AD 2007-18-04

We are superseding an existing airworthiness directive (AD) for the products listed above. This AD results from mandatory continuing airworthiness information (MCAI) originated by an aviation authority of another country to identify and correct an unsafe condition on an aviation product. The MCAI describes the unsafe condition as:

Two A330 operators have reported uncontained APU (auxiliary power unit) generator failures on ground.
Preliminary investigations confirmed an uncontained APU Generator failure with subsequent aircraft structural damages to the APU compartment and, in one case, to the stabiliser compartment.

Loose APU generator parts can lead to damage to the APU fire wall which might reduce its fire extinguishing capability, possibly leading to a temporary uncontrolled fire which constitutes an unsafe condition.
* * * * *

This AD requires actions that are intended to address the unsafe condition described in the MCAI.

DATES: This AD becomes effective September 14, 2007.

The Director of the Federal Register approved the incorporation by reference of certain publications listed in the AD as of September 14, 2007.

On June 26, 2007 (72 FR 31973, June 11, 2007), the Director of the Federal Register approved the incorporation by reference of certain other publications.

We must receive comments on this AD by October 1, 2007.

Final rule; request for comments.

2007-18-04 Airbus: Amendment 39-15184. Docket No. FAA-2007-29073; Directorate Identifier 2007-NM-178-AD.

Effective Date

(a) This airworthiness directive (AD) becomes effective September 14, 2007.

Affected ADs

(b) This AD supersedes AD 2007-12-10.

Applicability

(c) This AD applies to Airbus Model A330 and A340 airplanes; certificated in any category; all certified models, all serial numbers.

Subject

(d) Air Transport Association (ATA) of America Code 24: Electrical power.

Reason

(e) The mandatory continued airworthiness information (MCAI) states:

Two A330 operators have reported uncontained APU (auxiliary power unit) generator failures on ground.

Preliminary investigations confirmed an uncontained APU Generator failure with subsequent aircraft structural damages to the APU compartment and, in one case, to the stabilizer compartment.

Loose APU generator parts can lead to damage to the APU fire wall which might reduce its fireextinguishing capability, possibly leading to a temporary uncontrolled fire which constitutes an unsafe condition.

Further detailed investigations are ongoing to determine the root causes. It has been evidenced that for both events, this unknown root cause initiates a collapse of the Drive End Bearing (DEB) leading to an uncontained failure. Evidence shows also that the DEB failures were not instantaneous, and therefore, the detection of small debris could indicate an early stage of DEB failure.

A one-time inspection for detection of large-scale debris in the Generator Scavenge inlet screen (last chance filter) of the APU allowing to identify APU Generator in a state close to failure has been rendered mandatory by Airworthiness Directive (AD) 2007-0080-R1 [that AD corresponds to FAA AD 2007-12-10].

The original Emergency Airworthiness Directive (AD) 2007-0188-E mandated a repetitive inspection of the APU Generator Scavenge filter element and filter housing and APU Generator Drain plug for signs of small debris coming from the APU Generator and therefore to detect any APU Generator failure in an early stage.

The corrective action includes retaining the requirements of the existing AD (a one-time inspection of the inlet screen and, for certain airplanes, a check of the differential pressure indicator button, and applicable corrective actions). The corrective action adds repetitive inspections of the APU Generator scavenge oil filter element and housing and the APU Generator drain plug for signs of metallic debris, and applicable corrective actions. Those corrective actions include shipping the debris to Airbus or Goodrich. The corrective actions also include the following: Replacing the APU generator scavenge oil filter for airplanes on which metallic debris is found; inspecting the inside filter element and outer diameter of the filter housing for damage to the packing and replacing the packing if damaged; cleaning the generator drain plug and reinstalling the plug with a new seal for airplanes on which no metallic debris or metallic debris within acceptable criteria is found; or keeping the APU inoperative.

Restatement of Requirements of AD 2007-12-10

(f) Unless already done, do the following actions.

