05-6758. 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 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 certain Airbus Model A300-600 airplanes. This proposed AD would require an inspection for evidence of chafing between the hydraulic flexible hose and the ram air turbine (RAT) hub, and related investigative and corrective actions if necessary. This proposed AD is prompted by reports of holes in the RAT hub cover. We are proposing this AD to prevent a hole in the RAT hub cover. A hole in the RAT hub cover could allow water to enter the RAT governing mechanism, freeze during flight, and jam the governing mechanism. In addition, the metal particles that result from chafing between the hydraulic flexible hose and the RAT could mix with the lubricant grease and degrade the governing mechanism. In an emergency, a jammed or degraded RAT could result in its failure to deploy, loss of hydraulic pressure or electrical power to the airplane, and consequent reduced controllability of the airplane.

DATES:

We must receive comments on this proposed AD by May 6, 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].
• 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. This docket number is FAA-2005-20867; the directorate identifier for this docket is 2004-NM-188-AD.

FOR FURTHER INFORMATION CONTACT:

Dan Rodina, 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-2005-20867; Directorate Identifier 2004-NM-188-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 us that an unsafe condition may exist on certain Airbus Model A300 B4-600, B4-600R, and F4-600R series airplanes, and Model C4-605R Variant F airplanes (collectively called A300-600 airplanes). The DGAC advises that, during a maintenance inspection, an operator discovered a hole in the ram air turbine (RAT) hub. Investigation revealed that the hole resulted from chafing between the hydraulic flexible hose and RAT hub cover. Further investigation revealed that a similar finding had been reported during airplane production. The subsequent investigation revealed that, when the flexible hoses for the hydraulic system were installed, the binding had not been performed correctly. Due to the incorrect installation of the binding, a hose chafed the RAT hub and eventually wore a hole into the hub cover. A hole in the RAT hub cover could allow water to enter the RAT governing mechanism, freeze during flight, and jam the governing mechanism. In addition, the metal particles that result from chafing between the hydraulic flexible hose and the RAT could mix with the lubricant grease and degrade the governing mechanism. In an emergency, a jammed or degraded RAT could result in failure of RAT deployment, loss of hydraulic pressure or electrical power to the airplane, and consequent reduced controllability of the airplane.

Relevant Service Information

Airbus has issued Service Bulletin A300-29-6054, Revision 01, including Appendix 01, dated November 4, 2004. The service bulletin describes procedures for doing a one-time detailed visual inspection for evidence of chafing between the hydraulic flexible hose and the RAT hub, and related investigative and corrective actions. The related investigative and corrective actions include:

• If any damage is found on the RAT hub, referencing the Airbus A300-600 Component Maintenance Manual (CMM) to determine if the damage is within the limits specified in the CMM.
• Replacing the RAT if any damage exceeds the limits specified in the CMM.
• Replacing a damaged hose.
• If no damage is found on the RAT hub, measuring the clearance between the hydraulic flexible hose and the RAT hub.
• If the clearance between the hydraulic flexible hose and the RAT hub is insufficient, and the hose is not damaged, reworking the binding of the hose.

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 F-2004-133, dated August 4, 2004, to ensure the continued airworthiness of these airplanes in France.

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 under “Difference Among the Proposed AD, French Airworthiness Directive, and Service Bulletin.”

Difference Among the Proposed AD, French Airworthiness Directive, and Service Bulletin

Operators should note that, although the parallel French airworthiness directive and service bulletin include a requirement to submit inspection results to the airplane manufacturer, this proposed AD would not require that action. Furthermore, where the service bulletin specifies to return damaged RATs to the vendor or a repair station, this proposed AD would not require that action.

Clarification of Inspection Terminology

In this proposed AD, the “detailed visual inspection” specified in the Airbus service bulletin is referred to as a “detailed inspection.” We have included the definition for a detailed inspection in a note in this proposed AD.

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. -registered airplanes	Fleet cost
Inspection	1	$65	None required	$65	12	$780
Rework binding	1	65	None required	65	12	780

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-2005-20867; Directorate Identifier 2004-NM-188-AD.

Comments Due Date

(a) The Federal Aviation Administration must receive comments on this AD action by May 6, 2005.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Airbus Model A300 B4-600, B4-600R, and F4-600R series airplanes, and Model C4-605R Variant F airplanes (collectively called A300-600 airplanes); certificated in any category; having serial numbers 0812, 0813, 0815 through 0818 inclusive, 0821 through 0828 inclusive, and 0836 through 0838 inclusive.

Unsafe Condition

(d) This AD was prompted by reports of holes in the ram air turbine (RAT) hub. We are issuing this AD to prevent a hole in the RAT hub cover. A hole in the RAT hub cover could allow water to enter the RAT governing mechanism, freeze during flight, and jam the governing mechanism. In addition, the metal particles that result from chafing between the hydraulic flexible hose and the RAT could mix with the lubricant grease and degrade the governing mechanism. In an emergency, a jammed or degraded RAT could result in failure of RAT deployment, loss of hydraulic pressure or electrical power to the airplane, and consequent 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.

Inspection and Related Investigative/Corrective Actions

(f) Within 2,500 flight hours after the effective date of this AD: Do a one-time detailed inspection for evidence of chafing between the hydraulic flexible hose and the RAT hub, and any applicable related investigative and corrective actions, by accomplishing all of the applicable actions specified in the Accomplishment Instructions of Airbus Service Bulletin A300-29-6054, Revision 01, excluding Appendix 01, dated November 4, 2004. Any applicable corrective actions must be accomplished before further flight. Although the service bulletin specifies to submit certain information to the manufacturer, and to submit damaged RAMs to the vendor or a repair station, this AD does not include those requirements.

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.”

Actions Accomplished Previously

(g) Actions accomplished before the effective date of this AD, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A300-29-6054, excluding Appendix 01, dated June 8, 2004, are acceptable for compliance with the corresponding actions specified in 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 F-2004-133, dated August 4, 2004, also addresses the subject of this AD.

Issued in Renton, Washington, on March 25, 2005.

Ali Bahrami,

Manager, Transport Airplane Directorate, Aircraft Certification Service.