Discussion
We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to the specified products. That NPRM was published in the Federal Register on June 6, 2008 (73 FR 32250). That NPRM proposed to correct an unsafe condition for the specified products. The MCAI states:
One operator experienced failures of four Fuel Level Sensor- Amplifier (FLSA) and Multi Tank Indicators (MTI) units. FLSA and MTI failures have been identified as having been caused by incorrect connector sleeves material fitted to the MTI units.
Degradation of the electrical insulation sleeves of the Low- level indication lamps on the MTI on the flight deck can cause a short circuit that might result in high voltage being conveyed to the high and low level sensors in the outer tanks. This might cause the level sensor to heat above acceptable limits.
For the reasons stated above, this Airworthiness Directive (AD) requires theaccomplishment of wiring modifications to protect the FLSA and the Flight Warning Computers from 115V AC and 28V DC short circuits within the MTI.
This action is necessary to prevent overheating of the fuel level sensors, which could result in a fuel tank explosion and consequent loss of the airplane. You may obtain further information by examining the MCAI in the AD docket.
Actions Since NPRM Was Issued
Since we issued the NPRM, Airbus has issued Mandatory Service Bulletin A300-28A6096, Revision 02, dated July 4, 2008. In the NPRM, we referred to Airbus Mandatory Service Bulletin A300-28A6096, Revision 01, dated April 16, 2008, as the source of service information for doing the modification. The procedures in Airbus Mandatory Service Bulletin A300-28A6096, Revision 02, dated July 4, 2008, are essentially the same as those in Airbus Mandatory Service Bulletin A300-28A6096, Revision 01, dated April 16, 2008. Therefore, we have revised paragraph (f) of this AD to refer to Airbus Mandatory Service Bulletin A300- 28A6096, Revision 02, dated July 4, 2008, as the appropriate source of service information for doing the modification, and to give credit for using Airbus Mandatory Service Bulletin A300-28A6096, Revision 01, dated April 16, 2008, for accomplishing the modification before the effective date of the AD.
Comments
We gave the public the opportunity to participate in developing this AD. We considered the comments received.
Request To Delay Issuance of AD
Air Transport Association (ATA), on behalf of its member American Airlines (AA), and UPS and FedEx ask that we delay issuance of the AD until the master minimum equipment list (MMEL) can be revised to support the low-level warning configuration. AA, UPS, and FedEx state that disconnection of the low-level warning for the left and right outer fuel tanks requires significant changes to the Airbus A300-600 MMEL. AA, UPS, and FedEx add that the current MMEL available to U.S. operators cannot support the disconnected low-level warning configuration; therefore, the AD should not be released until the MMEL has been revised.
We disagree with the commenter's request and rationale for delaying issuance of the AD. Revision 16 of the MMEL, dated October 2008, has been released and is available to U.S. operators. Revision 16 of the MMEL supports the low-level warning configuration. Therefore, we have made no change to the AD in this regard.
Request To Extend Compliance Time
ATA, on behalf of its member AA, and UPS and FedEx ask that we revise the compliance time specified in the NPRM from 90 to 180 days to allow FAA approval of the air carrier's customized MEL after it has been revised, and to facilitate distribution.
We disagree with the commenters. As stated above, the revised MMEL has been released and is available to air carriers. We have determined that the 3-month compliance time specified in this AD is adequate to address the unsafe condition in a timely manner. We have made no change to the AD in this regard.
Request To Include Alternate Terminating Action
ATA on behalf of its member AA, and UPS and FedEx ask that the AD include alternative terminating action for operators that install multi-task indicators (MTIs) that have been modified per Smiths Service Bulletin 1410KID-28-468, and installed per Airbus Mandatory Service Bulletin A300-28-6101, dated June 4, 2008. AA and FedEx state that once the MTI is modified the unsafe condition specified in the NPRM will be addressed. UPS states that the improved sleeve installed per Airbus Mandatory Service Bulletin A300-28-6101, dated June 4, 2008, addresses the concerns in the NPRM.
We disagree with the commenters. Based on information provided by Airbus, Airbus Mandatory Service Bulletin A300-28-6101, dated June 4, 2008, does not contain a final fix for the unsafe condition specified in the AD. Airbus is currently developing two modifications that provide the final solution to address the unsafe condition identified in this AD. Once these modifications are developed, approved, and available, we might consider additional rulemaking which would terminate the AD requirements. We have made no change to the AD in this regard.
Conclusion
We reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the change described previously. We determined that this change will not increase the economic burden on any operator or increase the scope of the AD.
Differences Between This AD and the MCAI or Service Information
We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.
We might also have required different actions in this AD from those in the MCAI in order to follow our FAA policies. Any such differences are highlighted in a NOTE within the AD.
Costs of Compliance
We estimate that this AD will affect 151 products of U.S. registry. We also estimate that it will take about 5 work-hours per product to comply with the basic requirements of this AD. The average labor rate is $80 per work-hour. Required parts will cost about $0 per product. Where the service information lists required parts costs that are covered under warranty, we have assumed that there will be no charge for these parts. As we do not control warranty coverage for affected parties, some parties may incur costs higher than estimated here. Based on these figures, we estimate the cost of this AD to the U.S. operators to be $60,400, or $400 per product.
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 determined that this AD will not have federalism implications under Executive Order 13132. This AD 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.
For the reasons discussed above, I certify this AD:
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 AD and placed it in the AD docket.
Examining the AD Docket
You may examine the AD docket on the Internet at http:// www.regulations.gov; or in person at the Docket Operations office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The AD docket contains the NPRM, the regulatory evaluation, any comments received, and other information. Thestreet address for the Docket Operations office (telephone (800) 647-5527) is in the ADDRESSES section. Comments will be available in the AD docket shortly after receipt.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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 AD: