AD 99-06-06

This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A310 and A300-600 series airplanes, that requires repetitive flow checks of the hydraulic pump drain system to ensure that the system is not clogged, and correction of any discrepancy. This amendment also requires replacement of the existing magnetic seals of the accessory gearbox assembly with new, improved seals. Replacement of certain seals terminates the requirement for repetitive flow checks. This amendment also requires replacement of the engine drain modules with drain manifolds. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent contamination of the engine accessory gearbox oil with hydraulic fluid, which could result in an in-flight engine shutdown.

Final rule.

99-06-06 AIRBUS INDUSTRIE: Amendment 39-11070. Docket 96-NM-66-AD.

Applicability: Model A310 and A300-600 series airplanes; equipped with General Electric CF6-80C2 engines; except those airplanes on which Airbus Modifications 8952 and 10401, or Airbus Modification 10656 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 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 (f) 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 contamination of the engine accessory gearbox oil with hydraulic fluid, which could result in an in-flight engine shutdown, accomplish the following:

(a) For airplanes on which Airbus Modification 8952 has not been installed: Within 30 days after the effective date of this AD, perform a flow check of the hydraulic pump drain system to ensure that the system is not clogged and, prior to further flight, correct any discrepancies, in accordance with either paragraph (a)(1) or (a)(2) of this AD, as applicable. Repeat the flow check thereafter at intervals not to exceed 500 flight hours until the modification required by paragraph (b) of this AD is accomplished.

(1) For Model A310 series airplanes: Perform the flow checks and correct any discrepancy in accordance with Airbus Service Bulletin A310-72-2020, Revision 2,dated January 13, 1993.

NOTE 2: Flow checks and corrective actions accomplished prior to the effective date of this AD in accordance with the original issue of Airbus Service Bulletin A310-72-2020, dated September 14, 1992, or Revision 1, dated November 25, 1992, are considered acceptable for compliance with paragraph (a)(1) of this AD.

(2) For Model A300-600 series airplanes: Perform the flow checks and correct any discrepancy in accordance with Airbus Service Bulletin A300-72-6016, Revision 2, dated January 13, 1993.

NOTE 3: Flow checks and corrective actions accomplished prior to the effective date of this AD in accordance with Airbus Service Bulletin A300-72-6016, dated September 14, 1992, are considered acceptable for compliance with paragraph (a)(2) of this AD.

(b) For airplanes on which Airbus Modification 8952 has not been installed and that are not operating under extended range twin-engine operations (ETOPS): Within 3 months after the effective date of this AD, replace (on both engines) the existing magnetic seal of the green hydraulic system on the accessory gearbox assembly with a new, improved spring-loaded seal and ring assembly, in accordance with either paragraph (b)(1) or (b)(2) of this AD, as applicable. Accomplishment of this replacement constitutes terminating action for the repetitive flow check requirements specified in paragraph (a) of this AD.

(1) For Model A310 series airplanes: Accomplish the replacement in accordance with Airbus Service Bulletin A310-72-2017, Revision 3, dated August 6, 1993.

(2) For Model A300-600 series airplanes: Accomplish the replacement in accordance with Airbus Service Bulletin A300-72-6013, Revision 3, dated August 6, 1993.

(c) For airplanes on which Airbus Modification 8952 has not been installed and that are operating under ETOPS: Within 10 days after the effective date of this AD, replace (on both engines) the existing magnetic seal of the green hydraulic system on the accessory gearbox assembly with a new, improved spring-loaded seal and ring assembly, in accordance with either paragraph (c)(1) or (c)(2) of this AD, as applicable. Accomplishment of this replacement constitutes terminating action for the repetitive flow check requirements specified in paragraph (a) of this AD.

(1) For Model A310 series airplanes: Accomplish the replacement in accordance with Airbus Service Bulletin A310-72-2017, Revision 3, dated August 6, 1993.

(2) For Model A300-600 series airplanes: Accomplish the replacement in accordance with Airbus Service Bulletin A300-72-6013, Revision 3, dated August 6, 1993.

(d) For airplanes on which Airbus Modifications 8952 and 10401 have not been installed: Within 18 months after the effective date of this AD, replace (on both engines) the existing magnetic seals of the yellow and blue hydraulic systems, the starter, and the integrated drive generator on the accessory gearbox assembly with new, improved spring-loaded seal and ring assemblies, in accordance with either paragraph (d)(1) or (d)(2) of this AD, as applicable. Accomplishment of this replacement constitutes terminating action for the repetitive flow check requirements specified in paragraph (a) of this AD.

(1) For Model A310 series airplanes: Accomplish the replacement in accordance with Airbus Service Bulletin A310-72-2031, dated July 24, 1995, as revised by Change Notice O.A., dated October 12, 1995.

(2) For Model A300-600 series airplanes: Accomplish the replacement in accordance with Airbus Service Bulletin A300-72-6027, dated July 24, 1995.

