and 27-65 [the correct reference 
as stated in the service bulletin is Maintenance Planning Guide (MPG) 
Tasks 27-07 and 27-64] for inspection intervals of the specified areas, 
both pre- and post-mod. The commenter requests that the inspection 
interval of the post-mod installation be based on an analysis of 
inspection

[[Page 44820]]

findings and an agreement between the operator and its Principal 
Maintenance Inspector (PMI).
    The FAA does not concur with the commenter's request. The FAA finds 
that, at this time, insufficient data exist to support allowing PMI's 
to make an assessment of aileron cable wear in order to increase the 
regular post-mod inspection intervals called out in the MPG. The FAA 
may, however, approve a request for an adjustment of the post-mod 
inspection intervals if data are submitted to substantiate that such an 
adjustment would provide an equivalent level of safety.

Request To Extend Compliance Time and Add Repetitive Inspections

    One commenter requests that the FAA extend the proposed compliance 
time for the modification from within 400 hours time-in-service after 
the effective date of this AD, to within 500 hours time-in-service 
after the effective date of this AD. The commenter also requests that 
if the FAA proceeds with issuing this AD, inspections of the aileron 
cables be added; the inspections should be accomplished at intervals 
not to exceed 500 flight hours until installation of the modification. 
The commenter indicates that accomplishment of the modification cannot 
be completed within 400 hours time-in-service due to lack of 
availability of the kits used for the modification. The commenter 
states that one-third of the compliance time will be used waiting for 
delivery of the kits.
    The FAA partially concurs with the commenter's request. The FAA has 
determined that allowing repetitive inspections of the aileron cables 
at intervals not to exceed 500 flight hours ``until installation of the 
modification'' is not appropriate in this case because it allows the 
inspections to continue indefinitely, which does not address the unsafe 
condition in a timely manner. However, the manufacturer has stated that 
parts kits are available 90 days after submission of the purchase 
request. In light of the time required to obtain the parts, the FAA 
agrees to revise the compliance time for accomplishment of the 
modification, and to add an option for repetitive inspections in 
accordance with procedures specified in the airplane maintenance 
manual. The FAA finds that repetitive inspections of the aileron cable 
at intervals not to exceed 400 hours time-in-service until 
accomplishment of the modification, for a time period not to exceed 6 
months after the effective date of this AD, will not adversely affect 
safety, and will allow the modification to be performed at a base 
during regularly scheduled maintenance where special equipment and 
trained maintenance personnel will be available if necessary. The 
Summary section, as well as paragraphs (a) and (b) of this final rule, 
have been revised accordingly.

Explanation of Change to Proposal

    The FAA has added ``Note 2'' to the final rule to clarify the 
definition of a general visual inspection.

Conclusion

    After careful review of the available data, including the comments 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule with the changes described 
previously. The FAA has determined that these changes will neither 
increase the economic burden on any operator nor increase the scope of 
the AD.

Cost Impact

    The FAA estimates that 227 airplanes of U.S. registry will be 
affected by this AD.
    For airplanes identified in Part I of EMBRAER Service Bulletin 120-
27-0068, Change 02, it will take approximately 4 work hours per 
airplane to accomplish the required replacement of the fairlead support 
assemblies of the aileron control cable, at an average labor rate of 
$60 per work hour. Required parts will cost approximately $1,464 per 
airplane. Based on these figures, the cost impact of this replacement 
required by this AD on U.S. operators is estimated to be $386,808, or 
$1,704 per airplane.
    For airplanes identified in Part II of EMBRAER Service Bulletin 
120-27-0068, Change 02, it will take approximately 1 work hour per 
airplane to accomplish the required replacement of the fairlead support 
assemblies of the aileron control cable, at an average labor rate of 
$60 per work hour. Required parts will cost approximately $1,292 per 
airplane. Based on these figures, the cost impact of this replacement 
required by this AD on U.S. operators is estimated to be $306,904, or 
$1,352 per airplane.
    For airplanes identified in Part III of EMBRAER Service Bulletin 
120-27-0068, Change 02, it will take approximately 1 work hour per 
airplane to accomplish the required replacement of the fairlead support 
assemblies of the aileron control cable, at an average labor rate of 
$60 per work hour. Required parts will cost approximately $501 per 
airplane. Based on these figures, the cost impact of this replacement 
required by this AD on U.S. operators is estimated to be $127,347, or 
$561 per airplane.
    For airplanes identified in Part IV of EMBRAER Service Bulletin 
120-27-0068, Change 02, it will take approximately 1 work hour per 
airplane to accomplish the required replacement of the attachment 
screws, at an average labor rate of $60 per work hour. Required parts 
cost will be minimal. Based on these figures, the cost impact of this 
replacement required by this AD on U.S. operators is estimated to be 
$13,620, or $60 per airplane.
    The cost impact figures discussed above are based on assumptions 
that no operator has yet accomplished any of the requirements of this 
AD action, and that no operator would accomplish those actions in the 
future if this AD were not adopted.
    Should an operator elect to accomplish the optional repetitive 
inspections provided by this AD action, it would take approximately 2 
work hours per airplane, per inspection cycle, to accomplish, at an 
average labor rate of $60 per work hour. Based on these figures, the 
cost impact of the inspections would be $60 per airplane, per 
inspection cycle.

Regulatory Impact

    The regulations adopted herein will not have substantial direct 
effects 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. Therefore, in 
accordance with Executive Order 12612, it is determined that this final 
rule does not have sufficient federalism implications to warrant the 
preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this action (1) Is 
not a ``significant regulatory action'' under Executive Order 12866; 
(2) is not a ``significant rule'' under 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. A final evaluation has been prepared for this action 
and it is contained in the Rules Docket. A copy of it may be obtained 
from the Rules Docket at the location provided under the caption 
ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the

[[Page 44821]]

Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (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. Section 39.13 is amended by adding the following new 
airworthiness directive:

99-17-04 Empresa Brasileira de Aeronautica S.A. (Embraer): Amendment 
39-11253. Docket 98-NM-233-AD.

