Federal Aviation Administration (FAA), Department of Transportation (DOT).
Supplemental notice of proposed rulemaking; reopening of comment period.
This document revises an earlier proposed airworthiness directive (AD), applicable to all of the airplanes identified above. That proposed AD would have required repetitive inspections to detect breaks in the bottom flange fitting of the ram air turbine (RAT); and corrective actions, if necessary. This new action revises the proposed AD by proposing to remove the requirement to repeat the inspections and, instead, revising the FAA-approved maintenance program to include a new Airplane Maintenance Manual task that specifies a detailed inspection after each RAT extension. This new action also proposes to require, for certain airplanes, an adjustment of the ejection jack; and, for certain other airplanes, replacement of the aluminum part with an improved steel part; these actions would terminate the inspection requirements of the earlier proposed AD. The actions specified by this new proposed AD are intended to prevent failure of the RAT yoke fitting, which could result in the Start Printed Page 26885loss of RAT function and possible loss of critical flight control in the event of certain emergency situations. This action is intended to address the identified unsafe condition.
Comments must be received by June 5, 2006.
Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2003-NM-123-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9 a.m. and 3 p.m., Monday through Friday, except Federal holidays. Comments may be submitted via fax to (425) 227-1232. Comments may also be sent via the Internet using the following address: firstname.lastname@example.org. Comments sent via fax or the Internet must contain “Docket No. 2003-NM-123-AD” in the subject line and need not be submitted in triplicate. Comments sent via the Internet as attached electronic files must be formatted in Microsoft Word 97 or 2000 or ASCII text.
The service information referenced in the proposed rule may be obtained from Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.Start Further Info
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.End Further Info End Preamble Start Supplemental Information
Interested persons are invited to participate in the making of the proposed rule by submitting such written data, views, or arguments as they may desire. Communications shall identify the Rules Docket number and be submitted in triplicate to the address specified above. All communications received on or before the closing date for comments, specified above, will be considered before taking action on the proposed rule. The proposals contained in this action may be changed in light of the comments received.
Submit comments using the following format:
- Organize comments issue-by-issue. For example, discuss a request to change the compliance time and a request to change the service bulletin reference as two separate issues.
- For each issue, state what specific change to the proposed AD is being requested.
- Include justification (e.g., reasons or data) for each request.
Comments are specifically invited on the overall regulatory, economic, environmental, and energy aspects of the proposed rule. All comments submitted will be available, both before and after the closing date for comments, in the Rules Docket for examination by interested persons. A report summarizing each FAA-public contact concerned with the substance of this proposal will be filed in the Rules Docket.
Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this action must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 2003-NM-123-AD.” The postcard will be date stamped and returned to the commenter.
Availability of NPRMs
Any person may obtain a copy of this NPRM by submitting a request to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2003-NM-123-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.
A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to add an airworthiness directive (AD), applicable to Airbus Model A300 B2 and A300 B4; A300 B4-600, A300 B4-600R, A300 C4-605R Variant F, A300 F4-600R (collectively called A300-600); and A310 series airplanes, was published as a notice of proposed rulemaking (NPRM) in the Federal Register on April 1, 2004 (69 FR 17115). That NPRM would have required repetitive inspections to detect breaks in the bottom flange fitting of the ram air turbine (RAT); and corrective actions, if necessary. That NPRM also would have required submission of an inspection report to the airplane manufacturer. That NPRM resulted from a report that the swivel coupling of the ram air turbine (RAT) yoke fitting was found broken on a Model A310 series airplane. That condition, if not corrected, could result in the loss of RAT function and possible loss of critical flight control in the event of certain emergency situations.
Actions Since Issuance of Previous Proposal
The preamble to the NPRM specified that we considered the requirements “interim action” and that the manufacturer was analyzing inspection reports in order to obtain better insight into the nature, cause, and extent of the damage, and eventually to develop a final action to address the unsafe condition. That NPRM explained that we may consider further rulemaking if a final action is developed, approved, and available.
