[Federal Register Volume 72, Number 76 (Friday, April 20, 2007)]
[Proposed Rules]
[Pages 19826-19828]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: E7-7518]


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

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2007-27925; Directorate Identifier 2006-NM-183-AD]
RIN 2120-AA64


Airworthiness Directives; Airbus Model A310 Series Airplanes

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

ACTION: Notice of proposed rulemaking (NPRM).

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

SUMMARY: The FAA proposes to adopt a new airworthiness directive (AD) 
for all Airbus Model A310 series airplanes. This proposed AD would 
require revising the Airworthiness Limitations Section of the 
Instructions for Continued Airworthiness to incorporate new limitations 
for fuel tank systems. This proposed AD results from fuel system 
reviews conducted by the manufacturer. We are proposing this AD to 
prevent the potential of ignition sources inside fuel tanks, which, in 
combination with flammable fuel vapors caused by latent failures, 
alterations, repairs, or maintenance actions, could result in fuel tank 
explosions and consequent loss of the airplane.

DATES: We must receive comments on this proposed AD by May 21, 2007.

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.
     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.
    Contact Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, 
France, for service information identified in this proposed AD.

FOR FURTHER INFORMATION CONTACT: Tom Stafford, Aerospace Engineer, 
International Branch, ANM-116, FAA, Transport Airplane Directorate, 
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 
227-1622; 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 in the ADDRESSES section. Include the docket number ``FAA-2007-
27925; Directorate Identifier 2006-NM-183-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 received 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 
that 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 may review the DOT's complete Privacy Act Statement in the 
Federal Register published on April 11, 2000 (65 FR 19477-78), or you 
may visit http://dms.dot.gov.

Examining the Docket

    You may 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 Docket Management System 
receives them.

Discussion

    The FAA has examined the underlying safety issues involved in fuel 
tank explosions on several large transport airplanes, including the 
adequacy of existing regulations, the service history of airplanes 
subject to those regulations, and existing maintenance practices for 
fuel tank systems. As a result of those findings, we issued a 
regulation titled ``Transport Airplane Fuel Tank System Design Review, 
Flammability Reduction and Maintenance and Inspection Requirements'' 
(66 FR 23086, May 7, 2001). In addition to new airworthiness standards 
for transport airplanes and new maintenance requirements, this rule 
included Special Federal Aviation Regulation No. 88 (``SFAR 88,'' 
Amendment 21-78, and subsequent Amendments 21-82 and 21-83).
    Among other actions, SFAR 88 requires certain type design (i.e., 
type certificate (TC) and supplemental type certificate (STC)) holders 
to substantiate that their fuel tank systems can prevent ignition 
sources in the fuel tanks. This requirement applies to type design 
holders for large turbine-powered transport airplanes and for 
subsequent modifications to those airplanes. It requires them to 
perform design reviews and to develop design changes and maintenance 
procedures if their designs do not meet the new fuel tank safety 
standards. As explained in the preamble to the rule, we intended to 
adopt airworthiness directives to mandate any changes found necessary 
to address unsafe conditions identified as a result of these reviews.
    In evaluating these design reviews, we have established four 
criteria intended to define the unsafe conditions associated with fuel 
tank systems that require corrective actions. The percentage of 
operating time during which fuel tanks are exposed to flammable 
conditions is one of these criteria. The other three criteria address 
the failure types under evaluation: single failures, single failures in 
combination with a latent condition(s), and in-service failure 
experience. For all four criteria, the evaluations included 
consideration of previous actions taken that may mitigate the need for 
further action.
    The Joint Aviation Authorities (JAA) has issued a regulation that 
is similar to SFAR 88. (The JAA is an associated body of the European 
Civil Aviation

[[Page 19827]]

Conference (ECAC) representing the civil aviation regulatory 
authorities of a number of European States who have agreed to co-
operate in developing and implementing common safety regulatory 
standards and procedures.) Under this regulation, the JAA stated that 
all members of the ECAC that hold type certificates for transport 
category airplanes are required to conduct a design review against 
explosion risks.
    We have determined that the actions identified in this proposed AD 
are necessary to reduce the potential of ignition sources inside fuel 
tanks, which, in combination with flammable fuel vapors, could result 
in fuel tank explosions and consequent loss of the airplane.
    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Community, notified us that 
an unsafe condition may exist on all Airbus Model A310 series 
airplanes. The EASA advises that Airbus has issued new fuel 
airworthiness limitations (FALs) to address failure conditions for 
which an unacceptable probability of ignition risk could exist if 
specific tasks or practices or both are not performed in accordance 
with the manufacturer's requirements. The new FALs are intended to 
satisfy the JAA's Interim Policy of Fuel Tank Safety and SFAR 88 
requirements.