    Applicability: Model EMB-120 series airplanes, as listed in 
EMBRAER Service Bulletin 120-27-0068, Change 02, dated March 20, 
1998, certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been otherwise 
modified, altered, or repaired so that the performance of the 
requirements of this AD is affected, the owner/operator must request 
approval for an alternative method of compliance in accordance with 
paragraph (c) of this AD. The request should include an assessment 
of the effect of the modification, alteration, or repair on the 
unsafe condition addressed by this AD; and, if the unsafe condition 
has not been eliminated, the request should include specific 
proposed actions to address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent chafing between the aileron control cables and nylon 
grommets, which could result in failure of the aileron cables, and 
consequent reduced controllability of the airplane, accomplish the 
following:
    (a) Within 400 hours time-in-service after the effective date of 
this AD, accomplish the requirements of either paragraph (a)(1) or 
(a)(2) of this AD.

Repetitive Inspections

    (1) Perform a general visual inspection to detect chafing between 
the aileron control cables and nylon grommets, in accordance with the 
procedures specified in EMBRAER EMB-120 Airplane Maintenance Manual, 
Chapters 20-20-01, 27-00-01, and 27-11-00.
    (i) If any chafing is detected, prior to further flight, 
accomplish the requirements of paragraph (b) of this AD.
    (ii) If no chafing is detected: Repeat the inspection thereafter 
at intervals not to exceed 400 hours time-in-service until the 
requirements of paragraph (b) of this AD have been accomplished.

General Visual Inspection

    Note 2: For the purposes of this AD, a general visual inspection 
is defined as: ``A visual examination of an interior or exterior 
area, installation or assembly to detect obvious damage, failure, or 
irregularity. This level of inspection is made under normally 
available lighting conditions such as daylight, hangar lighting, 
flashlight, or drop-light and may require removal or opening of 
access panels or doors. Stands, ladders, or platforms may be 
required to gain proximity to the area being checked.''

    (2) Accomplish the requirements of paragraph (b) of this AD.

Replacement

    (b) Except as provided by paragraph (a)(2) of this AD: Within 6 
months after the effective date of this AD, accomplish the 
requirements of paragraph (b)(1), (b)(2), (b)(3), or (b)(4) of this 
AD, as applicable, in accordance with EMBRAER Service Bulletin 120-
27-0068, Change 02, dated March 20, 1998. Accomplishment of the 
requirements of this paragraph constitutes terminating action for 
the repetitive inspections specified in paragraph (a)(1) of this AD.
    (1) For airplanes having serial numbers 120003, 120004, and 
120006 through 120217 inclusive, on which the modification specified 
in EMBRAER Service Bulletin 120-27-0068, dated February 28, 1991, 
has not been accomplished: Replace the fairlead support assemblies 
of the aileron control cable (provided with fairleads in both Teflon 
and nylon) located in the nacelle outboard fittings with new, 
improved assemblies (Part I), in accordance with the service 
bulletin.
    (2) For airplanes having serial numbers 120003, 120004, and 
120006 through 120217 inclusive, on which the modification specified 
in EMBRAER Service Bulletin 120-27-0068, dated February 28, 1991, 
has been accomplished; and airplanes having serial numbers 120218 
through 120331 inclusive: Replace the fairlead support assemblies of 
the aileron control cable (provided with fairleads in Teflon) 
located in the nacelle outboard fittings with new, improved 
assemblies (Part II), in accordance with the service bulletin.
    (3) For airplanes having serial numbers 120003, 120004, and 
120006 through 120331 inclusive, on which the modification specified 
in EMBRAER Service Bulletin 120-27-0068, dated February 28, 1991, or 
Change 01, dated August 1, 1997, has been accomplished; and 
airplanes having serial numbers 120332 and 120333: Replace the 
attachment screws and the fairlead support assemblies of the aileron 
control cable with new, improved assemblies (Part III), in 
accordance with the service bulletin.
    (4) For airplanes having serial numbers 120334, 120335, and 
120336: Replace the attachment screws of the fairlead support 
assemblies of the aileron control cable (Part IV), in accordance 
with the service bulletin.

Alternative Methods of Compliance

    (c) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Atlanta Aircraft Certification 
Office (ACO), FAA, Small Airplane Directorate. Operators shall 
submit their requests through an appropriate FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Atlanta ACO.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Atlanta ACO.

Special Flight Permits

    (d) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished.

Incorporation by Reference

    (e) The replacement shall be done in accordance with EMBRAER 
Service Bulletin 120-27-0068, Change 02, dated March 20, 1998. This 
incorporation by reference was approved by the Director of the 
Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 
51. Copies may be obtained from Empresa Brasileira de Aeronautica 
S.A. (EMBRAER), P.O. Box 343--CEP 12.225, Sao Jose dos Campos--SP, 
Brazil. Copies may be inspected at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW, Renton, Washington; or FAA, Small 
Airplane Directorate, Atlanta Aircraft Certification Office, One 
Crown Center, 1895 Phoenix Boulevard, Suite 450, Atlanta, Georgia; 
or at the Office of the Federal Register, 800 North Capitol Street, 
NW, suite 700, Washington, DC.
    (f) This amendment becomes effective on September 22, 1999.

    Issued in Renton, Washington, on August 6, 1999.
D.L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 99-20880 Filed 8-17-99; 8:45 am]
BILLING CODE 4910-13-P