[Federal Register Volume 70, Number 106 (Friday, June 3, 2005)]
[Proposed Rules]
[Pages 32547-32550]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 05-11062]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2005-21343; Directorate Identifier 2004-NM-117-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and 
F4-600R Series Airplanes, and Model C4-605R Variant F Airplanes 
(Collectively Called A300-600 Series Airplanes); and Model A310 Series 
Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for certain Airbus models, as specified above. This proposed AD would 
require modifying the aft pressure bulkhead for improved corrosion 
protection and drainage, and related concurrent actions. This proposed 
AD is prompted by severe corrosion found in the lower rim area of the 
aft pressure bulkhead during routine maintenance of an airplane. We are 
proposing this AD to prevent corrosion on the inner rim angle and cleat 
profile splice of the aft

[[Page 32548]]

pressure bulkhead, which could result in the loss of airplane 
structural integrity.

DATES: We must receive comments on this proposed AD by July 5, 2005.

ADDRESSES: Use one of the following addresses to submit comments on 
this proposed AD.
     DOT Docket Web Site: Go to http://dms.dot.gov and follow 
the instructions for sending your comments electronically.
     Government-wide Rulemaking Web Site: Go to http://www.regulations.gov and follow the instructions for sending your 
comments electronically.
     Mail: Docket Management Facility, U.S. Department of 
Transportation, 400 Seventh Street SW., Nassif Building, room PL-401, 
Washington, DC 20590.
     By Fax: (202) 493-2251.
     Hand Delivery: Room PL-401 on the plaza level of the 
Nassif Building, 400 Seventh Street SW., Washington, DC, between 9 a.m. 
and 5 p.m., Monday through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France.
    You can examine the contents of this AD docket on the Internet at 
http://dms.dot.gov, or in person at the Docket Management Facility, 
U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, 
on the plaza level of the Nassif Building, Washington, DC. This docket 
number is FAA-2005-21343; the directorate identifier for this docket is 
2004-NM-117-AD.

FOR FURTHER INFORMATION CONTACT: Tim Backman, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 
227-2797; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to submit any relevant written data, views, or 
arguments regarding this proposed AD. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2005-21343; 
Directorate Identifier 2004-NM-117-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of the proposed AD. We will 
consider all comments submitted by the closing date and may amend the 
proposed AD in light of those comments.
    We will post all comments we receive, without change, to http://dms.dot.gov, including any personal information you provide. We will 
also post a report summarizing each substantive verbal contact with FAA 
personnel concerning this proposed AD. Using the search function of our 
docket Web site, anyone can find and read the comments in any of our 
dockets, including the name of the individual who sent the comment (or 
signed the comment on behalf of an association, business, labor union, 
etc.). You can review the DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
can visit http://dms.dot.gov.

Examining the Docket

    You can examine the AD docket on the Internet at http://dms.dot.gov, or in person at the Docket Management Facility office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Management Facility office (telephone (800) 647-
5227) is located on the plaza level of the Nassif Building at the DOT 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after the DMS receives them.

Discussion

    The Direction G[eacute]n[eacute]rale de l'Aviation Civile (DGAC), 
which is the airworthiness authority for France, notified us that an 
unsafe condition may exist on certain Airbus Model A300 B4-600, B4-
600R, and F4-600R series airplanes, and Model C4-605R Variant F 
airplanes (collectively called A300-600 series airplanes); and Model 
A310 series airplanes. The DGAC advises that severe corrosion has been 
found in the lower rim area of the aft pressure bulkhead during routine 
maintenance of an airplane that has been in service for 10 years. On 
several other airplanes, less severe corrosion also has been found on 
the inner rim angle of the bulkhead in the area of the drain hole and 
on the cleat profile splice at the airplane centerline. Damage to the 
surface protection during cleaning of the drain hole or during 
incorporation of certain Airbus service bulletins could lead to 
corrosion on the inner rim angle of the bulkhead. Also, clogged drain 
holes or incomplete adhesion of the sealant during incorporation of 
certain Airbus service bulletins could lead to corrosion on the cleat 
profile splice. Corrosion on the inner rim angle and cleat profile 
splice of the aft pressure bulkhead, if not corrected, could result in 
the loss of airplane structural integrity.

Other Related Rulemaking

    On March 3, 1988, we issued AD 88-06-03, amendment 39-5871 (53 FR 
7730, March 10, 1988), applicable to certain Airbus Model A310 series 
airplanes. That AD requires repetitive X-ray or eddy current 
inspections of the rear pressure bulkhead for cracks and repair if 
cracks are found; and modification of the attachment of the rear 
pressure bulkhead to FR 80/82. If paragraph A.2. of AD 88-06-03 has 
been accomplished in accordance with Airbus Service Bulletin A310-53-
2025, original issue, dated April 21, 1986, or Revision 3, dated April 
7, 1987, operators do not need to do the related concurrent actions for 
Model A310 series airplanes that would be required by this proposed AD.