Since the issuance of that NPRM, Airbus has confirmed that the failure of the swivel yoke fitting is due to incorrect rigging of the RAT ejection jack, which leads to overstress of the bottom flange of the coupling yoke fitting. Airbus has developed an improved on-wing rigging procedure for airplanes equipped with certain Sundstrand RATs, which will prevent overload of the swivel coupling yoke fitting. Airbus has determined that, for airplanes equipped with Dowty Rotol RATs, an improved rigging procedure is not possible and, therefore, Airbus has developed a modification for replacing the aluminum part with an improved steel part.
Explanation of Relevant Service Information
Since we issued the original NPRM, Airbus has issued A300-600 All Operators Telex (AOT) 57A6096, Revision 01; and A310 AOT 57A2085, Revision 01; both dated April 11, 2005. (The original issues of these AOTs, both dated March 6, 2003, were referenced as the appropriate source of service information for accomplishing the required actions in the original NPRM. The original issue of French airworthiness directive, 2003-149(B), dated April 16, 2003, was also referenced in the original NPRM.) These AOTs describe procedures for doing a one-time detailed inspection for breaks of the bottom flange fitting of the RAT; replacing it with a new aluminum or steel part, if necessary; and doing an adjustment of the ejection jack. The Direction Générale de l'Aviation Civile (DGAC) classified these AOTs as mandatory.
Airbus has also issued Airbus Service Bulletins A300-57-0244, dated March 4, 2005; A300-57-6099, dated February 23, 2005; and A310-57-2086, dated March 1, 2005. These service bulletins describe procedures for replacing the existing aluminum swivel coupling fork fitting with a new steel part. The procedures in Service Bulletin A300-57-0244 apply to airplanes equipped with Dowty Rotol RATs. The procedures in Airbus Service Bulletins A300-57-6099 and A310-57-2086 apply to airplanes with Dowty Rotol or Sundstrand RATs. Start Printed Page 26886
Airbus has also issued Temporary Revision (TR) 29-015, dated April 12, 2005, to the Airbus A300 Aircraft Maintenance Manual (AMM) Chapter 29-25-00. Airbus has also issued revisions to the following AMM chapters: A300-600 AMM 29-25-00, and A310 AMM 29-25-00; each dated June 1, 2005. The TR and AMM chapters specify an inspection for breaks of the bottom flange of the RAT swivel coupling yoke fitting after each RAT retraction; replacement of the RAT swivel coupling yoke fitting with a new part if necessary; adjustment of the RAT extension jack if necessary; and adjustment of the RAT mechanical control system.
Accomplishing the actions specified in the service information is intended to adequately address the unsafe condition. The DGAC mandated the service information and issued the following French airworthiness directives to ensure the continued airworthiness of these airplanes in France: F-2003-149 R1, dated June 8, 2005 (which changes the repetitive inspection in the AOTs to a one-time inspection); F-2005-089, dated June 8, 2005; and F-2005-090 R1, dated July 6, 2005.
We have given due consideration to the comments received in response to the original NPRM.
Request To Remove Repetitive Inspection Requirement
FedEx states that it has inspected 90 airplanes of its affected fleet and has not found any cases of cracks in the flange fitting for the RAT. FedEx further states that it has incorporated Airbus's advice to prevent overstressing the fitting by performing a check for overfilling of the RAT jack fluid level. FedEx suggests that, based on its own experience with its own airplanes that range from 6,500 flight hours to 53,000 flight hours, the repetitive inspections proposed in paragraphs (b)(1) and (b)(2) of the original NPRM may not be necessary. FedEx does not object to the one-time inspection proposed in paragraph (b) of the original NPRM.
