94-2179. Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B Series Airplanes  

  • [Federal Register Volume 59, Number 21 (Tuesday, February 1, 1994)]
    [Unknown Section]
    [Page 0]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 94-2179]
    
    
    [[Page Unknown]]
    
    [Federal Register: February 1, 1994]
    
    
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    DEPARTMENT OF TRANSPORTATION
    14 CFR Part 39
    
    [Docket No. 93-NM-192-AD; Amendment 39-8813; AD 94-03-06]
    
     
    
    Airworthiness Directives; Saab Model SAAB SF340A and SAAB 340B 
    Series Airplanes
    
    AGENCY: Federal Aviation Administration, DOT.
    
    ACTION: Final rule; request for comments.
    
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    SUMMARY: This amendment adopts a new airworthiness directive (AD) that 
    is applicable to certain Saab Model SAAB SF340A and SAAB 340B series 
    airplanes. This action requires inspections to detect improper 
    connections of the wire harness installation to the nacelle fire 
    extinguisher, correction of any discrepancy found, and modification of 
    the wiring. This amendment is prompted by a report of improperly routed 
    control wiring to the nacelle fire extinguishers on a Model SAAB 340B 
    series airplane. The actions specified in this AD are intended to 
    prevent failure of the fire extinguishing agent to reach the correct 
    engine in the event of an engine fire.
    
    DATES: Effective on February 16, 1994.
        The incorporation by reference of certain publications listed in 
    the regulations is approved by the Director of the Federal Register as 
    of February 16, 1994.
        Comments for inclusion in the Rules Docket must be received on or 
    before April 4, 1994.
    
    ADDRESSES: Submit comments in triplicate to the Federal Aviation 
    Administration (FAA), Transport Airplane Directorate, ANM-103, 
    Attention: Rules Docket No. 93-NM-192-AD, 1601 Lind Avenue, SW., 
    Renton, Washington 98055-4056.
        The service information referenced in this AD 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; or at the 
    Office of the Federal Register, 800 North Capitol Street, NW., suite 
    700, Washington, DC.
    
    FOR FURTHER INFORMATION CONTACT: Mark Quam, Aerospace Engineer, 
    Standardization Branch, ANM-113, FAA, Transport Airplane Directorate, 
    1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (206) 
    227-2145; fax (206) 227-1320.
    
    SUPPLEMENTARY INFORMATION: The Luftfartsverket (LFV), which is the 
    airworthiness authority for Sweden, recently notified the FAA that an 
    unsafe condition may exist on certain Saab Model SAAB SF340A and SAAB 
    340B series airplanes. The LFV advises that improperly routed control 
    wiring to the nacelle fire extinguishers was found during a ``C check'' 
    inspection on a Model SAAB 340B series airplane. Further investigation 
    revealed that some airplanes have an excessively long wire harness, 
    which allows the possibility to incorrectly connect the wire harness to 
    the nacelle fire extinguisher cartridge. When the fire extinguisher 
    discharges, fire extinguishant transfers to the opposite nacelle fire 
    zone if a wire harness is incorrectly routed or connected. In such a 
    case, only one extinguisher, rather than two (as under normal 
    conditions), is available to extinguish a fire in the nacelle fire 
    zone. This condition, if not corrected, could result in failure of the 
    fire extinguishing agent to reach the correct engine in the event of an 
    engine fire.
        Saab has issued Service Bulletin 340-26-012, Revision 1, dated 
    October 5, 1993, that describes procedures for an inspection to detect 
    improper connections of the wire harness installation to the nacelle 
    fire extinguisher, correction of any discrepancy found, and 
    modification of the wiring. The modification involves shortening the 
    wires by making a loop and securing with wax string, as necessary. The 
    LFV classified this service bulletin as mandatory and issued Swedish 
    Airworthiness Directive SAD No. 1-059, dated September 13, 1993, in 
    order to assure the continued airworthiness of these airplanes in 
    Sweden.
        This airplane model is manufactured in Sweden and is type 
    certificated for operation in the United States under the provisions of 
    Section 21.29 of the Federal Aviation Regulations 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.
        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, this AD is being issued to prevent failure of the 
    fire extinguishing agent to reach the correct engine in the event of an 
    engine fire. This AD requires an inspection to detect improper 
    connections of the wire harness installation to the nacelle fire 
    extinguisher, correction of any discrepancy found, and modification of 
    the wiring. The actions are required to be accomplished in accordance 
    with the service bulletin described previously.
        Since a situation exists that requires the immediate adoption of 
    this regulation, it is found that notice and opportunity for prior 
    public comment hereon are impracticable, and that good cause exists for 
    making this amendment effective in less than 30 days.
    Comments Invited
        Although this action is in the form of a final rule that involves 
    requirements affecting flight safety and, thus, was not preceded by 
    notice and an opportunity for public comment, comments are invited on 
    this rule. Interested persons are invited to comment on this 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 under the caption ADDRESSES. All 
    communications received on or before the closing date for comments will 
    be considered, and this rule may be amended in light of the comments 
    received. Factual information that supports the commenter's ideas and 
    suggestions is extremely helpful in evaluating the effectiveness of the 
    AD action and determining whether additional rulemaking action would be 
    needed.
        Comments are specifically invited on the overall regulatory, 
    economic, environmental, and energy aspects of the rule that might 
    suggest a need to modify the 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 that 
    summarizes each FAA-public contact concerned with the substance of this 
    AD 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 93-NM-192-AD.'' The postcard will be date stamped and 
    returned to the commenter.
        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.
        The FAA has determined that this regulation is an emergency 
    regulation that must be issued immediately to correct an unsafe 
    condition in aircraft, and is not a ``significant regulatory action'' 
    under Executive Order 12866. It has been determined further that this 
    action involves an emergency regulation under DOT Regulatory Policies 
    and Procedures (44 FR 11034, February 26, 1979). If it is determined 
    that this emergency regulation otherwise would be significant under DOT 
    Regulatory Policies and Procedures, a final regulatory evaluation will 
    be prepared and placed in the Rules Docket. A copy of it, if filed, 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 
    Administrator, the Federal Aviation Administration amends 14 CFR part 
    39 of the Federal Aviation Regulations as follows:
    