Relevant Service Information

    Airbus has issued A310 ALS--Airworthiness Limitations Section, 
dated May 31, 2006, which is a repository for stand-alone documents 
that are approved independently from each other. The Airbus A310 ALS 
comprises the following documents:
     ALS Part 1--Safe Life Airworthiness Limitation Items
     ALS Part 2--Damage-Tolerant Airworthiness Limitation Items
     ALS Part 3--Certification Maintenance Requirements
     ALS Part 4--Aging Systems Maintenance
     ALS Part 5--Fuel Airworthiness Limitations
    Airbus ALS Part 5--Fuel Airworthiness Limitations, dated May 31, 
2006, refers to Airbus A310 Fuel Airworthiness Limitations, Document 
95A.1930/05, Issue 1, dated December 19, 2005 (approved by the EASA on 
March 13, 2006). Section 1, ``Maintenance/Inspection Tasks,'' of 
Document 95A.1930/05 describes certain FAL inspections, which are 
periodic inspections of certain features for latent failures that could 
contribute to an ignition source. Section 2, ``Critical Design 
Configuration Control Limitations,'' of Document 95A.1930/05 identifies 
critical design configuration control limitations (CDCCLs). A CDCCL is 
a limitation requirement to preserve a critical ignition source 
prevention feature of the fuel tank system design that is necessary to 
prevent the occurrence of an unsafe condition. The purpose of a CDCCL 
is to provide instruction to retain the critical ignition source 
prevention feature during configuration change that may be caused by 
alterations, repairs, or maintenance actions. A CDCCL is not a periodic 
inspection.
    Accomplishing the actions specified in the service information is 
intended to adequately address the unsafe condition. The EASA mandated 
the service information and issued airworthiness directive 2006-0202, 
dated July 11, 2006, to ensure the continued airworthiness of these 
airplanes in the European Union.

FAA's Determination and Requirements of the Proposed AD

    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. As described in FAA 
Order 8100.14A, ``Interim Procedures for Working With the European 
Community on Airworthiness Certification and Continued Airworthiness,'' 
dated August 12, 2005, the EASA has kept the FAA informed of the 
situation described above. We have examined the EASA's findings, 
evaluated all pertinent information, and determined that we need to 
issue an AD for airplanes of this type design that are certificated for 
operation in the United States.
    Therefore, we are proposing this AD, which would require revising 
the Airworthiness Limitations Section of the Instructions for Continued 
Airworthiness to incorporate new limitations for fuel tank systems.

Differences Between the Proposed AD and EASA Airworthiness Directive

    For airplanes that have exceeded 34,000 total flight hours as of 
effective date of the EASA airworthiness directive 2006-0202, the EASA 
airworthiness directive states that Task 28-18-00-03-1, ``Operational 
check of lo-level/underfull/calibration sensors,'' must be done within 
6 years or 20,000 flight hours after the effective date. This AD, 
however, would require accomplishing Task 28-18-00-03-1 at the later of 
the following compliance times: (1) Prior to the accumulation of 40,000 
total flight hours, or (2) within 72 months or 20,000 flight hours 
after the effective date of this AD, whichever occurs first. The EASA 
is considering further rulemaking to implement this change in the 
compliance time.
    EASA airworthiness directive 2006-0202 states that the defined 
intervals for the FALs have to be counted from the effective date of 
the EASA airworthiness directive. This proposed AD would instead start 
counting the first interval of the FALs from the later of the following 
compliance times: (1) The effective date of this AD, or (2) the date of 
issuance of the original French standard airworthiness certificate or 
the date of issuance of the original French export certificate of 
airworthiness. The EASA also is considering further rulemaking to 
implement this change in the compliance time.

Costs of Compliance

    This proposed AD would affect about 69 airplanes of U.S. registry. 
The proposed actions would take about 2 work hours per airplane, at an 
average labor rate of $80 per work hour. Based on these figures, the 
estimated cost of the proposed AD for U.S. operators is $11,040, or 
$160 per airplane.

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.

[[Page 19828]]

    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 and placed it in the AD docket. 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.

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 Federal Aviation Administration (FAA) amends Sec.  39.13 by 
adding the following new airworthiness directive (AD):

Airbus: Docket No. FAA-2007-27925; Directorate Identifier 2006-NM-
183-AD.

