Airworthiness Directives; Dornier Model 328-100 and -300 Series Airplanes

AGENCY:

Federal Aviation Administration, DOT.

ACTION:

Notice of proposed rulemaking (NPRM).

SUMMARY:

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to all Dornier Model 328-100 and -300 series airplanes. This proposal would require repetitive inspections of the bearing lugs of the rudder spring tab lever assembly for cracking, and corrective action if necessary. This action is necessary to prevent failure of the rudder flight control system due to such cracking, which could result in loss of rudder control and consequent reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by April 5, 2004.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2003-NM-263-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: 9-anm-nprmcomment@faa.gov. Comments sent via fax or the Internet must contain “Docket No. 2003-NM-263-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 AvCraft Aerospace GmbH, P.O. Box 1103, D-82230 Wessling, Germany. This information may be examined at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington.

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 (425) 227-2125; 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 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-263-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-263-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, notified the FAA that an unsafe condition may exist on all Dornier Model 328-100 and -300 series airplanes. The LBA advises that certain data indicate the possibility of a failure of the rudder flight control system due to cracking in the bearing lugs of the rudder spring tab lever assembly. This condition, if not corrected, could result in loss of rudder control and consequent reduced controllability of the airplane.

Explanation of Relevant Service Information

Dornier has issued Alert Service Bulletin ASB-328-27-036 (for Model 328-100 series airplanes); and Alert Service Bulletin ASB-328J-27-013 (for Model 328-300 series airplanes); both dated February 12, 2003. The service bulletins describe procedures for repetitive inspections which include detailed visual inspections of the edges of the bearing lugs of the rudder spring tab lever assembly for cracking, and eddy current inspections on both bearing lug peripherals for cracking. The service bulletins also describe procedures for corrective action for cracking. The corrective action involves replacement of the rudder spring tab lever assembly with a new assembly if any cracking of the bearing lugs is found, and a functional test of the rudder control system after replacement. Accomplishment of the actions specified in the service bulletins is intended to adequately address the identified unsafe condition. The LBA classified these service bulletins as mandatory and issued German airworthiness directives 2003-383 and 2003-384, both dated November 13, 2003, to ensure the continued airworthiness of these airplanes in Germany.

FAA's Conclusions

These airplane models are manufactured in Germany 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 LBA has kept us informed of the situation described above. We have examined the findings of the LBA, 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 require accomplishment of the actions specified in the service bulletin described previously, except as discussed below.

Differences Among Alert Service Bulletins, German Airworthiness Directives, and Proposed AD

The German airworthiness directives and service bulletins recommend that the inspections of the edges of the bearing lugs of the rudder spring tab lever assembly be repeated at every C-check; however, the repetitive intervals required by this proposed AD are specified as every 24 months, which generally corresponds to an operator's C-check schedule. We have determined that these repetitive intervals represent the maximum interval of time allowable for affected airplanes to continue to operate, prior to accomplishing the required inspections, without compromising safety. Because maintenance schedules may vary from operator to operator, there would be no assurance that inspections accomplished according to a particular operator's C-check schedule would be accomplished during the maximum allowable intervals.

The service bulletins recommend reporting crack findings to the manufacturer, but this proposed AD does not contain such a requirement. In addition, the service bulletins recommend returning damaged lever assemblies to the manufacturer, but this proposed AD does not contain such a requirement.

Whereas the service bulletins specify a detailed visual inspection of the rudder spring tab lever assembly, this proposed AD would require a detailed inspection. A note has been added to define that inspection.

Cost Impact

We estimate that 112 airplanes of U.S. registry would be affected by this proposed AD, that it would take about 1 work hour per airplane to do the proposed inspections, and that the average labor rate is $65 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $7,280, or $65 per airplane, per inspection cycle.

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.

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.