    PART 39--AIRWORTHINESS DIRECTIVES
    
        I. The authority citation for part 39 continues to read as follows:
    
        Authority: 49 U.S.C. App. 1354(a), 1421 and 1423; 49 U.S.C. 
    106(g); and 14 CFR 11.89.
    
    
    Sec. 39.13  [Amended]
    
        2. Section 39.13 is amended by adding the following new 
    airworthiness directive:
    
    94-03-06 SAAB AIRCRAFT AB: Amendment 39-8813. Docket 93-NM-192-AD.
    
        Applicability: Model SAAB SF340A series airplanes, serial 
    numbers 004 through 159 inclusive; and Model SAAB 340B, serial 
    numbers 160 through 345 inclusive; certificated in any category.
        Compliance: Required as indicated, unless accomplished 
    previously.
        To preclude cross-connection of the wire harness installation to 
    the engine nacelle fire extinguisher, accomplish the following:
        (a) Within 25 days after the effective date of this AD, perform 
    an inspection to ensure proper connections of the wire harness 
    installation to the nacelle fire extinguisher, in accordance with 
    Saab Service Bulletin 340-26-012, Revision 1, dated October 5, 1993. 
    Prior to further flight, correct any discrepancy found and modify 
    the wiring, in accordance with the service bulletin.
        (b) Repeat the inspection specified in paragraph (a) of this AD 
    immediately following any maintenance action during which both 
    electric connectors to either of the fire extinguishers in the 
    nacelle electrical bays are disconnected.
        (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, Standardization Branch, ANM-113, 
    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, 
    Standardization Branch, ANM-113.
    
        Note: Information concerning the existence of approved 
    alternative methods of compliance with this AD, if any, may be 
    obtained from the Standardization Branch, ANM-113.
    
        (d) Special flight permits may be issued in accordance with FAR 
    21.197 and 21.199 to operate the airplane to a location where the 
    requirements of this AD can be accomplished.
        (e) The inspections shall be done in accordance with Saab 
    Service Bulletin 340-26-012, Revision 1, dated October 5, 1993. 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 Saab Aircraft AB, SAAB Aircraft 
    Product Support, S-581.88, Linkoping, Sweden. Copies may be 
    inspected at the FAA, Transport Airplane Directorate, 1601 Lind 
    Avenue, SW., Renton, Washington; or at the Office of the Federal 
    Register, 800 North Capitol Street, NW., suite 700, Washington, DC.
        (f) This amendment becomes effective on February 16, 1994.
    
        Issued in Renton, Washington, on January 26, 1994.
    James V. Devany,
    Acting Manager, Transport Airplane Directorate, Aircraft Certification 
    Service.
    [FR Doc. 94-2179 Filed 1-31-94; 8:45 am]
    BILLING CODE 4910-13-U
    
    
    

Document Information

Effective Date:
2/16/1994
Published:
02/01/1994
Department:
Transportation Department
Entry Type:
Uncategorized Document
Action:
Final rule; request for comments.
Document Number:
94-2179
Dates:
Effective on February 16, 1994.
Pages:
0-0 (1 pages)
Docket Numbers:
Federal Register: February 1, 1994, Docket No. 93-NM-192-AD, Amendment 39-8813, AD 94-03-06
CFR: (1)
14 CFR 39.13