(e) For airplanes on which Airbus Modification 10656 has not been installed: Within 5 years after the effective date of this AD, replace the drain modules with drain manifolds in accordance with either paragraph (e)(1) or (e)(2) of this AD, as applicable.

(1) For Model A310 series airplanes: Accomplish the replacement in accordance with Airbus Service Bulletin A310-72-2029, Revision 1, dated June 22, 1995, as revised by Change Notice 1.A., dated March 13, 1997, and Change Notice 1.B., dated June 16, 1997.

(2) For Model A300-600 series airplanes: Accomplish the replacement in accordance with Airbus Service Bulletin A300-72-6025, Revision 1, dated June 22, 1995.

(f) 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, International Branch, ANM-116, 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, International Branch, ANM-116.

NOTE 4: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.

(g) 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.

(h) The actions shall be done in accordance with the following Airbus Service Bulletins, as applicable, which contain the specified effective pages:

Service Bulletin
Referenced and
Date
Page Number
Revision Level
Shown on Page
Date Shown on
Page
A310-72-2020,
Revision 2,
January 13, 1993
1-3

5-9
2

Original
January 13, 1993

September 14, 1992
A300-72-6016,
Revision 2,
January 13, 1993
1, 2

3-7
2

Original
January 13, 1993

September 14, 1992
A310-72-2017,
Revision 3,
August 6, 1993
1-9
3
August 6, 1993
A300-72-6013,
Revision 3,
August 6, 1993
1-9
3
August 6, 1993
A310-72-2031,
July 24, 1995
1-11
Original
July 24, 1995
A310-72-2031,
Change Notice O.A.,
October 12, 1995
1
Original
October 12, 1995
A300-72-6027,
July 24, 1995
1-11
Original
July 24, 1995
A310-72-2029,
Revision 1,
June 25, 1995
1, 5, 6

2-4, 7-9
1

Original
June 25, 1995

December 14, 1994
A310-72-2029,
Change Notice 1.A.,
March 13, 1997
1
Original
March 13, 1997
A310-72-2029,
Change Notice 1.B.,
June 16, 1997
1-2
Original
June 16, 1997
A300-72-6025,
Revision 1,
June 22, 1995
1, 4

2, 3, 5-7
1

Original
June 22, 1995

December 14, 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.

NOTE 5: The subject of this AD is addressed in French airworthiness directives 92-230- 135(B) R1, dated October 13, 1993; 95-183-185(B), dated September 27, 1995; and 95-184- 186(B), dated September 27, 1995.

(i) This amendment becomes effective on April 16, 1999.

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 December 17, 1998 (63 FR 69571). That action proposed to require repetitive flow checks of the hydraulic pump drain system to ensure that the system is not clogged, and correction of any discrepancy. That action also proposed to require replacement of the existing magnetic seals of the accessory gearbox assembly with new, improved seals. Replacement of certain seals would terminate the requirement for repetitive flow checks. That action also proposed to require replacement of the engine drain modules with drain manifolds.

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

Request to Revise Cost Impact Information
One commenter states that the cost to be incurred by the replacement of the engine drain modules with drain manifolds will greatly exceed the cost specified in the proposal.

The FAA infers that the commenter is requesting that the cost estimate be revised in the final rule. The FAA does not concur. The FAA acknowledges that the cost impact information, below, describes only the"direct" costs of the specific actions required by this AD. The estimate of 16 hours necessary to accomplish the required actions was provided to the FAA by the manufacturer, and represents the time necessary to perform only the actions actually required by this AD. The FAA recognizes that, in accomplishing the requirements of any AD, operators may incur"incidental" costs in addition to the"direct" costs. The cost analysis in AD rulemaking actions, however, typically does not include incidental costs, such as the time required to gain access and close up; planning time; or time necessitated by other administrative actions. Because incidental costs may vary significantly from operator to operator, they are almost impossible to calculate. Therefore, attempting to estimate such costs would be futile. No change to the final rule is necessary.

Conclusion
After careful review of the available data, including the comment 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 64 airplanes of U.S. registry will be affected by this AD.

It will take approximately 3 work hours per airplane to accomplish the required flow checks, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the flow checks required by this AD on U.S. operators is estimated to be $11,520, or $180 per airplane, per flow check cycle.

It will take approximately 24 work hours per airplane (12 work hours per engine) to accomplish the required replacement of the magnetic seals with spring-loaded seal and ring assemblies, at an average labor rate of $60 per work hour. Required parts for this replacement will cost approximately $12,000 per airplane. Based on these figures, the cost impact of this replacement required by this AD on U.S. operators is estimated to be $860,160, or $13,440 per airplane.

It will take approximately 16 work hours per airplane (8 work hours per engine) to accomplish the replacement of the drain modules with drain manifolds, at an average labor rate of $60 per work hour. Required parts for this replacement will cost approximately $13,200 per airplane. Based on these figures, the cost impact of this replacement required by this AD on U.S. operators is estimated to be $906,240, or $14,160 per airplane.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actionsin 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 containedin 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: