AD 97-21-04

This amendment adopts a new airworthiness directive (AD), applicable to certain Airbus Model A310 and A300-600 series airplanes, that requires flow checks of the hydraulic pump drain system to ensure that the system is not clogged, and correction of any discrepancy. Additionally, this amendment requires replacement of the existing seal of the accessory gearbox with a new, improved seal assembly; this replacement terminates the requirement for repetitive flow checks. This amendment is prompted by reports indicating that hydraulic fluid had contaminated the engine oil system as a result of failure of the seal of the hydraulic pump shaft. The actions specified by this AD are intended to prevent clogging of the hydraulic pump drain system, which could cause failure of the seal of the hydraulic pump shaft and subsequent contamination of the engine accessory gearbox oil; this condition could result in an in-flight engine shutdown.

Final rule.

97-21-04 AIRBUS: Amendment 39-10157. Docket 96-NM-64-AD.

Applicability: Model A300B4-620, -622, -622R, and A300C4-620; and Model A310-221, -222, -322, -324, and -325 series airplanes; equipped with Pratt & Whitney turbofan engines; on which Airbus Modification 10399 or 10400 has not been accomplished; 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 (c) 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 clogging of the hydraulic pump drain system, which could cause failure of the seal of the hydraulic pump shaft and subsequent contamination of the engine accessory gearbox oil, and could result in an in-flight engine shutdown, accomplish the following:

(a) Within 30 days after the effective date of this AD, perform a flow check of the hydraulic pump drain system to ensure that it 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 discrepancies in accordance with Airbus Service Bulletin A310-72-2022, dated February 16, 1993 (for airplanes on which Pratt & Whitney JT9D-7R4D1 and -7R4E1 engines are installed); or Airbus Service Bulletin A310-72-2023, Revision 1, dated December 22, 1993 (for airplanes on which Pratt & Whitney PW4152 and PW4156A engines are installed); as applicable.

NOTE 2: Flow checks accomplished prior to the effective date of this AD in accordance with the original issuance of Airbus Service Bulletin A310-72-2023 are considered acceptable for compliance with the applicable action specified in this AD.

(2) For Model A300-600 series airplanes: Perform the flow checks and correct discrepancies in accordance with Airbus Service Bulletin A300-72-6018, Revision 1, dated December 22, 1993, as revised by Service Bulletin Change Notice No. O.A., dated June 17, 1993 (for airplanes on which Pratt & Whitney JT9D-7R4H1 engines are installed); or Airbus Service Bulletin A300-72-6019, Revision 1, dated December 22, 1993, as revised by Service Bulletin Change Notice No. O.A., dated June 17, 1993 (for airplanes on which Pratt & Whitney PW4158 engines are installed); as applicable.

NOTE 3: Flow checks accomplished prior to the effective date of this AD in accordance with the original issuance of Airbus Service Bulletin A300-72-6018 or Airbus Service Bulletin A300-72-6019 are considered acceptable for compliance with the applicable action specified in this AD.

(b) Within 12 months after the effective date of this AD, replace (on both engines) the existing seal of the green hydraulic system gearbox with a new, improved seal assembly in accordance with either paragraph (b)(1) or (b)( 2) of this AD, as applicable. Accomplishment of this replacement terminates the repetitive flow check requirements for this AD.

(1) For Model A310 series airplanes: Accomplish the replacement in accordance with Airbus Service Bulletin A310-72-2018, Revision 2, dated December 22, 1993 (for airplanes on which Pratt & Whitney PW JT9D-7R4D1 and-7R4E1 engines are installed); or Airbus Service Bulletin A310-72-2019, Revision 2, dated December 22, 1993 (for airplanes on which Pratt & Whitney PW4152 and PW4156A engines are installed); as applicable.

NOTE 4: Replacement of the existing seal on the green hydraulic system gearbox with a new, improved seal assembly accomplished prior to the effective date of this AD, in accordance with the original issuance or Revision 1 of Airbus Service Bulletin A310-72-2019, or with the original issuance or Revision 1 of Airbus Service A310-72-2018, is considered acceptable for compliance with the applicable action specified in this AD.

