AD 97-08-03

This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A310 and A300-600 series airplanes, that requires a functional flow test and leak test to verify if the pressure reducing valve in the cargo fire extinguishing system is in a serviceable condition, and replacement of any faulty valve with a new valve prior to extended range twin-engine operations of the airplane. This amendment is prompted by a report that, during a scheduled maintenance check, an inoperative pressure reducing valve was found in the cargo fire extinguishing system. The actions specified by this AD are intended to ensure that a faulty pressure reducing valve is not installed, which could result in reduced fire protection of the cargo compartment of the airplane.

Final rule.

97-08-03 AIRBUS INDUSTRIE: Amendment 39-9991. Docket 94-NM-196-AD.

Applicability: Model A310 and A300-600 series airplanes on which Airbus Modification 6403 (reference Airbus Service Bulletin A310-26-2010 or A300-600-26-6011) has been installed; certificated in any category.

NOTE 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it otherwise 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 use the authority provided in paragraph (b) of this AD to request approval from the FAA. This approval may address either no action, if the current configuration eliminates the unsafe condition; or different actions necessary to address the unsafe condition described in this AD. Such a request should include an assessment of the effectof the changed configuration on the unsafe condition addressed by this AD. In no case does the presence of any modification, alteration, or repair remove any airplane from the applicability of this AD.

Compliance: Required as indicated, unless accomplished previously.

To ensure that a faulty pressure reducing valve in the cargo fire extinguishing system is not installed, which could result in reduced fire protection of the cargo compartment of the airplane from 260 minutes to 60 minutes, accomplish the following:

(a) Prior to the accumulation of 600 total flight hours after the effective date of this AD, perform a functional flow test and leak test to verify if the pressure reducing valve in the cargo fire extinguishing system is in a serviceable condition, in accordance with paragraph 4.2., Description, of Airbus All Operators Telex AOT 26-13, dated June 28, 1994. If a faulty pressure reducing valve is installed, prior to extended range twin-engine operations (ETOPS),replace it with a new valve, in accordance with the aircraft maintenance manual, reference 26-23-14, Page block 401.

(b) 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.

(c) 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.

(d) The tests shall be done in accordance with Airbus All Operators Telex AOT 26- 13, dated June 28, 1994. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Airbus Industrie, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

(e) This amendment becomes effective on May 15, 1997.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Airbus Model A310 and A300-600 series airplanes was published in the Federal Register on September 7, 1995 (60 FR 46541). That action proposed to require a functional flow test and leak test to verify if the pressure reducing valve in the cargo fire extinguishing system is in a serviceable condition.

Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the comments received.

Support for the Proposal
One commenter supports the proposed AD.

Request to Make AD Effective Immediately
One commenter supports the intent of the proposed rule, but opposes the FAA's method of issuing the rule by providing time for prior notice and public comment. This commenter considers that the potential unsafe condition regarding thefire extinguishing systems that qualify an airplane for extend range twin-engine operation (ETOPS) flights should have been issued as an immediately adopted rule. Further, the commenter contends that the AD should prohibit extended ETOPS operation beyond 60 minutes, and include a temporary revision to the Airplane Flight Manual (AFM) alerting the crew of the a potentially unsafe condition should a fire exist. Terminating action for the restricted operation and AFM revision should be authorized after compliance with the inspection and replacement criteria of the AD. The commenter maintains that the seriousness of a cargo fire during ETOPS operation mandates such action.

While the FAA recognizes the urgency of safety measures to ensure that fire does not present an unsafe condition onboard an airplane, the FAA does not concur with the commenter's suggestion that notice and time for public comment should have been waived for this rulemaking action. The FAA conducted a review of the characteristics of the failure mode relative to the subject pressure valve and concluded that the safety implications did not warrant rulemaking without the opportunity for public participation. The airplane on which the inoperative pressure reducing valve was found was not approved for ETOPS operations. Further, at the time the notice was issued, there were no U.S.-registered Model A300-600 or A310 series airplanes that were approved for ETOPS operations. The consequences of the subject faulty valve are not as critical for non-ETOPS operations, since other the additional fire extinguishing features of the system can address problems that occur within a typical flight range (or 60 minutes).

Conclusion
After careful review of the available data, including the comments noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact
The FAA estimates that 48 Airbus Model A310 and A300-600 series airplanes of U.S. registry will be affected by this AD, that it will take approximately 1 work hour per airplane to accomplish the required actions, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $2,880, or $60 per airplane.

The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact
The regulations adopted herein will 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 final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under 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. A final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES."

List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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.
39.13 - [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: