[Federal Register Volume 68, Number 246 (Tuesday, December 23, 2003)]
[Rules and Regulations]
[Pages 74172-74173]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 03-31270]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 2002-NM-92-AD; Amendment 39-13399; AD 2003-26-03]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A319, A320, and A321 
Series Airplanes Equipped With Certain Litton Air Data Inertial 
Reference Units

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule.

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SUMMARY: This amendment adopts a new airworthiness directive (AD), 
applicable to certain Airbus Model A319, A320, and A321 series 
airplanes equipped with certain Litton air data inertial reference 
units (ADIRU). This AD requires modifying the shelf (floor panel) above 
ADIRU 3, and, for certain airplanes, modifying the polycarbonate guard 
that covers the ADIRUs, and the ladder located in the avionics 
compartment, as applicable. This action is necessary to prevent failure 
of ADIRU 3 during flight, which could result in loss of one source of 
critical attitude and airspeed data and reduce the ability of the 
flightcrew to control the airplane. This action is intended to address 
the identified unsafe condition.

DATES: Effective January 27, 2004.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of January 27, 2004.

ADDRESSES: The service information referenced in this AD may be 
obtained from Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac 
Cedex, 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: Tim Dulin, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2141; 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 Airbus Model A319, A320, 
and A321 series airplanes equipped with certain Litton

[[Page 74173]]

air data inertial reference units (ADIRU) that was published in the 
Federal Register on October 8, 2003 (68 FR 58050). That action proposed 
to require modifying the shelf (floor panel) above ADIRU 3, and, for 
certain airplanes, modifying the polycarbonate guard which covers the 
ADIRUs, and the ladder located in the avionics compartment, as 
applicable.

Comments

    Interested persons have been afforded an opportunity to participate 
in the making of this amendment. No comments were submitted in response 
to the proposal or the FAA's determination of the cost to the public.

Conclusion

    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 200 airplanes of U.S. registry will be 
affected by this AD, that it will take approximately 4 work hours per 
airplane to accomplish the required actions, and that the average labor 
rate is $65 per work hour. Required parts will cost approximately $300 
per airplane. Based on these figures, the cost impact of the AD on U.S. 
operators is estimated to be $112,000, or $560 per airplane.
    The cost impact figure discussed above is 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. The cost impact figures discussed 
in AD rulemaking actions represent only the time necessary to perform 
the specific actions actually required by the AD. These figures 
typically do not include incidental costs, such as the time required to 
gain access and close up, planning time, or time necessitated by other 
administrative actions.

Regulatory Impact

    The regulations adopted herein will 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 final rule does not have federalism 
implications under Executive Order 13132.
    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

0
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

0
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]

0
2. Section 39.13 is amended by adding the following new airworthiness 
directive:

2003-26-03 Airbus: Amendment 39-13399. Docket 2002-NM-92-AD.

    Applicability: Model A319, A320, and A321 series airplanes; 
certificated in any category; equipped with Litton air data inertial 
reference units (ADIRU) installed per Airbus Modification 24852, 
25108, 25336, 26002, or 28218; except those airplanes on which 
Airbus Modification 30650 or 30872 has been accomplished.
    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of ADIRU 3 during flight, which could result 
in loss of one source of critical attitude and airspeed data and 
reduce the ability of the flightcrew to control the airplane, 
accomplish the following:

Modification

    (a) Within 2 years after the effective date of this AD: Do the 
modifications specified in paragraphs (a)(1), (a)(2), and (a)(3) of 
this AD, as applicable, in accordance with paragraphs A. through D. 
of the Accomplishment Instructions of Airbus Service Bulletin A320-
25-1248, dated February 16, 2001; as applicable.
    (1) For all airplanes: Modify the shelf (floor panel) above 
ADIRU 3 by installing shims between the shelf and the webs of the 
shelf support structure.
    (2) For airplanes with Airbus Modification 25900P3941 or Airbus 
Service Bulletin A320-25-1200 accomplished as of the effective date 
of this AD: Modify the polycarbonate guard (umbrella) protecting the 
ADIRUs by installing shims between the guard and the shelf support 
structure.
    (3) For airplanes with Airbus Modification 23027P2852 or Airbus 
Service Bulletin A320-52-1038 accomplished as of the effective date 
of this AD: Modify the ladder located in the avionics compartment by 
machining the slot at the foot of the ladder to increase the depth 
by 0.236 inch.

Alternative Methods of Compliance

    (b) In accordance with 14 CFR 39.19, the Manager, International 
Branch, ANM-116, FAA, Transport Airplane Directorate, is authorized 
to approve alternative methods of compliance for this AD.

Incorporation by Reference

    (c) The actions shall be done in accordance with Airbus Service 
Bulletin A320-25-1248, dated February 16, 2001. 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 Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac 
Cedex, 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 1: The subject of this AD is addressed in French 
airworthiness directive 2002-125(B), dated March 6, 2002.

Effective Date

    (d) This amendment becomes effective on January 27, 2004.

    Issued in Renton, Washington, on December 12, 2003.
Kevin M. Mullin,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 03-31270 Filed 12-22-03; 8:45 am]
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