(2) Model A300-600 series airplanes: Accomplish the replacement in accordance with Airbus Service Bulletin A300-72-6014, dated March 15, 1993 (for airplanes on which Pratt & Whitney PW JT9D-7R4H1 engines are installed); or Airbus Service Bulletin A300-72-6015, dated March 15, 1993 (for airplanes on which Pratt & Whitney PW4158 engines are installed); asapplicable.

(c) 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 5: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Standardization Branch, ANM-113.

(d) 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.

(e) The actions shall be done in accordance with the following Airbus service bulletins, as applicable, which include the specified effective pages:

Service Bulletin
Number

Page Number
Revision Level
Shown on Page
Date
Shown on Page
A310-72-2022,
February 16, 1993
1-7
Original
February 16, 1993
A310-72-2023,
Revision 1,
December 22, 1993
1, 2, 4-6

3, 7
1

Original
December 22, 1993

February 16, 1993
A300-72-6018,
Revision 1,
December 22, 1993
1, 2, 4

3, 5-7
1

Original
December 22, 1993

February 16, 1993
A300-72-6018,
Service Bulletin
Change Notice
No. O.A., June 17, 1993
1
Original
June 17, 1993
A300-72-6019,
Revision 1,
December 22, 1993
1-6

7
1

Original
December 22, 1993

February 16, 1993
A300-72-6019,
Service Bulletin
Change Notice
No. O.A., June 17, 1993
1-2
Original
June 17, 1993
A310-72-2018,
Revision 2,
December 22, 1993
1-3, 5-7

4, 9

8
2

Original

1
December 22, 1993

March 15, 1993

August 6, 1993
A310-72-2019,
Revision 2,
December 22, 1993
1-3, 5-7

4, 9

8
2

Original

1
December22, 1993

March 15, 1993

August 6, 1993
A300-72-6014,
March 15, 1993
1-7
Original
March 15, 1993
A300-72-6015,
March 15, 1993
1-9
Original
March 15, 1993

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.

(f) This amendment becomes effective on November 24, 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 February 18, 1997 (62 FR 7184). 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. Additionally, the action proposed to require replacement of the existing seal of the accessory gearbox with a new, improved seal assembly. This replacement, when accomplished, would provide terminating action for the repetitive flow checks.

Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were submitted in response to the proposal or the FAA's determination of the cost to the public.

References to Service Bulletin Change Notices
Since the issuance of the proposal, Airbus has issued Service Bulletin Change Notice No. O.A., dated June 17, 1993, for Airbus Service Bulletin A300-72-6018 (for Model A300-600 series airplanes equipped with Pratt & Whitney JT9D-7R4 engines). This change notice revises the service bulletin by specifying the latest French airworthiness directive: 92-231-136(B)R1, dated March 27, 1993.

Airbus also has issued Service Bulletin Change Notice No. O.A., dated June 17, 1993, for Airbus Service Bulletin A300-72-6019 (for Model A300-600 series airplanes equipped with Pratt & Whitney PW 4000 engines). This change notice also revises the service bulletin by referencing the French airworthiness directive specified previously. Additionally, the change notice revises the service bulletin effectivity by specifying the operators of airplanes having certain manufacturer s serial numbers.

The FAA has revised the final rule to include references to these service bulletin change notices.

Conclusion
After carefulreview of the available data, the FAA has determined that air safety and the public interest require the adoption of the rule with the changes previously described. The FAA has determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.

Cost Impact
The FAA estimates that 3 Airbus Model A300-600 and A310 series airplanes of U.S. registry will be affected by this AD, that it will take approximately 3 work hours per airplane to accomplish the required one-time inspection, and that the average labor rate is $60 per work hour. It will take approximately 10 work hours per airplane to accomplish the required terminating modification, at an average labor rate of $60 per work hour. Required parts will cost approximately $1,500 per airplane. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be $6,840, or $2,280 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: