Document Headings

                    Document headings vary by document type but may contain                    the following:                  
                -                       the agency or agencies that issued and signed a document                    
                -                       the number of the CFR title and the number of each part                      the document amends, proposes to amend, or is directly                      related to                    
                -                       the agency docket number / agency internal file number                    
                -                       the RIN which identifies each regulatory action listed in                      the Unified Agenda of Federal Regulatory and Deregulatory                      Actions                    

                    See the                                          Document Drafting Handbook                                        for more details.                  

###### Department of Transportation

###### Federal Aviation Administration 

          - 14 CFR Part 39 
          - [Docket No. FAA-2004-19227; Directorate Identifier 2003-NM-95-AD] 
          - RIN 2120-AA64 

# AGENCY:

Federal Aviation Administration (FAA), DOT. 

# ACTION:

Notice of proposed rulemaking (NPRM). 

# SUMMARY:

The FAA proposes to supersede an existing airworthiness directive (AD) that applies to certain Airbus Model A300 B2 and B4 series airplanes; Model A300 B4-600, A300 B4-600R, C4-605R Variant F, and A300 F4-600R (collectively called A300-600) series airplanes; and Model A310 series airplanes. The existing AD currently requires replacement of the transformer rectifier units (TRUs) in the avionics compartment with new, improved TRUs. This proposed AD would require replacement of the TRUs installed according to the existing AD with different TRUs that are improved. This proposed AD is prompted by analysis that has revealed that certain diodes installed in the TRUs are the main factor contributing to the continuing TRU failures. We are proposing this AD to prevent failure of the TRUs. Failure of multiple TRUs could result in loss of the thrust reversers, autothrottle, flaps, and various systems (wing/cockpit window anti-ice, trim tank pumps, and windshield wipers) on the airplane; or display of incorrect information to the flightcrew. 

# DATES:

We must receive comments on this proposed AD by November 3, 2004. 

# ADDRESSES:

Use one of the following addresses to submit comments on this proposed AD. 
      - DOT Docket Web site: Go to http://dms.dot.gov                          and follow the instructions                                ( print page 59154)                              for sending your comments electronically.                     
      - Government-wide rulemaking Web site: Go to http://www.regulations.gov                          and follow the instructions for sending your comments electronically.                     
      - Mail: Docket Management Facility; U.S. Department of Transportation, 400 Seventh Street SW., Nassif Building, room PL-401, Washington, DC 20590.
      - Fax: (202) 493-2251.
      - Hand Delivery: Room PL-401 on the plaza level of the Nassif Building, 400 Seventh Street SW., Washington, DC, between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays.

For service information identified in this proposed AD, contact Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. 

                        You can examine the contents of this AD docket on the Internet at                         *http://dms.dot.gov,*                         or at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street SW., room PL-401, on the plaza level of the Nassif Building, Washington, DC.                     

# FOR FURTHER INFORMATION CONTACT:

Tim Backman, Aerospace Engineer, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2797; fax (425) 227-1149. 

# SUPPLEMENTARY INFORMATION:

## Docket Management System (DMS) 

The FAA has implemented new procedures for maintaining AD dockets electronically. As of May 17, 2004, new AD actions are posted on DMS and assigned a docket number. We track each action and assign a corresponding directorate identifier. The DMS AD docket number is in the form “Docket No. FAA-2004-99999.” The Transport Airplane Directorate identifier is in the form “Directorate Identifier 2004-NM-999-AD.” Each DMS AD docket also lists the directorate identifier (“Old Docket Number”) as a cross-reference for searching purposes. 

## Comments Invited 

                    We invite you to submit any written relevant data, views, or arguments regarding this proposed AD. Send your comments to an address listed under                     **ADDRESSES.**                     Include “Docket No. FAA-2004-19227; Directorate Identifier 2003-NM-95-AD” at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of the proposed AD. We will consider all comments received by the closing date and may amend the proposed AD in light 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 with FAA personnel concerning this proposed AD. Using the search function of our docket web site, anyone can find and read the comments in any of our dockets, including the name of the individual who sent the comment (or signed the comment on behalf of an association, business, labor union, etc.). You can review the DOT's complete Privacy Act Statement in the                     **Federal Register**                     published on April 11, 2000 (65 FR 19477-78), or you can visit                     *http://dms.dot.gov.*

                    We are reviewing the writing style we currently use in regulatory documents. We are interested in your comments on whether the style of this document is clear, and your suggestions to improve the clarity of our communications that affect you. You can get more information about plain language at                     *http://www.faa.gov/​language*                     and                     *http://www.plainlanguage.gov.*

## Examining the Docket 

                    You can examine the AD docket on the Internet at                     *http://dms.dot.gov,*                     or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the DOT street address stated in the                     **ADDRESSES**                     section. Comments will be available in the AD docket shortly after the DMS receives them.                 

## Discussion 

On August 31, 2000, we issued AD 2000-18-07, amendment 39-11892 (65 FR 54407, September 8, 2000), for certain Airbus Model A300, A300-600, and A310 series airplanes. That AD requires replacement of the transformer rectifier units (TRUs) in the avionics compartment with new, improved TRUs (having part number (P/N) F11QY3121). That AD was prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. We issued that AD to prevent failure of the TRUs. Failure of multiple TRUs could result in loss of the thrust reversers, autothrottle, flaps, and various systems (wing/cockpit window anti-ice, trim tank pumps, and windshield wipers) on the airplane; or incorrect information being displayed to the flightcrew. 

## Actions Since Existing AD Was Issued 

Since we issued AD 2000-18-07, the Direction Générale de l'Aviation Civile (DGAC), which is the airworthiness authority for France, has informed the FAA that failures have continued to occur on the TRUs having P/N F11QY3121, which were installed according to French airworthiness directive 1999-435-296(B), dated November 3, 1999. (French airworthiness directive 1999-435-296(B) is the parallel French airworthiness directive to AD 2000-18-07.) Analysis of these failures by the airplane manufacturer has revealed that certain diodes installed in the TRUs having P/N F11QY3121 are the main factor contributing to the continuing TRU failures. 

## Relevant Service Information 

Airbus has issued Service Bulletins A300-24-0099, A300-24-6082, and A310-24-2088, all Revision 01, all dated December 18, 2003. These service bulletins describe procedures for replacing existing TRUs, having P/N F11QY3121, with new, improved TRUs, having P/N F11QY3714. Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition. The DGAC mandated the service information and issued French airworthiness directive 2003-082R1, dated March 31, 2004, to ensure the continued airworthiness of these airplanes in France. 

The Airbus service bulletins refer to Thales Service Bulletin F11QY3121-24-003, dated October 15, 2002, as an additional source of service information for modifying the existing TRUs to the improved configuration. Thales Service Bulletin F11QY3121-24-003 specifies that Thales Service Bulletins F11QY3121-24-001, dated February 2, 1998; and F11QY3121-24-002, dated October 5, 2000; must be done prior to or concurrent with Thales Service Bulletin F11QY3121-24-003. Those service bulletins modify TRUs having P/N F11QY3121 to include Amendments A and B, respectively. Thales Service Bulletin F11QY3121-24-003 modifies TRU P/Ns F11QY3121 with Amendments A and B, to P/N F11QY3714 (which is the P/N for the improved parts that the Airbus service bulletins recommend installing). 

## FAA's Determination and Requirements of the Proposed AD 

                    These airplane models are manufactured in France and are type certificated for operation in the United States under the provisions of section                           ( print page 59155)                        21.29 of the Federal Aviation Regulations (14 CFR 21.29) and the applicable bilateral airworthiness agreement. Pursuant to this bilateral airworthiness agreement, the DGAC has kept the FAA informed of the situation described above. We have examined the DGAC's findings, evaluated all pertinent information, and determined that AD action is necessary for airplanes of this type design that are certificated for operation in the United States.                 

Therefore, we are proposing this AD, which would supersede AD 2000-18-07 to require replacing existing TRUs with new, improved TRUs. The proposed AD would require you to use the Airbus service information described previously to perform these actions. 

## Difference Between the French Airworthiness Directive and This Proposed AD 

The applicability of French airworthiness directive 2003-082R1 excludes airplanes on which Airbus Service Bulletin A300-24-0099 (for Model A300 B2 and B4 series airplanes), A300-24-6082 (for Model A300-600 series airplanes), or A310-24-2088 (for Model A310 series airplanes), has been accomplished in service. However, we have not excluded those airplanes from the applicability of this proposed AD. Rather, this proposed AD would include a requirement to accomplish the actions specified in those service bulletins. Such a requirement ensures that the actions specified in the service bulletins and that would be required by this proposed AD are accomplished on all affected airplanes. Operators must continue to operate the airplane in the configuration that would be required by this proposed AD unless an alternative method of compliance is approved. 

## Clarification of Inspections Referenced in Thales Service Bulletin 

The Accomplishment Instructions of Thales Service Bulletin F11QY3121-24-003 specify to “complete implementation of the [Service Information Letter] SIL F11QY3121-24-004.” We reviewed that Thales Service Information Letter (SIL), which contains recommendations about TRU overhaul. We have coordinated this issue with Airbus, and they have clarified that it was not their intent to require the recommendations in the SIL. Therefore, this proposed AD does not require doing the SIL. 

## Explanation of Change to Applicability 

We have revised the applicability of the existing AD to identify model designations as published in the most recent type certificate data sheet for the affected models. 

## Costs of Compliance 

This proposed AD would affect about 165 airplanes of U.S. registry. 

The new proposed actions would take about 2 work hours per airplane, at an average labor rate of $65 per work hour. The parts manufacturer would provide required parts free of charge. Based on these figures, the estimated cost of the new actions specified in this proposed AD for U.S. operators is $21,450, or $130 per airplane. 

## Regulatory Findings 

We have determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 that the proposed regulation: 

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 proposed AD. See the                     **ADDRESSES**                     section for a location to examine the regulatory evaluation.                 

# List of Subjects in 14 CFR Part 39

      - Air transportation
      - Aircraft
      - Aviation safety
      - Safety

## The Proposed Amendment 

Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 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 

2. The FAA amends § 39.13 by removing 39-11892 (65 FR 54407, September 8, 2000) and adding the following new airworthiness directive (AD):

**Airbus:**                                 Docket No. FAA-2004-19227; Directorate Identifier 2003-NM-95-AD.                             

## Comments Due Date 

(a) The Federal Aviation Administration must receive comments on this AD action by November 3, 2004. 

## Affected ADs 

(b) This AD supersedes AD 2000-18-07, amendment 39-11892. 

## Applicability 

(c) This AD applies to Model A300 B2 and B4 series airplanes; Model A300 B4-600, A300 B4-600R, C4-605R Variant F, and A300 F4-600R (collectively called A300-600) series airplanes; and Model A310 series airplanes; certificated in any category; except those on which Airbus Modification 12540 has been accomplished. 

## Unsafe Condition 

(d) This AD was prompted by analysis that has revealed that certain diodes installed in the transformer rectifier units (TRUs) are the main factor contributing to the continuing TRU failures. We are issuing this AD to prevent failure of multiple TRUs, which could result in loss of the thrust reversers, autothrottle, flaps, and various systems (wing/cockpit window anti-ice, trim tank pumps, and windshield wipers) on the airplane; or display of incorrect information to the flightcrew. 

## Compliance 

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done. 

## Replacement of TRUs 

(f) Within 36 months after the effective date of this AD, replace the existing TRUs, having P/N F11QY3121, in the avionics compartment with new, improved TRUs having P/N F11QY3714, according to the Accomplishment Instructions of Airbus Service Bulletin A300-27-0099 (for Model A300 B2 and B4 series airplanes), A300-24-6082 (for Model A300-600 series airplanes), or A310-24-2088 (for Model A310 series airplanes); all Revision 01; all dated December 18, 2003; as applicable. 

# Note 1:

Airbus Service Bulletin A300-27-0099, A300-24-6082, or A310-24-2088; all Revision 01; refer to Thales Service Bulletin F11QY3121-24-003, dated October 15, 2002, as an additional source of service information for modifying the existing TRUs to the improved configuration. Thales Service Bulletin F11QY3121-24-003 specifies that Thales Service Bulletins F11QY3121-24-001, dated February 2, 1998; and F11QY3121-24-002, dated October 5, 2000; must be done to add Amendments A and B, respectively, to P/N F11QY3121 before the TRU can be modified to P/N F11QY3714 according to Thales Service Bulletin F11QY3121-24-003. 

# Note 2:

The Accomplishment Instructions of Thales Service Bulletin F11QY3121-24-003 specify to “complete implementation of the [Service Information Letter] SIL F11QY3121-24-004.” This AD does not require doing the Service Information Letter. 
      ( print page 59156)    

## Actions Accomplished Previously 

(g) Replacements done before the effective date of this AD according to Airbus Service Bulletin A300-27-0099 (for Model A300 B2 and B4 series airplanes), A300-24-6082 (for Model A300-600 series airplanes), or A310-24-2088 (for Model A310 series airplanes); dated October 11, 2002; as applicable; are acceptable for compliance with the corresponding action required by paragraph (a) of this AD. 

## Alternative Methods of Compliance (AMOCs) 

(h) The Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19. 

## Related Information 

(i) French airworthiness directive 2003-082R1, dated March 31, 2004, also addresses the subject of this AD.

Issued in Renton, Washington, on September 27, 2004. 

Kalene C. Yanamura, 

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. 

[FR Doc. 04-22267 Filed 10-1-04; 8:45 am] 

BILLING CODE 4910-13-P