Relevant Service Information

    Airbus has issued service bulletins A300-53-6017 (for Model A300-
600 series airplanes) and A310-53-2036 (for Model A310 series 
airplanes), both Revision 02, both dated February 25, 2004. The service 
bulletins describe procedures for modifying the aft pressure bulkhead 
for improved corrosion protection and drainage, and related concurrent 
actions. The modification includes the following actions:
    1. Removing the existing corrosion protection at the aft pressure 
bulkhead, which includes raising or renewing sealant beads between the 
cleat profile, rim angle, and circumferential strap up to STGR27; and 
applying a corrosion inhibitor in the whole area of the aft pressure 
bulkhead up to STGR27.
    2. Enlarging the drain hole in the cleat profile, which includes 
reworking the attachment angles; and removing the sealant between the 
cleat profile, rim angle, and circumferential strap up to STGR27 if the 
sealant beads are damaged.
    3. Applying sealant and corrosion inhibitor at FR80 up to STGR27.
    4. Replacing the heat and sound insulation between FR79 and FR80.
    Accomplishing the actions specified in the service information is 
intended to adequately address the unsafe condition. The DGAC mandated 
the service information and issued French airworthiness directive F-
2004-004, dated January 7, 2004, to ensure the continued airworthiness 
of these airplanes in France.
    Airbus Service Bulletin A300-53-6017 specifies prior or concurrent 
accomplishment of Airbus Service Bulletin A300-53-6006, Revision 3, 
dated March 24, 1989 (for Model A300-600 series airplanes).

[[Page 32549]]

    Airbus Service Bulletin A310-53-2036 specifies prior or concurrent 
accomplishment of Airbus Service Bulletin A310-53-2025, Revision 5, 
dated March 24, 1989 (for Model A310 series airplanes).

Concurrent Service Bulletins

    Airbus Service Bulletins A300-53-6006 and A310-53-2025 describe 
procedures for modifying the aft pressure bulkhead to improve the 
fatigue life of the attachment angles at FR80/82. The modification 
includes the following:
     For certain airplanes, doing a visual inspection around 
the entire circumference between FR80/82 and the aft pressure bulkhead 
for damaged filler; and if filler material is lacking or damaged, 
removing the damaged filler and adjacent area around damage.
     On airplanes that have accumulated between 6,000 and 
12,000 total flight cycles, inspecting the critical area from STGR7 to 
STGR17, left and right; and if cracks are found, repairing the aft 
pressure bulkhead between STGR9 and STGR13.
     Removing the sealant on the whole circumference from 
between FR80/82 and the aft pressure bulkhead.
     Installing additional attachment angles on the 
circumference of FR80/82.
     Filling the space between the aft pressure bulkhead and 
FR80/82 beginning at STGR57 with a certain filler.
     Installing additional supports between the aft pressure 
bulkhead and FR80/82 in the area of STGR9.
     Installing an additional frame stiffener and support 
between the aft pressure bulkhead and FR79 at STGR13.
     Modifying the aft lavatories by installing a new, upper 
sidewall panel and affixing strips of tape on certain areas of the new, 
upper sidewall panel.
     Applying surface protection to the modified area of the 
aft pressure bulkhead.
     Modifying, reidentifying, and installing the heat and 
sound insulation in the area of STGR9 and STGR 13, left and right, and 
between FR79 and FR80/82, left and right.

FAA's Determination and Requirements of the Proposed AD

    These airplane models are manufactured in France and are 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. We have examined the DGAC's findings, 
evaluated all pertinent information, and determined that we need to 
issue an AD for products of this type design that are certificated for 
operation in the United States.
    Therefore, we are proposing this AD, which would require 
accomplishing the actions specified in the service information 
described previously.

Clarification of Inspection Terminology

    The ``visual inspection'' specified in the concurrent service 
bulletins is referred to as a ``general visual inspection'' in this 
proposed AD. We have included the definition for a general visual 
inspection in a note in the proposed AD.

Costs of Compliance

    The following table provides the estimated costs (at an average 
labor rate of $65 per hour) for U.S. operators to comply with this 
proposed AD.

