Airworthiness Directives; Airbus Model A319, A320, and A321 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Airbus Model A319, A320, and A321 series airplanes, that currently requires revising the FAA-approved Airplane Flight Manual (AFM) to increase monitoring of the flight path of the airplane to detect certain software anomalies of the flight management guidance system, and take appropriate corrective actions. This proposed AD would add a requirement to either modify the existing on-board replaceable modules of the flight management guidance computers (FMGC) to incorporate software changes, or replace the FMGC's with new, improved FMGC's; which would terminate the requirements for the AFM revision. This proposal is prompted by the issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by the proposed AD are intended to prevent erroneous navigational calculations, which could result in an increased risk of collision with terrain or other airplanes.

DATES:

Comments must be received by May 15, 2000.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 99-NM-351-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.

The service information referenced in the proposed rule may be obtained from Airbus Industrie, 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; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC.

FOR FURTHER INFORMATION CONTACT:

Norman B. Martenson, Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington 98055-4056; telephone (425) 227-2110; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

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 notice may be changed in light of the comments received.

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 notice must submit a self-addressed, stamped postcard on which the following statement is made: “Comments to Docket Number 99-NM-351-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. 99-NM-351-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

On October 9, 1997, the FAA issued AD 97-21-10, amendment 39-10163 (62 FR 53939, October 17, 1997), applicable to certain Airbus Model A319, A320, and A321 series airplanes, to require revising the FAA-approved Airplane Flight Manual to increase monitoring of the flight path of the airplane to detect certain software anomalies of the flight management guidance system (FMGS), and take appropriate corrective actions. That action was prompted by the issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The requirements of that AD are intended to ensure that the flightcrew detects and corrects an unintended flight path if certain software anomalies of the FMGS occur, which could result in an increased risk of collision with terrain or other airplanes.

Actions Since Issuance of Previous Rule

In the preamble to AD 97-21-10, the FAA specified that the actions required by that AD were considered “interim action” until final action was identified, at which time further rulemaking action would be considered. Since the issuance of that AD, the Direction Générale de l'Aviation Civile (DGAC), which is the airworthiness authority for France, advises that a new standard of the flight management guidance computer (FMGC) includes software changes that improve navigational guidance calculations. The FAA now has determined that further rulemaking action is indeed necessary to require either the modification of all existing on-board replaceable modules of the FMGC's to incorporate software changes, or replacement of all existing FMGC's with new, improved FMGC's, in order to address the unsafe condition and ensure the continued safe operation of those airplanes. This proposed AD follows from that determination and allows opportunity for public comment.

Explanation of Relevant Service Information

Airbus has issued the following service bulletins:

• A320-22-1063, Revision 01, dated October 8, 1999.
• A320-22-1064, dated September 15, 1998.
• A320-22-1065, dated October 28, 1998.
• A320-22-1067, Revision 01, dated July 7, 1999.
• A320-22-1068, dated December 9, 1998.
• A320-22-1069, dated February 1, 1999.

These service bulletins describe procedures for either the modification of all existing on-board replaceable modules of the FMGC's to incorporate software changes, or the replacement of all existing FMGC's with new, improved FMGC's. The DGAC classified these service bulletins as mandatory and issued French airworthiness directive 1999-411-140(B), dated October 20, 1999, in order to assure the continued airworthiness of these airplanes in France.

FAA's Conclusions

These airplane models are manufactured in France and are type certificated for operation in the United States under the provisions of § 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. The FAA has examined the findings of the DGAC, reviewed all available information, and determined that AD action is necessary for products of this type design that are certificated for operation in the United States.

Explanation of Requirements of Proposed Rule

Since an unsafe condition has been identified that is likely to exist or develop on other airplanes of the same type design registered in the United States, the proposed AD would supersede AD 97-21-10 to continue to require a revision to the Airplane Flight Manual (AFM) to increase monitoring of the flight path of the airplane to detect certain software anomalies of the flight management guidance system, and take appropriate corrective actions. This proposed AD would add a requirement to either modify all existing on-board replaceable modules of the FMGC's to incorporate software changes, or replace all existing FMGC's with new, improved FMGC's; which would terminate the requirements for the AFM revision. The actions would be required to be accomplished in accordance with the service bulletins described previously, as applicable.

This proposed AD also would limit the applicability of the existing AD to airplanes on which a certain modification has been installed or service bulletin has been accomplished, and excludes airplanes on which another modification has been installed or service bulletin has been accomplished.

Other Relevant Rulemaking

The FAA previously has issued AD 98-19-08, amendment 39-10750 (63 FR 50503, September 22, 1998), applicable to certain Airbus Model A321 series airplanes. AD 98-19-08 requires revising the AFM to prohibit automatic landings and Category III operations on runways with a magnetic orientation of 170 degrees through 190 degrees inclusive. That amendment provides optional terminating action for the AFM revision.

The modification or replacement action that would be required by this proposed AD constitutes terminating action for the AFM requirements of AD 98-19-08.

Cost Impact

There are approximately 200 Airbus Model A319, A320, and A321 series airplanes of U.S. registry that would be affected by this proposed AD.

The actions that are currently required by AD 97-21-10 and retained in this AD take approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Required parts would be provided by the manufacturer at no charge to the operators. Based on these figures, the cost impact of the currently required actions on U.S. operators is estimated to be $60 per airplane.

The new actions that are proposed in this AD action would take approximately 1 work hour per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the proposed requirements of this AD on U.S. operators is estimated to be $12,000, or $60 per airplane.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the current or proposed requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact

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.

List of Subjects in 14 CFR Part 39

• Air transportation
• Aircraft
• Aviation safety
• Safety

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:

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.