(1) For airplanes on which the date of issuance of the original French standard airworthiness certificate or the date of issuance of the original French export certificate of airworthiness is before March 1, 2007: Within 63 days after June 26, 2007, in accordance with the instructions of Airbus All Operators Telex (AOT) A330- 24A3042, A340-24A4056, or A340-24A5020, all Revision 02, all dated April 12, 2007; as applicable: Inspect the inlet screen (last chance filter) for the generator scavenge-oil pump for signs of debris and, as applicable, apply all associated corrective actions before further flight.

(2) For Model A330 aircraft operating under MMEL (master minimum equipment list) Item 24-22-01 "AC Main Generation'' or MMEL Item 36-11-01 "Bleed Air Supply System Failure'' and on which the date of issuance of the original French standard airworthiness certificate or the date of issuance of the original French export certificate of airworthiness is before March 1, 2007: As of June 26, 2007, before each flight, perform a check of the differential pressure indicator button on the lube filter and the generator scavenge filter in accordance with the instructions of Airbus AOT A330-24A3042, Revision 02, dated April 12, 2007, until accomplishment of paragraph (g)(5) of this AD.

Note 1: The repetitive checks before each flight specified in paragraph (f)(2) of this AD are not required for airplanes operated under MMEL Item 36-11-01, provided the APU generator has been removed or deactivated in accordance with the instructions of Airbus AOT A330- 24A3042, Revision 02, dated April 12, 2007.

(3) Actions done before June 26, 2007, in accordance with the applicable Airbus service informationin Table 1 of this AD are acceptable for compliance with the corresponding provisions of paragraph (f) of this AD.

Table 1.--Acceptable Earlier Revisions of Service Information

Airbus All Operators Telex
Revision Level
Date
A330-24A3042
Original
March 22, 2007
A330-24A3042
01
March 29, 2007
A340-24A4056
Original
March 22, 2007
A340-24A4056
01
March 29, 2007
A340-24A5020
Original
March 22, 2007
A340-24A5020
01
March 29, 2007

New Requirements of This AD: Actions and Compliance

(g) Unless already done, do the following actions.

(1) For airplanes on which the date of issuance of the original French standard airworthiness certificate or the date of issuance of the original French export certificate of airworthiness is on or before July 1, 2007: Within 30 days after the effective date of this AD, in accordance with the instructions of paragraph 4.2.1 of the applicable Airbus service information specified in Table 2 of this AD: Clean and inspect theAPU Generator scavenge oil filter element and housing and inspect the APU generator drain plug to detect metallic debris, and apply all applicable associated corrective actions before further flight.

Table 2.--Service Information

Airbus All Operators Telex
Revision Level
Date
A330-24A3044
01
July 20, 2007
A340-24A4057
02
August 14, 2007
A340-24A5021
01
July 20, 2007

(2) Within 450 aircraft flight hours or 200 APU operating hours, whichever occurs later, after accomplishing the inspection required by paragraph (g)(1) of this AD, in accordance with the instructions of paragraph 4.2.2 of the applicable Airbus service information specified in Table 2 of this AD: Inspect the APU generator scavenge oil filter element and housing and the APU generator drain plug to detect metallic debris; and apply all applicable associated corrective actions before further flight. Repeat the inspections thereafter at intervals not to exceed 450 aircraft flight hours or 200 APU operating hours, whichever occurs later.
(3) For airplanes on which the date of issuance of the original French standard airworthiness certificate or the date of issuance of the original French export certificate of airworthiness is after July 1, 2007: Within 450 aircraft flight hours or 200 APU operating hours after the effective date of this AD, whichever occurs later, in accordance with the instructions of paragraph 4.2.2 of the applicable Airbus service information specified in Table 2 of this AD: Inspect the APU generator scavenge oil filter element and housing and the APU generator drain plug to detect metallic debris; and apply all applicable associated corrective actions before further flight. Repeat the inspections thereafter at intervals not to exceed 450 aircraft flight hours or 200 APU operating hours, whichever occurs later.
(4) Actions done before the effective date of this AD, in accordance with the applicable Airbus service information in Table 3 of this AD are acceptable for compliance with the corresponding provisions of paragraph (g) of this AD.

