[Federal Register: October 27, 2004 (Volume 69, Number 207)]
[Proposed Rules]
[Page 62625-62627]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr27oc04-20]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2004-19447; Directorate Identifier 2004-NM-97-AD]
RIN 2120-AA64
Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B
Series Airplanes
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD)
for all Saab Model SAAB SF340A and SAAB 340B series airplanes. This
proposed AD would require a one-time inspection to determine the part
and serial numbers of certain molded assembly engine mounts (isolators)
and the cure dates of certain bonded canister assemblies incorporated
in those engine mounts; and related corrective actions if necessary.
This proposed AD is prompted by a report that disbonding of the
elastomer from the inner metal core and shim of certain molded assembly
engine mounts has occurred within a few hundred hours of operation,
causing heavy chafing of the engine support system and chafing of the
fire sensor loop. We are proposing this AD to prevent reduced integrity
of the fire-shielding capacity of the nacelle structure and a possible
fire detector fault.
DATES: We must receive comments on this proposed AD by November 26,
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.
For service information identified in this proposed AD, contact
Saab Aircraft AB, SAAB Aircraft Product Support, S-581.88,
Link[ouml]ping, Sweden.
You can 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:
Technical information: Dan Rodina, Aerospace Engineer,
International Branch, ANM-116, FAA, Transport Airplane Directorate,
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425)
227-2125; fax (425) 227-1149.
Plain language information: Marcia Walters, marcia.walters@faa.gov.
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 relevant written data, views, or
arguments regarding this proposed AD. Send your comments to an address
listed under ADDRESSES. Include ``Docket No. FAA-2004-19447;
Directorate Identifier 2004-NM-97-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 Web site, 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 can review the DOT's complete Privacy Act Statement in the
Federal Register published on April 11, 2000 (65 FR 19477-78), or you
can 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 can examine the AD docket on the Internet at http://dms.dot.gov
, or 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 Luftfartsverket (LFV), which is the airworthiness authority for
Sweden,
[[Page 62626]]
notified us that an unsafe condition may exist on all Saab Model SAAB
SF340A and SAAB 340B series airplanes. The LFV advises that disbonding
of the elastomer from the inner metal core and shim of the bonded
canister assemblies incorporated in certain molded assembly engine
mounts (isolators) has occurred within a few hundred hours of
operation. This disbonding could reduce the redundancy and change the
stiffness and damping characteristics of the engine support system,
cause heavy chafing of the nacelle structure, and cause chafing of the
fire sensor loop. This condition, if not corrected, could result in
reduced integrity of the fire-shielding capacity of the nacelle
structure and a possible fire detector fault.
Relevant Service Information
Saab has issued Saab Service Bulletin 340-71-059, dated May 16,
2003. The service bulletin describes procedures for a one-time
inspection to determine the part and serial numbers of certain molded
assembly engine mounts (isolators) and the cure dates of certain bonded
canister assemblies incorporated in those engine mounts; an inspection
for chafing of the nacelle structure of all airplanes and for chafing
of the fire sensor loop of certain airplanes; and related corrective
actions if necessary. Corrective actions include replacement of the
engine mounts and repair or replacement of chafed nacelle structure and
fire sensor loop components. Accomplishing the actions specified in the
service information is intended to adequately address the unsafe
condition. The LFV mandated the service information and issued Swedish
airworthiness directive SAD 1-192, dated May 16, 2003, to ensure the
continued airworthiness of these airplanes in Sweden.
Service Bulletin 340-71-059 refers to Barry Controls Service Letter
93948-71-05, dated April 30, 2003, as an additional source of service
information for determining the part numbers and serial numbers of
certain molded assembly engine mounts, and the cure dates of the bonded
canister assemblies incorporated in those engine mounts.
FAA's Determination and Requirements of the Proposed AD
These airplane models are manufactured in Sweden and are type
certificated for operation in the United States under the provisions of
section 21.29 of the Federal Aviation Regulations (14 CFR 21.29) and
the applicable bilateral airworthiness agreement. Pursuant to this
bilateral airworthiness agreement, the LFV has kept the FAA informed of
the situation described above. We have examined the LFV's findings,
evaluated all pertinent information, and determined that we need to
issue an AD for products of this type design that are certificated for
operation in the United States.
Therefore, we are proposing this AD, which would require a one-time
inspection to determine the part and serial numbers of certain molded
assembly engine mounts (isolators) and the cure dates of the bonded
canister assemblies incorporated in those engine mounts; a general
visual inspection for chafing of certain elements adjacent to those
engine mounts; and related corrective actions if necessary. The
proposed AD would require you to use Saab Service Bulletin 340-71-059
described previously to perform these actions, except as discussed
under ``Clarification of Inspection Terminology.''
Clarification of Inspection Terminology
Saab Service Bulletin 340-71-059 specifies an inspection for
chafing of certain elements adjacent to certain molded assembly engine
mounts. To eliminate any confusion about this inspection, this proposed
AD would require a general visual inspection of those elements. Note 2
of this proposed AD includes a definition of this type of inspection.
Costs of Compliance
This proposed AD would affect about 170 airplanes of U.S. registry.
The proposed actions 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 this proposed AD for U.S. operators is $22,100 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):
SAAB Aircraft AB: Docket No. FAA-2004-19447; Directorate Identifier
2004-NM-97-AD.
Comments Due Date
(a) The Federal Aviation Administration must receive comments on
this AD action by November 26, 2004.
Affected ADs
(b) None.
Applicability
(c) This AD applies to all Model SAAB SF340A and SAAB 340B
series airplanes, certificated in any category.
Unsafe Condition
(d) This AD was prompted by a report that disbonding of the
elastomer from the inner metal core and shim of certain molded
assembly engine mounts (isolators) has occurred within a few hundred
hours of operation, causing heavy chafing of the engine support
system and chafing of the fire sensor loop. We are issuing this AD
to prevent reduced integrity of the fire-shielding capacity of the
engine nacelle structure and a possible fire detector fault.
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.
Inspection
(f) Within 500 flight hours after the effective date of this AD,
perform a one-time inspection to determine the part and serial
numbers of certain molded assembly engine mounts (isolators) and the
cure dates of certain bonded canister assemblies incorporated in
those engine mounts; and a general visual inspection for chafing of
the
[[Page 62627]]
nacelle structure and fire sensor loop; and related corrective
actions, as applicable; in accordance with the Accomplishment
Instructions of Saab Service Bulletin 340-71-059, dated May 16,
2003. Corrective actions must be accomplished prior to further
flight.
Note 1: Saab Service Bulletin 340-71-059 refers to Barry
Controls Service Letter 93948-71-05, dated April 30, 2003, as an
additional source of service information.
Note 2: For the purposes of this AD, a general visual inspection
is ``a visual examination of a interior or exterior area,
installation or assembly to detect obvious damage, failure or
irregularity. This level of inspection is made from within touching
distance unless otherwise specified. A mirror may be necessary to
ensure visual access to all surfaces in the inspection area. This
level of inspection is made under normal available lighting
conditions such as daylight, hangar lighting, flashlight or
droplight 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.''
Alternative Methods of Compliance (AMOCs)
(g) The Manager, International Branch, ANM-116, 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
(h) Swedish airworthiness directive SAD 1-192, dated May 16,
2003, also addresses the subject of this AD.
Issued in Renton, Washington, on October 18, 2004.
Kalene C. Yanamura,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 04-24034 Filed 10-26-04; 8:45 am]
BILLING CODE 4910-13-P