Comments Due Date

    (a) The FAA must receive comments on this AD action by May 21, 
2007.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to all Airbus Model A310 series airplanes, 
certificated in any category.

    Note 1: This AD requires revisions to certain operator 
maintenance documents to include new inspections and critical design 
configuration control limitations (CDCCLs). Compliance with the 
operator maintenance documents is required by 14 CFR 91.403(c). For 
airplanes that have been previously modified, altered, or repaired 
in the areas addressed by these inspections and CDCCLs, the operator 
may not be able to accomplish the inspections and CDCCLs described 
in the revisions. In this situation, to comply with 14 CFR 
91.403(c), the operator must request approval for an alternative 
method of compliance according to paragraph (j) of this AD. The 
request should include a description of changes to the required 
inspections and CDCCLs that will preserve the critical ignition 
source prevention feature of the affected fuel system.

Unsafe Condition

    (d) This AD results from fuel system reviews conducted by the 
manufacturer. We are issuing this AD to prevent the potential of 
ignition sources inside fuel tanks, which, in combination with 
flammable fuel vapors caused by latent failures, alterations, 
repairs, or maintenance actions, could result in fuel tank 
explosions and consequent loss of the airplane.

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.

Revise Airworthiness Limitations Section (ALS) to Incorporate Fuel 
Maintenance and Inspection Tasks

    (f) Within 3 months after the effective date of this AD, revise 
the ALS of the Instructions for Continued Airworthiness to 
incorporate Airbus A310 ALS Part 5--Fuel Airworthiness Limitations, 
dated May 31, 2006, as defined in Airbus A310 Fuel Airworthiness 
Limitations, Document 95A.1930/05, Issue 1, dated December 19, 2005 
(approved by the European Aviation Safety Agency (EASA) on March 13, 
2006), Section 1, ``Maintenance/Inspection Tasks.'' For all tasks 
identified in Section 1 of Document 95A.1930/05, the initial 
compliance times start from the later of the times specified in 
paragraphs (f)(1) and (f)(2) of this AD, and the repetitive 
inspections must be accomplished at the intervals specified in 
Section 1 of Document 95A.1930/05, except as provided by paragraph 
(g) of this AD.
    (1) The effective date of this AD.
    (2) The date of issuance of the original French standard 
airworthiness certificate or the date of issuance of the original 
French export certificate of airworthiness.

Initial Compliance Time for Task 28-18-00-03-1

    (g) For Task 28-18-00-03-1, ``Operational check of lo-level/
underfull/calibration sensors,'' identified in Section 1, 
``Maintenance/Inspection Tasks,'' of Airbus A310 Fuel Airworthiness 
Limitations, Document 95A.1930/05, Issue 1, dated December 19, 2005: 
The initial compliance time is the later of the times specified in 
paragraphs (g)(1) and (g)(2) of this AD. Thereafter, Task 28-18-00-
03-1 must be accomplished at the repetitive interval specified in 
Section 1 of Document 95A.1930/05.
    (1) Prior to the accumulation of 40,000 total flight hours.
    (2) Within 72 months or 20,000 flight hours after the effective 
date of this AD, whichever occurs first.

Revise ALS to Incorporate CDCCLs

    (h) Within 12 months after the effective date of this AD, revise 
the ALS of the Instructions for Continued Airworthiness to 
incorporate Airbus A310 ALS Part 5--Fuel Airworthiness Limitations, 
dated May 31, 2006, as defined in Airbus A310 Fuel Airworthiness 
Limitations, Document 95A.1930/05, Issue 1, dated December 19, 2005 
(approved by the EASA on March 13, 2006), Section 2, ``Critical 
Design Configuration Control Limitations.''

No Alternative Inspections, Inspection Intervals, or CDCCLs

    (i) Except as provided by paragraph (j) of this AD: After 
accomplishing the actions specified in paragraphs (f) and (h) of 
this AD, no alternative inspections, inspection intervals, or CDCCLs 
may be used.

Alternative Methods of Compliance (AMOCs)

    (j)(1) 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.
    (2) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.

Related Information

    (k) EASA airworthiness directive 2006-0202, dated July 11, 2006, 
also addresses the subject of this AD.

    Issued in Renton, Washington, on April 11, 2007.
Stephen P. Boyd,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
 [FR Doc. E7-7518 Filed 4-19-07; 8:45 am]
BILLING CODE 4910-13-P