Table 3.--Acceptable Earlier Revisions of Service Information

Airbus All Operators Telex
Revision Level
Date
A330-24A3044
Original
July 5, 2007
A340-24A4057
Original
July 5, 2007
A340-24A4057
01
July 20, 2007
A340-24A5021
Original
July 5, 2007

(5) For Model A330 aircraft operating under MMEL Item 24-22-01, "AC Main Generation,'' or MMEL Item 36-11-01, "Bleed Air Supply System Failure'': Unless the APU generator has been deferred in accordance with the MMEL by deactivation (quill shaft removed) or removal, the inspection required by paragraph (g)(2) or (g)(3), as applicable, of this AD must be performed prior to the first flight of the specified MMEL repair time interval. Accomplishing the actions in this paragraph terminates the actions required by paragraph (f)(2) of this AD.

Note 2: For A330 aircraft, MMEL Item 24-22-01 (AC Main Generation) and/or MMEL Item 36-11-01 (Bleed Air Supply System Failure) require that the APU be used during the entire flight.

FAA AD Differences

Note 3: This AD differs from the MCAI and/or service information as follows: No differences.

Other FAA AD Provisions

(h) The following provisions also apply to this AD:

(1) Alternative Methods of Compliance (AMOCs): The Manager, International Branch, Transport Airplane Directorate, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. Send information to ATTN: Tim Backman, Aerospace Engineer, International Branch, ANM-116, Transport Airplane Directorate, FAA, 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 227-2797; fax (425) 227-1149. 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.

(2) Airworthy Product: For any requirement in this AD to obtain corrective actions from a manufacturer or other source, use these actions if they are FAA-approved. Corrective actions are considered FAA-approved if they are approved by the State of Design Authority (or their delegated agent). You are required to assure the product is airworthy before it is returned to service.

(3) Reporting Requirements: For any reporting requirement in this AD, under the provisions of the Paperwork Reduction Act, the Office of Management and Budget (OMB) has approved the information collection requirements and has assigned OMB Control Number 2120- 0056.

Related Information

(i) Refer to Mandatory Continuing Airworthiness Information (MCAI) European Aviation Safety Agency (EASA) Airworthiness Directive (EAD) 2007-0188R1, dated July 24, 2007, and the AOTs specified in Table 2 of this AD, for related information.

Material Incorporated by Reference

(j) You must use the applicable Airbus service information specified in Table 4 of this AD to do the actions required by this AD, unless the AD specifies otherwise. (Only the first page of these documents contains the document number, revision level, and date; no other pages of these documents contain this information.)

(1) The Director of the Federal Register approved the incorporation by reference of the Airbus service information specified in Table 5 of this AD under 5 U.S.C. 552(a) and 1 CFR part 51.

(2) The Director of the Federal Register previously approved the incorporation by reference of the Airbus service information specified in Table 6 of this AD on June 26, 2007 (72 FR 31973, June 11, 2007).

(3) For service information identified in this AD, contact Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France.
(4) You may review copies at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the National Archives and Records Administration (NARA). For information on the availability ofthis material at NARA, call (202) 741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html .

Table 4.--All Material Incorporated by Reference

Airbus All Operators Telex
Revision Level
Date
A330-24A3042
02
April 12, 2007
A330-24A3044
01
July 20, 2007
A340-24A4056
02
April 12, 2007
A340-24A4057
02
August 14, 2007
A340-24A5020
02
April 12, 2007
A340-24A5021
01
July 20, 2007

Table 5.--New Material Incorporated by Reference

Airbus All Operators Telex
Revision Level
Date
A330-24A3044
01
July 20, 2007
A340-24A4057
02
August 14, 2007
A340-24A5021
01
July 20, 2007

Table 6.--Material Previously Incorporated by Reference

Airbus All Operators Telex
Revision Level
Date
A330-24A3042
02
April 12, 2007
A340-24A4056
02
April 12, 2007
A340-24A5020
02
April 12, 2007

Discussion

On May 30, 2007, we issued AD 2007-12-10, Amendment 39-15088 (72 FR 31973, June 11, 2007). That AD required actions intended to address an unsafe condition on the products listed above.