                                                                     Estimated Costs
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                                                                                                                      Number of U.S.
             Models                      Action             Work hours             Parts          Cost per airplane     registered        Fleet cost
                                                                                                                         airplanes
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A300-600 series airplanes.......  Modification.......  34.................  $1,200.............  $3,410.............               0  $0.
                                  Concurrent           Between 590 and 660  Between $2,442 and   Between $40,792 and               0  $0.
                                   Action\1\.                                $9,884.              $52,784.
A310 series airplanes...........  Modification.......  34.................  $1,200.............  $3,410.............              52  $177,320.
                                  Concurrent           Between 590 and 660  Between $2,442 and   Between $40,792 and              52  Between $2,121,184
                                   Action\1\.                                $9,884.              $52,784.                             and $2,744,768.
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\1\ The number of work hours and estimated costs for concurrent actions depend on airplane configuration.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
subtitle VII, part A, subpart III, section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

Regulatory Findings

    We have determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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.
    For the reasons discussed above, I certify that the 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. 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.
    We prepared a regulatory evaluation of the estimated costs to 
comply with this proposed AD. See the ADDRESSES section for a location 
to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

[[Page 32550]]

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 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. The FAA amends Sec.  39.13 by adding the following new 
airworthiness directive (AD):

Airbus: Docket No. FAA-2005-21343; Directorate Identifier 2004-NM-
117-AD.

Comments Due Date

    (a) The Federal Aviation Administration must receive comments on 
this AD action by July 5, 2005.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Airbus Model A300 B4-600, B4-600R, and 
F4-600R series airplanes, and Model C4-605R Variant F airplanes 
(collectively called A300-600 series airplanes); and Model A310 
series airplanes; certificated in any category; except those 
modified in production by Airbus Modification 6788.

Unsafe Condition

    (d) This AD was prompted by severe corrosion found in the lower 
rim area of the aft pressure bulkhead during routine maintenance of 
an airplane. We are issuing this AD to prevent corrosion on the 
inner rim angle and cleat profile splice of the aft pressure 
bulkhead, which could result in the loss of airplane structural 
integrity.

Compliance

    (e) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Service Bulletin References

    (f) The term ``service bulletin,'' as used in this AD, means the 
Accomplishment Instructions of the following service bulletins 
listed in Table 1 of this AD, as applicable:

                                      Table 1.--Service Bulletin References
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                 Models                           Requirement                   Airbus service bulletin
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A300-600 series airplanes...............  Paragraph (g) of this AD...  A300-53-6017, Revision 02, dated February
                                                                        25, 2004.
                                          Paragraph (h) of this AD...  A300-53-6006, Revision 3, dated March 24,
                                                                        1989.
A310 series airplanes...................  Paragraph (g) of this AD...  A310-53-2036, Revision 02, dated February
                                                                        25, 2004.
                                          Paragraph (h) of this AD...  A310-53-2025, Revision 5, dated March 24,
                                                                        1989.
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Modification To Improve Corrosion Protection and Drainage

    (g) Within 60 months after the effective date of this AD, modify 
the aft pressure bulkhead for improved corrosion protection and 
drainage by doing all of the actions specified in the Accomplishment 
Instructions of the applicable service bulletin.

Concurrent Modification To Improve Attachment Angles

    (h) Before or concurrently with accomplishing the modification 
required by paragraph (g) of this AD, modify the aft pressure 
bulkhead to improve the fatigue life of the attachment angles at 
FR80/82 by doing all of the actions specified in the Accomplishment 
Instructions of the applicable service bulletin. Where the service 
bulletin specifies doing a visual inspection around the entire 
circumference between FR80/82 and the aft pressure bulkhead for 
damaged filler, do a general visual inspection.

    Note 1: For the purposes of this AD, a general visual inspection 
is: ``A visual examination of an interior or exterior area, 
installation, or assembly to detect obvious damage, failure, or 
irregularity. This level of inspection is made from within touching 
distance unless otherwise specified. A mirror may be necessary to 
ensure visual access to all surfaces in the inspection area. This 
level of inspection is made under normally available lighting 
conditions such as daylight, hangar lighting, flashlight, or 
droplight and may require removal or opening of access panels or 
doors. Stands, ladders, or platforms may be required to gain 
proximity to the area being checked.''

Credit for Concurrent Actions

    (i) For Model A310 series airplanes, accomplishment of the 
actions specified in paragraph A.2. of AD 88-06-03, amendment 39-
5871 (53 FR 7730, March 10, 1988), is considered acceptable for 
compliance with the requirements of paragraph (h) of this AD.

Credit for Previous Service Bulletins

    (j) Actions done before the effective date of this AD in 
accordance with Airbus Service Bulletin A310-53-2036, Revision 01, 
dated October 9, 2003 (for Model A310 series airplanes), are 
acceptable for compliance with the requirements of paragraph (g) of 
this AD.

Alternative Methods of Compliance (AMOCs)

    (k) The Manager, International Branch, ANM-116, Transport 
Airplane Directorate, FAA, has the authority to approve AMOCs for 
this AD, if requested in accordance with the procedures found in 14 
CFR 39.19.

Related Information

    (l) French airworthiness directive F-2004-004, dated January 7, 
2004, also addresses the subject of this AD.

    Issued in Renton, Washington, on May 26, 2005.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 05-11062 Filed 6-2-05; 8:45 am]
BILLING CODE 4910-13-P