We partially agree. As discussed previously, Airbus has issued TRs to the A300, A300-600, and A310 AMMs to revise the maintenance programs. These TRs include the task of a detailed inspection of the fork fitting at each maintenance of the RAT, which includes an inspection after each RAT extension. This supplemental NPRM (SNPRM) proposes to require incorporating this new AMM task into the operator's FAA-approved maintenance program. We have determined that inspections accomplished at the interval of RAT maintenance actions are more appropriate than the 600 flight-hour interval proposed by the NPRM in paragraphs (b)(1) and (b)(2). We have removed the repetitive inspection requirements from paragraph (a) of the SNPRM (paragraphs (b)(1) and (b)(2) of the NPRM). We have replaced these repetitive inspection requirements with a proposal in paragraph (c) to require revising the FAA-approved maintenance program to include a new AMM task that specifies a detailed inspection after each RAT extension.
Request To Lengthen Repetitive Inspection Intervals
UPS requests that we lengthen the repetitive inspection intervals from intervals not to exceed 600 flight hours, to an interval of every 30 months. UPS states that this interval coincides with the existing mandatory checks of the RAT system.
As noted above, we have removed the repetitive inspection requirements from the SNPRM. Also as stated above, the repetitive inspection requirements of paragraph (b)(1) and (b)(2) of the NPRM have been removed and therefore the SNPRM has been revised relative to the NPRM.
Request To Lengthen Initial Inspection Threshold
The Air Transportation Association and American Airlines request that we extend the compliance time for doing the initial inspection of the yoke fitting. The commenters propose that we extend the compliance time for doing the initial inspection from the earlier of 600 flight hours or 3 months, to 6 months. American Airlines explains that it did the initial inspection on its A300-600 fleet in 2003, but found no cracks during this initial inspection; however, American Airlines notes that it experienced delays in doing the initial inspection because replacement parts for the yoke fitting were not available. American Airlines points out that in order to avoid grounding airplanes, operators will need to establish inventories of yoke fittings at field and main base maintenance stations before they do the initial inspection. The commenters therefore suggest that the extended compliance time for the initial inspection would allow operators to acquire replacement parts. The commenters state that, given the lack of findings in 2003, the extension should not present significant additional risk.
We agree. Since we issued the original NPRM, the DGAC and Airbus have re-assessed the risk based on fleet reports from the original inspections that the DGAC specified through its airworthiness directive F-2003-149(B), dated April 16, 2003, which was cited in the original NPRM. Extending the compliance time will not adversely affect safety. We have revised paragraph (a) of the SNPRM to propose a new compliance time of the earlier of 1,300 flight hours, or 6 months after the effective date of the proposed AD.
Request To Include Adjustment of Ejection Jack Length as Terminating Action for Inspections
UPS proposes that removing the ejection jack from the airplane and returning it to a component shop for verification of proper length and adjustment if necessary, would be sufficient to provide terminating actions for the repetitive inspections. UPS states that preliminary indications show that an overlength ejection jack is at the root of the failed yoke fittings, and that by ensuring proper length, the conditions for yoke fitting failures would be eliminated.
We partially agree. We agree that the root cause of the failed yoke fittings is overstress during the extension of an incorrectly adjusted RAT ejection jack. We disagree that sending the ejection jack to a component shop for verification and adjustment would eliminate the conditions for yoke fitting failures and thus eliminate the need for repetitive inspections. The RAT must be retracted after each extension using the AMM procedure that includes adjusting the ejection jack to ensure that the proper adjustment remains. Sending the jack away for adjustment and verification would not ensure that the correct length would still remain for subsequent RAT extensions. Repetitive inspections would still be specified in accordance with the revised AMM task after each RAT extension.
Explanation of Change to Applicability
We have revised the applicability of this supplemental NPRM to be consistent with the effectivity of the French airworthiness directives listed in Note 5 of this supplemental NPRM.
Clarification of Inspection Terminology
In this proposed AD, the “inspection” specified in the AMM chapters, and the “detailed visual inspection” specified in the AOTs, is referred to as a “detailed inspection.” We have included the definition for a detailed inspection in a note in the proposed AD. Start Printed Page 26887
Clarification of Alternative Method of Compliance (AMOC) Paragraph
We have revised this action to clarify the appropriate procedure for notifying the principal inspector before using any approved AMOC on any airplane to which the AMOC applies.
