05-20063. Airworthiness Directives; Airbus Model A300 B4-600, B4-600R, and F4-600R Series Airplanes, and Model C4-605R Variant F Airplanes (Collectively Called A300-600 Series Airplanes); and Airbus Model A310-200 and -300 Series Airplanes

AGENCY:

Federal Aviation Administration (FAA), Department of Transportation (DOT).

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

The FAA proposes to adopt a new airworthiness directive (AD) for all Airbus Model A300 B4-600, B4-600R, and F4-600R series airplanes, and Model C4-605R Variant F airplanes (collectively called A300-600 series airplanes); and A310-200 and -300 series airplanes. This proposed AD would require a one-time inspection of the trimmable horizontal stabilizer actuator (THSA), corrective actions if necessary, and follow-on repetitive tasks. This proposed AD is prompted by reports of THSAs that have reached their design operational life. This operational life can be extended provided an initial inspection and follow-on repetitive tasks are accomplished. We are proposing this AD to extend the operational life of the THSA to prevent a possible failure of high-time units, which could result in reduced controllability of the airplane.

DATES:

We must receive comments on this proposed AD by November 7, 2005.

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 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.
• By fax: [phone].
• 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 in person 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 [phone]; fax [phone].

SUPPLEMENTARY INFORMATION:

Comments Invited

We invite you to submit any relevant written data, views, or arguments regarding this proposed AD. Send your comments to an address listed under ADDRESSES. Include “Docket No. FAA-2005-22630; Directorate Identifier 2001-NM-323-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 submitted 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.

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 [phone]) 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

The Direction Générale de l'Aviation Civile (DGAC), which is the airworthiness authority for France, notified the FAA that an unsafe condition may exist on all Airbus Model A300 B4-600, B4-600R, and F4-600R series airplanes, and Model C4-605R Variant F airplanes (collectively called A300-600 series airplanes); and Airbus Model A310-200 and -300 series airplanes. The trimmable horizontal stabilizer actuator (THSA) on those airplanes was designed for an operational life of 47,000 total flight hours. The DGAC advises that some THSAs installed on those airplanes have reached this operational limit. The DGAC has mandated an inspection and maintenance program to maintain the THSA's design reliability objective beyond its original 47,000-total-flight-hour operational life. The inspection and scheduled maintenance program of certain THSA components will allow an increase of the THSA's operational life limit, from 47,000 total flight hours to 65,000 total flight hours/40,000 total flight cycles. Failure of the THSA, if not corrected, could result in reduced controllability of the airplane.

Relevant Service Information

Airbus has issued Service Bulletins A300-27-6044, Revision 04, dated September 10, 2001 (for Model A300-600 series airplanes); and A310-27-2089, Revision 02, dated June 28, 2001 (for Model A310-200 and -300 series airplanes). These service bulletins describe procedures for inspecting the THSA, and performing corrective actions and follow-on repetitive tasks as necessary. The procedures involve:

• A detailed inspection of the THSA screw shaft thread surface for chrome plate wear and corrosion, and replacement of a worn or corroded unit with a new or serviceable (refurbished) unit.
• A detailed inspection of the THSA lower claw stop for debonding between the rubber and the inner/outer ring; measurement of the relative displacement of the inner and outer claw stop rings; and replacement, with a new stop, of any stop that has exceeded specified limits.
• A detailed inspection of the THSA fail-safe tie bar for corrosion, and replacement of any corroded fail-safe tie bar with a new or serviceable (refurbished) unit.

The repetitive tasks include:

Repetitive Actions

Action	Repetitive interval (flight hours)
Checking for external oil leakage	1,200
Lubricating the ball screw nut	600
Checking the magnetic chip detector	2,400
Inspecting the upper and lower attachments and ball screw	2,000
Checking certain oil pumps and static torque	7,000

After a THSA is replaced with a new or serviceable THSA, there is no need to do the repetitive tasks until 47,000 flight hours after the replacement.

Accomplishment of the actions specified in the Airbus service bulletins is intended to adequately address the identified unsafe condition. The DGAC classified these service bulletins as mandatory and issued French airworthiness directive 2001-242(B), dated June 27, 2001, to ensure the continued airworthiness of these airplanes in France.

The Airbus service bulletins refer to “Lucas Service Bulletin 47142-27-11” as an additional source of service information for the inspections. This document is actually identified as Goodrich Actuation Systems Service Bulletin 47142-27-11 (currently at Revision 3, dated April 25, 2005).

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 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 we need to issue an AD for products of this type design that are certificated for operation in the United States.

Therefore, we are proposing this AD, which would require accomplishing the actions specified in the service information described previously, except as discussed below.

Difference Between Proposed AD and Service Bulletin

The service bulletin specifies that you may contact the manufacturer for instructions on how to repair certain conditions, but this proposed AD would require you to repair those conditions using a method that we or the DGAC (or its delegated agent) approve. In light of the type of repair that would be required to address the unsafe condition, and consistent with existing bilateral airworthiness agreements, we have determined that, for this proposed AD, a repair we or the DGAC approve would be acceptable for compliance with this proposed AD.