Since we issued AD 2007-12-10, it has been determined that the drive end bearing (DEB) failures did not occur instantly, and small debris in the filter could be detected before collapse of the DEB. The one-time inspection mandated by AD 2007-12-10 only detects large debris.

The European Aviation Safety Agency (EASA), which is the Technical Agent for the Member States of the European Community, has issued EASA Airworthiness Directive (EAD) 2007-0188R1, dated July 24, 2007 (referred to after this as "the MCAI''), to correct an unsafe condition for the specified products. The MCAI states:

Two A330 operators have reported uncontained APU (auxiliary power unit) generator failures on ground.

Preliminary investigations confirmed an uncontainedAPU Generator failure with subsequent aircraft structural damages to the APU compartment and, in one case, to the stabiliser compartment.

Loose APU generator parts can lead to damage to the APU fire wall which might reduce its fire extinguishing capability, possibly leading to a temporary uncontrolled fire which constitutes an unsafe condition.

Further detailed investigations are ongoing to determine the root causes. It has been evidenced that for both events, this unknown root cause initiates a collapse of the Drive End Bearing (DEB) leading to an uncontained failure. Evidence shows also that the DEB failures were not instantaneous, and therefore, the detection of small debris could indicate early stage of DEB failure.

A one-time inspection for detection of large-scale debris in the Generator Scavenge inlet screen (last chance filter) of the APU allowing to identify APU Generator in a state close to failure has been rendered mandatory by Airworthiness Directive (AD) 2007-0080-R1 [that AD corresponds to FAA AD 2007-12-10].

The original Emergency Airworthiness Directive (AD) 2007-0188-E mandated a repetitive inspection of the APU Generator Scavenge filter element and filter housing and APU Generator Drain plug for signs of small debris coming from the APU Generator and therefore to detect any APU Generator failure in an early stage.
* * * * *

The corrective action includes retaining the requirements of the existing AD (a one-time inspection of the inlet screen and, for certain airplanes, a check of the differential pressure indicator button, and applicable corrective actions). The corrective action adds repetitive inspections of the APU Generator scavenge oil filter element and housing and the APU Generator drain plug for signs of metallic debris, and applicable corrective actions. Those corrective actions include shipping the debris to Airbus or Goodrich. The corrective actions also include the following:

Replacing the APU generator scavenge oil filter for airplanes on which metallic debris is found.

Inspecting the inside filter element and outer diameter of the filter housing for damage to the packing and replacing the packing if damaged.

Cleaning the generator drain plug and reinstalling the plug with a new seal for airplanes on which no metallic debris or metallic debris within acceptable criteria is found.

Keeping the APU inoperative.

You may obtain further information by examining the MCAI in the AD docket.

Relevant Service Information

Airbus has issued All Operators Telexes (AOTs) A330-24A3044 and A340-24A5021, both Revision 01, both dated July 20, 2007; and AOT A340- 24A4057, Revision 02, dated August 14, 2007. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This AD

This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are issuing this AD because we evaluated all pertinent information and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design.

Differences Between the 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 FAA policies. Any such differences are highlighted in a NOTE within the AD.

FAA's Determination of the Effective Date

An unsafe condition exists that requires the immediate adoption of this AD. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because an uncontained APU failure can lead to damage to the APU fire wall, which might reduce its fire extinguishing capability, possibly leading to an uncontrolled fire. Therefore, we determined that notice and opportunity for public comment before issuing this AD are impracticable and that good cause exists for making this amendment effective in fewer than 30 days.

Comments Invited

This AD is a final rule that involves requirements affecting flight safety, and we did not precede it by notice and opportunity for public comment. We invite you to send any written relevant data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include"Docket No. FAA-2007-29073; Directorate Identifier 2007-NM-178- AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because 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 we receive about this AD.

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 (44FR 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.

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 removing Amendment 39-15088 (72 FR 31973, June 11, 2007) and adding the following new AD: