AD Amdt-39-10772

[Federal Register Volume 63, Number 182 (Monday, September 21, 1998)]
[Rules and Regulations]
[Pages 50132-50134]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 98-24903]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-44-AD; Amendment 39-10772; AD 98-20-06]
RIN 2120-AA64


Airworthiness Directives; Aerospatiale Model ATR42 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 ATR42 series airplanes, that 
requires modification of the electrical power supply for the standby 
horizon indicator. 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 
loss of the standby horizon indicator in the event of failure of 
emergency direct current (DC) power, which could result in reduced 
controllability of the airplane during instrument flight rules 
conditions.

DATES: Effective October 26, 1998.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of October 26, 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 ATR42 
series airplanes was published in the Federal Register on May 12, 1998 
(63 FR 26106). That action proposed to require modification of the 
electrical power supply for the standby horizon indicator.
    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, an operator of the affected airplanes, requests that 
the proposed rule be revised as follows:

--For airplanes on which Aerospatiale Modification 03059 has not been 
accomplished, allow accomplishment of the actions specified in the 
original issue of Avions de Transport Regional Service Bulletin ATR42-
34-0090.
--For all other airplanes, Revision 1 of that service bulletin should 
be required to be accomplished.

    The commenter notes that Revision 1 of the service bulletin is 
specified in the proposed rule as the appropriate source of service 
information for all affected airplanes. The commenter states that, from 
a technical standpoint, there is no difference between the original 
issue and Revision 1 of the service bulletin in regard to installations 
accomplished on

[[Page 50133]]

its fleet. The commenter adds that Revision 1 integrates additional 
wiring options in Figures 9, 19, and 20 of the service bulletin (in 
regard to the commenter's fleet) for airplanes on which Aerospatiale 
Modification 03059 has been accomplished; that modification does not 
apply to the commenter's fleet.
    The FAA does not concur with the commenter's request. The FAA has 
confirmed that some airplanes on which Aerospatiale Modification 03059 
has not been accomplished that have been modified in accordance with 
the original issue of the service bulletin do not require additional 
work in accordance with Revision 1. However, other such airplanes do 
require additional work because of certain changes in the wiring design 
contained in Revision 1.
    An operator of airplanes that have been modified previously in 
accordance with the original issue of the service bulletin should 
review the work specified in Revision 1 to determine what additional 
work is necessary for its affected fleet. If no additional work is 
necessary to conform to Revision 1 of the service bulletin, those 
airplanes would be considered to be in compliance with the AD, as 
provided by the phrase, ``unless accomplished previously'', in the 
compliance provision of the AD. No change to this final rule is 
necessary.

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 as proposed.

Cost Impact

    The FAA estimates that 88 airplanes of U.S. registry will be 
affected by this AD, that it will take approximately 10 to 55 work 
hours per airplane to accomplish the required modification (depending 
on how many kits are needed for each airplane), and that the average 
labor rate is $60 per work hour. Based on these figures, the cost 
impact of the AD on U.S. operators is estimated to be between $52,800 
and $290,400, or between $600 and $3,300 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:

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:

98-20-06  Aerospatiale: Amendment 39-10772. Docket 98-NM-44-AD.

    Applicability: Model ATR42-200, -300, and -320 series airplanes 
on which Aerospatiale Modification 4647 has not been accomplished; 
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 (b) 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 loss of the standby horizon indicator in the event of 
failure of emergency direct current (DC) power, which could result 
in reduced controllability of the airplane during instrument flight 
rules conditions, accomplish the following:
    (a) Within 12 months after the effective date of this AD, modify 
the electrical power supply for the standby horizon indicator in 
accordance with Avions de Transport Regional Service Bulletin ATR42-
34-0090, Revision 1, dated April 22, 1997.
    (b) 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 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.

    (c) 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.
    (d) The actions shall be done in accordance with Avions de 
Transport Regional Service Bulletin ATR42-34-0090, Revision 1, dated 
April 22, 1997, which contains the following list of effective 
pages:

------------------------------------------------------------------------
                                    Revision level                      
            Page No.                shown on page     Date shown on page
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1-4, 15, 29-37, 49-52, 55-62,    1..................  April 22, 1997.   
 69-72.                                                                 
5-14, 16-28, 38-48, 52, 53, 63-  Original...........  December 6, 1997. 
 68, 73, 74.                                                            
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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 96-230-066(B), dated October 23, 1996.

    (e) This amendment becomes effective on October 26, 1998.


[[Page 50134]]


    Issued in Renton, Washington, on September 11, 1998.
Dorenda D. Baker,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-24903 Filed 9-18-98; 8:45 am]
BILLING CODE 4910-13-U