[Federal Register Volume 63, Number 79 (Friday, April 24, 1998)]
[Rules and Regulations]
[Pages 20299-20300]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-10478]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 97-NM-263-AD; Amendment 39-10483; AD 98-09-04]
RIN 2120-AA64


Airworthiness Directives; Aerospatiale Model ATR72 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 Aerospatiale Model ATR72 series airplanes, that 
requires a one-time high frequency eddy current inspection to detect 
cracking of the lower fuselage structure, and repair, if necessary. 
This amendment also requires modification of certain fastener holes in 
the lower fuselage structure. This amendment is prompted by issuance of 
mandatory continuing airworthiness information by a foreign civil 
airworthiness authority. The actions specified by this AD are intended 
to prevent reduced structural integrity of the airplane due to fatigue 
cracking in the lower fuselage structure.

DATES: Effective May 29, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of May 29, 1998.

ADDRESSES: The service information referenced in this AD may be 
obtained from Aerospatiale, 316 Route de Bayonne, 31060 Toulouse, Cedex 
03, France. 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 Office of the 
Federal Register, 800 North Capitol Street, NW., suite 700, Washington, 
DC.

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: 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 Aerospatiale Model ATR72 
series airplanes was published in the Federal Register on February 5, 
1998 (63 FR 5900). That action proposed to require a one-time high 
frequency eddy current inspection to detect cracking of the lower 
fuselage structure, and repair, if necessary. That action also proposed 
to require modification of certain fastener holes in the lower fuselage 
structure.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. Due consideration has been given to 
the single comment received.
    The commenter supports the proposed rule.

Conclusion

    After careful review of the available data, including the comment 
noted above, the FAA has determined that air safety and the public 
interest require the adoption of the rule as proposed.

Cost Impact

    The FAA estimates that 7 airplanes of U.S. registry will be 
affected by this AD.
    Accomplishment of the actions specified in Aerospatiale Service 
Bulletin ATR72-53-1022 will take approximately 80 work hours per 
airplane, at an average labor rate of $60 per work hour. Required parts 
will be provided by the manufacturer at no cost to the operators. Based 
on these figures, the cost impact on U.S. operators of the actions 
specified in this service bulletin and required by this AD is estimated 
to be $4,800 per airplane.
    Accomplishment of the actions specified in Aerospatiale Service 
Bulletin ATR72-53-1034 will take approximately 65 work hours per 
airplane, at an average labor rate of $60 per work hour. Required parts 
will be provided by the manufacturer at no cost to the operators. Based 
on these figures, the cost impact on U.S. operators of the actions 
specified in this service bulletin and required by this AD is estimated 
to be $3,900 per airplane.
    Accomplishment of the actions specified in Aerospatiale Service 
Bulletin ATR72-53-1053 will take approximately 65 work hours per 
airplane, at an average labor rate of $60 per work hour. Required parts 
will be provided by the manufacturer at no cost to the operators. Based 
on these figures, the cost impact on U.S. operators of the actions 
specified in this service bulletin and required by this AD is estimated 
to be $3,900 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.

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 
Administrator, the Federal Aviation Administration amends part 39 of 
the Federal Aviation Regulations (14 CFR part 39) as follows:

[[Page 20300]]

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:

98-09-04 Aerospatiale: Amendment 39-10483. Docket 97-NM-263-AD.

    Applicability: Model ATR72 series airplanes on which 
Aerospatiale Modification 2879 or Modification 2628 has not been 
incorporated, certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
otherwise 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 reduced structural integrity of the airplane due to 
fatigue cracking in the lower fuselage structure, accomplish the 
following:
    (a) Prior to the accumulation of 17,500 total flight cycles, or 
within 500 flight cycles after the effective date of this AD, 
whichever occurs later: Except as provided in paragraph (b) of this 
AD, perform a one-time high frequency eddy current inspection to 
detect fatigue cracking around the fastener holes in the lower 
fuselage structure in the area of the side brace fitting near frame 
25 on the left-and right-hand sides, and modify crack-free fastener 
holes, as required by paragraph (a)(1) and/or (a)(2) of this AD, as 
applicable.
    (1) For airplanes on which Aerospatiale Modification 2879 has 
not been installed: Perform the inspection and modification in 
accordance with Aerospatiale Service Bulletin ATR72-53-1022, 
Revision 2, dated February 20, 1995.
    (2) For airplanes on which Aerospatiale Modification 2628 has 
not been installed: Perform the inspection and modifications in 
accordance with Aerospatiale Service Bulletins ATR72-53-1034, 
Revision 1, and ATR72-53-1053, Revision 1, both dated March 28, 
1995.
    (b) If any crack or oversize hole is found during the 
accomplishment of paragraph (a) of this AD, and if any service 
bulletin listed in paragraph (a) of this AD specifies to contact the 
manufacturer for an appropriate corrective action: Prior to further 
flight, repair the discrepancy in accordance with a method approved 
by the Manager, International Branch, ANM-116, FAA, Transport 
Airplane Directorate.
    (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. 
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 2: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the International Branch, ANM-116.

    (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.
    (e) The actions shall be done in accordance with the following 
Aerospatiale service bulletins, which contain the following list of 
effective pages:

----------------------------------------------------------------------------------------------------------------
  Service  bulletin  referenced                                        Revision level                           
             and date                  Page number shown on page       shown on page       Date shown on page   
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ATR72-53-1034, Revision 1, March   1, 7, 9, 11-17, 20, 21, 23-25,     1..............  March 28, 1995.          
 28, 1995.                          29, 30.                                                                     
                                   2-6, 8, 10, 18, 19, 22, 26-28....  Original.......  November 4, 1994.        
ATR72-53-1022, Revision 2,         1, 11, 12, 16....................  2..............  February 20, 1995.       
 February 20, 1995.                                                                                             
                                   2................................  1..............  November 10, 1994.       
                                   3-10, 13-15, 17-24...............  Original.......  July 29, 1994.           
ATR72-53-1053, Revision 1, March   1, 6-8, 16, 19...................  1..............  March 28, 1995.          
 28, 1995.                                                                                                      
                                   2-5, 9-15, 17, 18, 20............  Original.......  November 7, 1994.        
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    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 Aerospatiale, 316 Route de 
Bayonne, 31060 Toulouse, Cedex 03, France. 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.

    Note 3: The subject of this AD is addressed in French 
airworthiness directive 94-191-022(B), dated August 17, 1994.

    (f) This amendment becomes effective on May 29, 1998.

    Issued in Renton, Washington, on April 15, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-10478 Filed 4-23-98; 8:45 am]
BILLING CODE 4910-13-P