[Federal Register Volume 65, Number 79 (Monday, April 24, 2000)]
[Proposed Rules]
[Pages 21677-21679]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-10163]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2000-NM-25-AD]
RIN 2120-AA64


Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Saab Model SAAB SF340A and 
SAAB 340B series airplanes. This proposal would require a one-time 
inspection to detect chafing of the wires and harnesses in the cabin 
compartment ceiling; repair, if necessary; and installation of 
protective sleeving. This proposal is prompted by issuance of mandatory 
continuing airworthiness information by a foreign civil airworthiness 
authority. The actions specified by the proposed AD are intended to 
prevent false warnings of a hot engine exhaust tailpipe and 
intermittent signal failure, which could result in the consequent 
execution of unnecessary procedures by the flightcrew.

DATES: Comments must be received by May 24, 2000.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 2000-NM-25-AD, 1601 Lind Avenue, SW., 
Renton, Washington 98055-4056. Comments may be inspected at this 
location between 9:00 a.m. and 3:00 p.m., Monday through Friday, except 
Federal holidays.
    The service information referenced in the proposed rule may be 
obtained from Saab Aircraft AB, SAAB Aircraft Product Support, S-
581.88, Linkoping, Sweden. This information may be examined at the FAA, 
Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, 
Washington.

FOR FURTHER INFORMATION CONTACT: Norman B. Martenson, Manager, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

[[Page 21678]]

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 2000-NM-25-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 2000-NM-25-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Luftfartsverket (LFV), which is the airworthiness authority for 
Sweden, notified the FAA that an unsafe condition may exist on certain 
Saab Model SAAB SF340A and SAAB 340B series airplanes. The LFV advises 
that there has been one reported false warning indicating the engine 
exhaust tailpipe was hot. The warning was caused by chafed wires 
located in the cabin compartment ceiling. Those wires are routed 
through the lightening holes of the airframe. The chafing was found 
between the wires and the edge (edge string) of the lightening holes. 
The LFV further advised of two additional occurrences of similar 
chafing. Such false warnings could result in unnecessary procedures 
executed by the flightcrew.

Explanation of Relevant Service Information

    Saab has issued Service Bulletin 340-92-027, dated December 10, 
1999, which describes procedures for a one-time inspection to detect 
chafing of the wires and harnesses in the cabin compartment ceiling. 
The service bulletin describes procedures for repair of certain 
chafing. The service bulletin further describes procedures for the 
installation of protective sleeving on all of the harnesses routed in 
the inspection area. Accomplishment of the actions specified in the 
service bulletin is intended to adequately address the identified 
unsafe condition. The LFV classified this service bulletin as mandatory 
and issued Swedish airworthiness directive 1-149, dated December 10, 
1999, in order to ensure the continued airworthiness of these airplanes 
in Sweden.

FAA's Conclusions

    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. The FAA has examined the findings of the 
LFV, reviewed all available information, and determined that AD action 
is necessary for products of this type design that are certificated for 
operation in the United States.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other airplanes of the same type design registered 
in the United States, the proposed AD would require accomplishment of 
the actions specified in the service bulletin described previously, 
except as discussed below.

Differences Between Proposed Rule and Relevant Service Information

    Operators should note that, although the service bulletin specifies 
that the manufacturer may be contacted for disposition of certain 
repair conditions, this proposal would require the repair of those 
conditions to be accomplished in accordance with a method approved by 
either the FAA, or the LFV (or its delegated agent). In light of the 
type of repair that would be required to address the identified unsafe 
condition, and in consonance with existing bilateral airworthiness 
agreements, the FAA has determined that, for this proposed AD, a repair 
approved by either the FAA or the LFV would be acceptable for 
compliance with this proposed AD.

Cost Impact

    The FAA estimates that 288 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 36 work 
hours per airplane to accomplish the proposed actions, and that the 
average labor rate is $60 per work hour. Required parts for the 
sleeving installation would cost approximately $358 per airplane. Based 
on these figures, the cost impact of the proposed AD on U.S. operators 
is estimated to be $725,184, or $2,518 per airplane.
    The cost impact figure discussed above is based on assumptions that 
no operator has yet accomplished any of the proposed requirements of 
this AD action, and that no operator would accomplish those actions in 
the future if this AD were not adopted.

Regulatory Impact

    The regulations proposed herein 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. Therefore, it 
is determined that this proposal would not have federalism implications 
under Executive Order 13132.
    For the reasons discussed above, I certify that 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) if promulgated, 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 copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
part 39 of the Federal Aviation Regulations (14 CFR part 39) as 
follows:

[[Page 21679]]

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:

Saab Aircraft AB: Docket 2000-NM-25-AD.

    Applicability: Model SAAB SF340A, serial numbers -004 through -
159 inclusive; and SAAB 340B series airplanes, serial numbers -160 
through -459 inclusive; 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 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 false warning of a hot engine exhaust tailpipe and 
intermittent signal failure, the consequent execution of unnecessary 
procedures by the flightcrew, accomplish the following:
    (a) Prior to the accumulation of 14,000 total flight hours, or 
within 4,000 flight hours after the effective date of this AD, 
whichever occurs later: Perform a detailed visual inspection to 
detect chafing of the wires and harnesses in the cabin compartment 
ceiling, and install protective sleeving on all of the harnesses 
routed in the inspection area; in accordance with Saab Service 
Bulletin 340-92-027, dated December 10, 1999. Except as provided by 
paragraph (b) of this AD, prior to further flight, repair any 
chafing in accordance with the service bulletin.

    Note 2: For the purposes of this AD, a detailed visual 
inspection is defined as: ``An intensive visual examination of a 
specific structural area, system, installation, or assembly to 
detect damage, failure, or irregularity. Available lighting is 
normally supplemented with a direct source of good lighting at 
intensity deemed appropriate by the inspector. Inspection aids such 
as mirror, magnifying lenses, etc., may be used. Surface cleaning 
and elaborate access procedures may be required.''

    (b) For any chafing detected during the inspection required by 
paragraph (a) of this AD for which the service bulletin specifies to 
contact Saab for appropriate action: Prior to further flight, repair 
in accordance with a method approved by the Manager, International 
Branch, ANM-116, FAA, Transport Airplane Directorate; or the 
Luftfartsverket (LFV) (or its delegated agent). For a repair method 
to be approved by the Manager, International Branch, ANM-116, as 
required by this paragraph, the Manager's approval letter must 
specifically reference this AD.

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, International Branch, ANM-116, FAA, 
Transport 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, International 
Branch, ANM-116.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

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.

    Note 4: The subject of this AD is addressed in Swedish 
airworthiness directive 1-149, dated December 10, 1999.



    Issued in Renton, Washington, on April 18, 2000.
Donald L. Riggin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 00-10163 Filed 4-21-00; 8:45 am]
BILLING CODE 4910-13-U