[Federal Register Volume 61, Number 77 (Friday, April 19, 1996)]
[Proposed Rules]
[Pages 17257-17259]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-9692]
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. 95-NM-249-AD]
Airworthiness Directives; Airbus Model A320-111, -211, and -231
Series Airplanes
AGENCY: Federal Aviation Administration, DOT.
ACTION: Notice of proposed rulemaking (NPRM).
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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 visual
inspections to detect cracks of the fittings of the pressurized floor
at frame 36, and renewal of the zone protective finish or replacement
of fittings with new fittings, if necessary. This proposal is prompted
by a report of fatigue cracking found on the pressurized floor fitting
at frame 36 under the lower surface panel. The actions specified by the
proposed AD are intended to prevent such fatigue cracking, which could
result in failure of a floor fitting and subsequent depressurization of
the fuselage.
DATES: Comments must be received by May 31, 1996.
ADDRESSES: Submit comments in triplicate to the Federal Aviation
Administration (FAA), Transport Airplane Directorate, ANM-103,
Attention: Rules Docket No. 95-NM-249-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
[[Page 17258]]
Directorate, 1601 Lind Avenue, SW., Renton, Washington.
FOR FURTHER INFORMATION CONTACT: Tim Backman, Aerospace Engineer,
Standardization Branch, ANM-113, FAA, Transport Airplane Directorate,
1601 Lind Avenue SW., Renton, Washington 98055-4056; telephone (206)
227-2797; fax (206) 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 95-NM-249-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-103, Attention: Rules
Docket No. 95-NM-249-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, recently 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 full-scale
fatigue test on a center fuselage test article, cracking occurred on
the pressurized floor fitting at frame 36 under the lower surface pane
after the accumulation of 102,560 simulated flights. The cracking has
been attributed to fatigue. Such fatigue cracking, if not detected and
corrected in a timely manner, could result in failure of a fitting and
subsequent depressurization of the fuselage.
Airbus has issued Service Bulletin A320-57-1028, dated August 12,
1991, which describes procedures for visual inspections to detect
cracks of the six fittings of the pressurized floor at frame 36 under
the lower surface panel, and renewal of the zone protective finish, if
necessary. For cases where the length of the cracking is outside
certain limits, the service bulletin describes procedures for
replacement of all cracked fittings with new fittings. However, the
service bulletin permits further flight, under certain conditions, with
a fitting(s) that is cracked and the length of the cracking within
certain limits. The DGAC classified this service bulletin as mandatory
and issued French airworthiness directive 95-099-067(B), dated May 24,
1995, in order to assure the continued airworthiness of these airplanes
in France.
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.
Since an unsafe condition has been identified that is likely to
exist or develop on other airplanes of the same type design, the
proposed AD would require visual inspection(s) to detect cracks of the
six fittings of the pressurized floor at frame 36 under the lower
surface panel, and renewing the zone protective finish or replacement
of the fittings with new fittings, if necessary. The actions would be
required to be accomplished in accordance with the service bulletin
described previously.
Operators should note that, unlike the procedures described in the
referenced service bulletin, this proposed AD would not permit further
flight with cracking detected in any fitting. The FAA has determined
that, due to safety implications and consequences associated with such
cracking, the subject fittings that are found to be cracked must be
replaced. Therefore, for cases where one fitting is cracked and the
length of the cracking is outside certain limits, or where two or more
fittings are cracked, the proposed AD would require replacement of all
six fittings with new fittings. For cases where one fitting is cracked
and the length of the cracking is within certain limits, the proposed
AD would require replacement of that fitting prior to further flight,
and eventual replacement of the remaining five fittings. The
replacement procedures are provided in the service bulletin described
previously.
The FAA estimates that 22 Airbus Model A320-111, -211, and -231
series airplanes of U.S. registry would be affected by this proposed
AD, that it would take approximately 3 work hours per airplane to
accomplish the proposed actions, and that the average labor rate is $60
per work hour. Based on these figures, the cost impact of the proposed
AD on U.S. operators is estimated to be $3,960, or $180 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.
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.
[[Page 17259]]
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 95-NM-249-AD.
Applicability: Model A320-111, -211, and -231 series airplanes;
manufacturer's serial numbers 002 through 008 inclusive, 010 through
014 inclusive, 016 through 078 inclusive, and 080 through 104
inclusive; on which Airbus Modification 21282P01497 (reference
Airbus Service Bulletin A320-57-1029) has not been installed;
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 fatigue cracking on the pressurized floor fitting at
frame 36 under the lower surface panel, which could result in
failure of a fitting and subsequent depressurization of the
fuselage, accomplish the following:
(a) Prior to the accumulation of 16,000 total landings, or
within 6 months after the effective date of this AD, whichever
occurs later, perform a visual inspection to detect cracks of the 6
fittings of the pressurized floor at frame 36 under the lower
surface panel, in accordance with Airbus Service Bulletin A320-57-
1028, dated August 12, 1991.
(1) If no cracking is found, prior to further flight, renew the
zone protective finish in accordance with the service bulletin.
Repeat the visual inspection thereafter at intervals not to exceed
12,000 landings.
(2) If only 1 of the 6 fittings is found to be cracked and that
crack is less than or equal to 0.59 inch (15 mm) in length, prior to
further flight, replace the cracked fitting with a new fitting in
accordance with the service bulletin. Thereafter, prior to the
accumulation of 500 landings following accomplishment of this
replacement, replace the remaining 5 fittings with new fittings in
accordance with the service bulletin.
(3) If only 1 of the 6 fittings is found to be cracked and that
crack is greater than 0.59 inch (15 mm) in length, prior to further
flight, replace all six fittings with new fittings in accordance
with the service bulletin.
(4) If 2 or more fittings are found to be cracked, prior to
further flight, replace all 6 fittings with new fittings in
accordance with the service bulletin.
(b) Replacement of all 6 fittings with new fittings in
accordance with Airbus Service Bulletin A320-57-1028, dated August
12, 1991, constitutes terminating action for the inspection
requirements of this AD.
(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 2: 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
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.
Issued in Renton, Washington, on April 15, 1996.
S.R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification
Service.
[FR Doc. 96-9692 Filed 4-18-96; 8:45 am]
BILLING CODE 4910-13-U