Explanation of Removed Reporting Requirement
We have removed the inspection report proposed in paragraph (c) of the NPRM. The preamble of the NPRM stated that the manufacturer was analyzing these inspection reports in order to obtain better insight into the nature, cause, and extent of the damage, and eventually to develop a final action to address the unsafe condition. This SNPRM addresses that final action.
Explanation of Change to Cost Impact
After the existing AD was issued, we reviewed the figures we have used over the past several years to calculate AD costs to operators. To account for various inflationary costs in the airline industry, we find it necessary to increase the labor rate used in these calculations from $65 per work hour to $80 per work hour. The cost impact information, below, reflects this increase in the specified hourly labor rate.
Since this change expands the scope of the originally proposed rule, the FAA has determined that it is necessary to reopen the comment period to provide additional opportunity for public comment.
The following table provides the estimated costs for U.S. operators to comply with this proposed AD. There are approximately 165 airplanes of U.S. registry that would be affected by this proposed AD.
|Action||Work hours||Average labor rate per hour||Parts||Cost per airplane|
|Replacement with Steel Fork Fitting||6||80||470||950|
The cost impact figure discussed above is based on assumptions that no operator has yet accomplished any of the proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted. The cost impact figures discussed in AD rulemaking actions represent only the time necessary to perform the specific actions actually required by the AD. These figures typically do not include incidental costs, such as the time required to gain access and close up, planning time, or time necessitated by other administrative actions.
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.
The regulations proposed herein 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. Therefore, it is determined that this proposal would not have federalism implications under Executive Order 13132.
For the reasons discussed above, I certify that this 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) if promulgated, 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 copy of the draft regulatory evaluation prepared for this action is contained in the Rules Docket. A copy of it may be obtained by contacting the Rules Docket at the location provided under the caption ADDRESSES.Start List of Subjects
List of Subjects in 14 CFR Part 39End List of Subjects
The Proposed Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration proposes to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) as follows:Start Part
PART 39—AIRWORTHINESS DIRECTIVES
1. The authority citation for part 39 continues to read as follows:
2. Section 39.13 is amended by adding the following new airworthiness directive:
Airbus: Docket 2003-NM-123-AD.
Applicability: Model A300 airplanes; A300 B4-601, B4-603, B4-620, B4-622, B4-605R, B4-622R, F4-605R, F4-622R, and C4-605R Variant F series airplanes (collectively called A300-600 series airplanes); and A310 airplanes; certificated in any category.
Compliance: Required as indicated, unless accomplished previously.
To prevent failure of the ram air turbine (RAT) yoke fitting, which could result in the loss of RAT function and possible loss of critical flight control in the event of certain emergency situations, accomplish the following:
Detailed Inspections and Replacement
(a) Within 1,300 flight hours or 6 months after the effective date of this AD, whichever occurs first: For all airplanes, do a detailed inspection for breaks of the bottom flange fitting of the yoke fitting for the RAT swivel coupling in accordance with the applicable All Operators Telex (AOT) in paragraph (a)(1), (a)(2), or (a)(3) of this AD. If the flange fitting is broken, before further flight, replace the flange fitting with a new flange fitting in accordance with the applicable AOT. For Model A300 airplanes, A300-600 series airplanes, and A310 airplanes, equipped with Hamilton Sundstrand RATs, verify the adjustment of the ejection jack, and correct the adjustment as applicable. Start Printed Page 26888
(1) For Model A300 airplanes: Airbus A300 AOT 57A0241, dated March 6, 2003.
(2) For Model A300-600 series airplanes: Airbus A300-600 AOT 57A6096, Revision 01, dated April 11, 2005.
(3) For Model A310 airplanes: Airbus A310 AOT 57A2085, Revision 01, dated April 11, 2005.
