[Federal Register Volume 63, Number 71 (Tuesday, April 14, 1998)]
[Proposed Rules]
[Pages 18153-18155]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-9751]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-20-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A320-111, -211, and -231 
Series Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

-----------------------------------------------------------------------

SUMMARY: This document proposes the adoption of a new airworthiness 
directive (AD) that is applicable to certain Airbus Model A320-111, -
211, and -231 series airplanes. This proposal would require repetitive 
inspections to detect missing or cracked bolts and fittings of the 
frame-to-pressure-floor connection; and corrective actions, if 
necessary. This proposal also provides for optional terminating action 
for the repetitive inspections of the affected fittings. 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 detect and correct fatigue 
cracking in the bolts and fittings of the frame-to-pressure-floor 
connection, which could result in reduced structural integrity of the 
airplane.

DATES: Comments must be received by May 14, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-20-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 Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 
Blagnac Cedex, France. 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:

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 98-NM-20-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. 98-NM-20-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    The Direction Generale de l'Aviation Civile (DGAC), which is the 
airworthiness authority for France, notified the FAA that an unsafe 
condition may exist on certain Airbus Model A320-111, -211, and -231 
series airplanes. The DGAC advises that, during a structural fatigue 
test, the inboard aft bolt at the right side of frame 43 sheared off 
after 76,055 simulated flights. In addition, a crack developed in the 
frame fitting at the right side of frame 43 after 81,551 simulated 
flights. Such fatigue cracking, if not detected and corrected in a 
timely manner, could result in reduced structural integrity of the 
airplane.

Explanation of Relevant Service Information

    Airbus has issued Service Bulletin A320-53-1083, Revision 2, dated 
August 28, 1997, which describes procedures for repetitive detailed 
visual inspections to detect cracking of the bolts and fittings of the 
frame-to-pressure-floor connection at frames (FR) 43 and 44 and to 
determine if any bolt is missing. The service bulletin also describes 
procedures for replacement of cracked or missing bolts and fittings 
with new or serviceable parts.
    The service bulletin references Airbus Service Bulletin A320-53-
1015, Revision 02, dated July 17, 1997, as an additional source of 
service information for accomplishment of the replacement. Airbus 
Service Bulletin A320-53-1015 also describes procedures for 
reinforcement of the frame segments and frame fittings at FR 43 and FR 
44 between left and right stringers 18 and 23. Such reinforcement, if 
accomplished, eliminates the need for the repetitive inspections for 
the affected fitting.
    The DGAC classified Airbus Service Bulletin A320-53-1083 as 
mandatory and issued French airworthiness directive 97-316-110(B), 
dated October 22, 1997, in order to assure the continued airworthiness 
of these airplanes in France.

FAA's Conclusions

    This airplane model is manufactured in France and is 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 DGAC has kept the FAA informed 
of the situation described above. The FAA has examined the findings of 
the DGAC, 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 Airbus Service Bulletins A320-53-

[[Page 18154]]

1083 and A320-53-1015 (for certain corrective actions), described 
previously, except as discussed in the ``Differences Between Proposed 
Rule and Service Bulletins'' paragraph below. The proposed AD also 
would provide for optional terminating action for the repetitive 
inspections of the affected fittings.
    Operators should note that, in consonance with the findings of the 
DGAC, the FAA has determined that the repetitive inspections proposed 
by this AD can be allowed to continue in lieu of accomplishment of a 
terminating action. In making this determination, the FAA considers 
that, in this case, long-term continued operational safety will be 
adequately assured by accomplishing the repetitive inspections to 
detect cracking before it represents a hazard to the airplane.

Differences Between Proposed Rule and Service Bulletins

    Operators also should note that, unlike the procedures described in 
Airbus Service Bulletins A320-53-1083 and A320-53-1015, this proposed 
AD would not permit further flight if cracks are detected in the bolts 
and fittings of the frame-to-pressure-floor connection at frames 43 and 
44. The FAA has determined that, because of the safety implications and 
consequences associated with such cracking, corrective actions for any 
fitting or bolt of the frame-to-pressure-floor connection at frames 43 
and 44 that is found to be cracked must be accomplished prior to 
further flight.

Cost Impact

    The FAA estimates that 5 airplanes of U.S. registry would be 
affected by this proposed AD, that it would take approximately 9 work 
hours per airplane to accomplish the proposed inspection, and that the 
average labor rate is $60 per work hour. Based on these figures, the 
cost impact of the inspection proposed by this AD on U.S. operators is 
estimated to be $2,700, or $540 per airplane, per inspection cycle.
    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.
    Should an operator elect to accomplish the optional terminating 
action that would be provided by this AD action, it would take 
approximately 119 work hours to accomplish it, at an average labor rate 
of $60 per work hour. The cost of required parts would be approximately 
$12,920 per airplane. Based on these figures, the cost impact of the 
optional terminating action would be $20,060 per airplane.

Regulatory Impact

    The regulations proposed herein would 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 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    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:

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:

Airbus Industrie: Docket 98-NM-20-AD.
    Applicability: Model A320-111, -211, and -231 series airplanes; 
as listed in Airbus Service Bulletin A320-53-1083, Revision 2, dated 
August 28, 1997; 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 detect and correct fatigue cracking in the bolts and fittings 
of the frame-to-pressure-floor connection, which could result in 
reduced structural integrity of the airplane, accomplish the 
following:
    (a) Prior to the accumulation of 20,000 total flight cycles, or 
within 60 days after the effective date of this AD, whichever occurs 
later, perform a detailed visual inspection to detect cracked or 
missing bolts and fittings of the frame-to-pressure-floor connection 
at frames 43 and 44, in accordance with Airbus Service Bulletin 
A320-53-1083, Revision 2, dated August 28, 1997. If no crack is 
detected, repeat the detailed visual inspection thereafter at 
intervals not to exceed 5,100 flight cycles.
    (1) If any bolt is found to be cracked or missing during any 
inspection required by paragraph (a) of this AD, prior to further 
flight, replace the bolt with a new bolt in accordance with the 
service bulletin. Repeat the detailed visual inspection thereafter 
at intervals not to exceed 5,100 flight cycles.
    (2) If any fitting is found to be cracked during any inspection 
required by paragraph (a) of this AD, prior to further flight, 
accomplish the actions specified in paragraph (b) of this AD for the 
cracked fitting and its corresponding bolts and fuselage frame, in 
accordance with Airbus Service Bulletin A320-53-1015, Revision 02, 
dated July 17, 1997.
    (b) Reinforcement of the fitting in accordance with Airbus 
Service Bulletin A320-53-1015, Revision 02, dated July 17, 1997, 
constitutes terminating action for the requirements of this AD for 
the affected fitting.
    (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 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.


[[Page 18155]]


    Note 3: The subject of this AD is addressed in French 
airworthiness directive 97-316-110(B), dated October 22, 1997.

    Issued in Renton, Washington on April 7, 1998.
Darrell M. Pederson,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-9751 Filed 4-13-98; 8:45 am]
BILLING CODE 4910-13-U