Clarification of Inspection Type

The service bulletins do not specify the type of inspection that would be required by this proposed AD. We have determined that this inspection is a detailed inspection. Note 1 of this proposed AD defines a detailed inspection.

Costs of Compliance

The following table provides the estimated costs for U.S. operators to comply with this proposed AD.

Estimated Costs

Action	Work hours	Average labor rate per hour	Parts	Cost per airplane	Number of U.S.-reg. airplanes	Fleet cost
Inspection	3	$65	None required	$195	146	$28,470.
Repetitive follow-on tasks	12	65	$0	$780, per inspection cycle	146	$113,880, per inspection cycle.

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 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

[Amended]

2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):

Airbus: Docket No. FAA-2005-22630; Directorate Identifier 2001-NM-323-AD.

Comments Due Date

(a) The Federal Aviation Administration must receive comments on this AD action by November 7, 2005.

Affected ADs

(b) None.

Applicability

(c) This AD applies to all of the following Airbus airplanes, certificated in any category:

Model A300 B4-601, B4-603, B4-620, and B4-622 airplanes

Model A300 B4-605R and B4-622R airplanes

Model A300 F4-605R and F4-622R airplanes

Model A300 C4-605R Variant F airplanes

Model A310-203, -204, -221, and -222 airplanes

Model A310-304, -322, -324, and -325 airplanes

Unsafe Condition

(d) This AD was prompted by reports of trimmable horizontal stabilizer actuators (THSAs) that have reached their design operational life. We are issuing this AD to extend the operational life of the THSA to prevent a possible failure of high-time units, which could result in reduced controllability of the airplane.

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.

Service Bulletin References

(f) Unless otherwise specified in this AD, the term “service bulletin,” as used in this AD, means the Accomplishment Instructions of the applicable service bulletin identified in Table 1 of this AD. The service bulletins refer to Goodrich Actuation Systems Service Bulletin 47142-27-11, Revision 3, dated April 25, 2005, as an additional source of service information for the required actions.

Table 1.—Service Bulletins

For Airbus Model—	Use Airbus Service Bulletin—	Actions done before the effective date of this AD are also acceptable if done in accordance with Airbus Service Bulletin—
A300 B4-601, B4-603, B4-620, and B4-622 airplanes; A300 B4-605R and B4-622R airplanes; A300 F4-605R and F4-622R airplanes; and A300 C4-605R Variant F airplanes	A300-27-6044, Revision 04, dated September 10, 2001	A300-27-6044, Revision 02, dated August 26, 2000; or Revision 03, dated June 28, 2001.
A310-203, -204, -221, and -222 airplanes; and A310-304, -322, -324, and -325 airplanes	A310-27-2089, Revision 02, dated June 28, 2001	A310-27-2089, Revision 01, dated August 8, 2000.

Inspection

(g) At the applicable time specified in paragraph (g)(1) or (g)(2) of this AD, do a detailed inspection of specified components of the THSA in accordance with paragraph E.(2)(a) of the applicable service bulletin. Repair any discrepancy before further flight in accordance with a method approved by the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA; or the Direction Générale de l'Aviation Civile (DGAC) (or its delegated agent).

(1) If the flight hours accumulated on the THSA can be positively determined: Inspect before the accumulation of 47,000 total flight hours on the THSA, or within 600 flight hours after the effective date of this AD, whichever occurs later.

(2) If the flight hours accumulated on the THSA cannot be positive determined: Inspect before the accumulation of 47,000 total flight hours on the airplane, or within 600 flight hours after the effective date of this AD, whichever occurs later.

Note 1:

For the purposes of this AD, a detailed inspection is: “An intensive examination of a specific item, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at an intensity deemed appropriate. Inspection aids such as mirror, magnifying lenses, etc., may be necessary. Surface cleaning and elaborate procedures may be required.”

Follow-on Repetitive Tasks

(h) After the inspection required by paragraph (g) of this AD: Do the repetitive tasks in accordance with and at the times specified in paragraph E.(2)(b) of the service bulletin, as applicable, except as provided by paragraph (i) of this AD. The repetitive tasks are valid only until the THSA operational life exceeds the first occurring of 65,000 flight hours or 40,000 flight cycles. Before operating the THSA beyond these extended life goals, the operator must replace the THSA with a new THSA, except as provided by paragraph (i) of this AD.

THSA Replacement

(i) For any THSA, whether discrepant or not, that is replaced with a new THSA: Within 47,000 flight hours after the THSA is replaced, do the applicable tasks specified in paragraph E.(2)(a) of the applicable service bulletin. Thereafter repeat the tasks within the repetitive intervals specified in paragraph E.(2)(b) of the applicable service bulletin.

Alternative Methods of Compliance (AMOCs)

(j)(1) The Manager, International Branch, ANM-116, has the authority to approve AMOCs for this AD, if requested in accordance with the procedures found in 14 CFR 39.19.

(j)(2) Before using any AMOC approved in accordance with 14 CFR 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

Related Information

(k) French airworthiness directive 2001-242(B), dated June 27, 2001, also addresses the subject of this AD.

Issued in Renton, Washington, on September 28, 2005.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.