For the purposes of this AD, a detailed inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”
(b) For Model A300 airplanes, A300-600 series airplanes, and A310 airplanes equipped with Dowty Rotol RATs, except airplanes on which Airbus Modification 12986 has been done: Within 12 months after the effective date of this AD, replace the RAT swivel coupling fork fitting with a new steel fitting, in accordance with the Accomplishment Instructions of Airbus Service Bulletin A300-57-0244, dated March 4, 2005 (for Model A300 series airplanes); A300-57-6099, dated February 23, 2005 (for Model A300-600 airplanes); or A310-57-2086, dated March 1, 2005 (for Model A310 airplanes); as applicable.
(c) Within 3 months after the effective date of this AD: Incorporate the information in the applicable airplane maintenance manual (AMM) specified in paragraphs (c)(1) and (c)(2) of this AD, and the Airbus temporary revision (TR) specified in paragraph (c)(3) of this AD, into the FAA-approved maintenance program to specify an inspection for breaks of the bottom flange of the RAT swivel coupling yoke fitting after each RAT extension; and replacement of the RAT swivel coupling yoke fitting with a new aluminum part as applicable; in accordance with method approved by either the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA; or the Direction Générale de l'Aviation Civile (or its delegated agent). The page blocks specified in paragraphs (c)(1) and (c)(2) of this AD, as applicable, are one approved method for the actions required by paragraph (c) of this AD. Thereafter, except as provided by paragraph (e) of this AD, no alternative inspection intervals may be approved for the bottom flange of the RAT swivel coupling yoke fitting.
(1) Airbus A300-600 AMM, Chapter 29-25-00, Page Block 301, dated June 1, 2005.
(2) Airbus A310 AMM, Chapter 29-25-00, Page Block 301, dated June 1, 2005.
(3) Airbus TR 29-015, dated April 12, 2005, to the Airworthiness Limitations (AWL) section of the Airbus A300 AMM, Chapter 29-25-00.
After revising the maintenance program to include the required periodic inspections according to this paragraph, operators do not need to make a maintenance log entry to show compliance with this AD every time those inspections are accomplished thereafter.
The actions required by paragraph (c)(3) of this AD may be done by inserting a copy of TR 29-015 into the AWL section of the Airbus A300 AMM, Chapter 29-25-00. When this TR has been included in general revisions of the AMM, the general revisions may be inserted in the AMM, provided the relevant information in the general revision is identical to that in TR 29-015.
This AD requires revisions to certain operator maintenance documents to include new inspections. Compliance with these inspections is required by 14 CFR 91.403(c). For airplanes that have been previously modified, altered, or repaired in the areas addressed by these inspections, the operator may not be able to accomplish the inspections described in the revisions. In this situation, to comply with 14 CFR 91.403(c), the operator must request approval for an alternative method of compliance according to paragraph (e) of this AD. The request should include a description of changes to the required inspections that will ensure the continued damage tolerance of the affected structure. The FAA has provided guidance for this determination in Advisory Circular (AC) 25-1529.
Credit for Actions Accomplished Previously
(d) Actions done before the effective date of this AD in accordance with Airbus AOT 57A6096, dated March 6, 2003; or Airbus AOT 57A2085, dated March 6, 2003; are acceptable for compliance with the corresponding action in paragraph (a) of this AD.
Alternative Methods of Compliance
(e)(1) In accordance with 14 CFR 39.19, the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, is authorized to approve alternative methods of compliance for this AD.
(2) Before using any AMOC approved in accordance with § 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.
The subject of this AD is addressed in French airworthiness directives F-2005-089, dated June 8, 2005; F-2005-090 R1, dated July 6, 2005; and F-2003-149 R1, dated June 8, 2005.
Issued in Renton, Washington, on April 28, 2006.
Manager, Transport Airplane Directorate, Aircraft Certification Service.
[FR Doc. E6-7003 Filed 5-8-06; 8:45 am]
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