[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 [www.gpo.gov]
[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
