Airworthiness Directives; Dornier Model 328-100 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 certain Dornier Model 328-100 series airplanes. This proposal would require repetitive inspections of certain support arms of the ground spoiler assemblies for cracking, and replacement of any ground spoiler assembly having cracking with a new ground spoiler assembly. This proposal would also require certain inspections for discrepancies of the ground spoiler assemblies and the flap of each wing; and corrective actions if necessary. This action is necessary to prevent failure of the support arms due to cracking, which could result in loss of function and/or separation of the affected ground spoiler assemblies from the airplane, and consequent reduced controllability of the airplane during landing or rejected take-off operations. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by February 26, 2004.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2002-NM-30AD, 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. 2002-NM-300-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 2002-NM-300-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. 2002-NM-300-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 certain Dornier Model 328-100 series airplanes. The LBA advises that cracking has been found in support arms No. 3 and No. 8 on ground spoiler assemblies No. 1 and No. 2, part numbers 001B577A1000 and 001B577A1100. The cracking is caused by higher loads placed on the support arms as a result of insufficient clearance between the bottom of the trailing edges of the ground spoilers and the upper surfaces of the wing flaps. This condition, if not corrected, could result in loss of function and/or separation of the affected ground spoiler assemblies from the airplane, and consequent reduced controllability of the airplane during landing or rejected take-off operations.

Explanation of Relevant Service Information

Dornier has issued Service Bulletin SB-328-57-435, Revision 1, dated August 7, 2002, which describes procedures for repetitive eddy current inspections to detect cracking in the bottom edge of the flange for ground spoiler support arms No. 3 and No. 8 of ground spoiler assemblies No. 1 and No. 2, part numbers 001B577A1000 and 001B577A1100, left and right sides of the airplane; and replacement of any ground spoiler assembly having cracking with a new ground spoiler assembly.

Dornier has also issued Service Bulletin SB-328-57-439, Revision 1, dated March 10, 2003, which describes procedures for a visual inspection, contour inspection, and clearance inspection of the ground spoilers and the flap of each wing for discrepancies, and corrective action if necessary. The service bulletin includes the following:

• Procedures for a visual inspection of the flap protection strip for chafing marks, reporting inspection results to the manufacturer, and inspecting the bottom surface of the ground spoiler and the mating upper surface of the flap of each wing for surface damage (chafing marks or paint damage), and repair if necessary. If abnormal chafing marks are found, the service bulletin recommends doing the inspection of the spoiler arms per Dornier Service Bulletin SB-328-57-435, Revision 1, dated August 7, 2002.
• Procedures for a contour inspection of the ground spoiler and the flap of each wing to determine if they are within the specified tolerances, adjusting the ground spoiler actuator if out of tolerance, and reporting the inspection results to the manufacturer.
• Procedures for a clearance inspection between the bottom of the trailing edge of the ground spoiler and the upper surface of the flap of each wing. If there is a notable deflection (spring back effect) between the ground spoiler and the surface, the service bulletin recommends reporting the inspection results to the manufacturer. If there is no notable deflection (spring back effect) between the ground spoiler and the surface, the service bulletin recommends adjusting the ground spoiler actuator and repeating the clearance inspection.

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 2002-258, dated September 5, 2002, and 2003-357, dated November 11, 2003, to ensure the continued airworthiness of these airplanes in Germany.

FAA's Conclusions

This airplane model is manufactured in Germany and is 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 AD

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 bulletins described previously, except as discussed below.

Differences Between the Proposed AD, German Airworthiness Directive, and Service Information

Operators should note that Service Bulletin SB-328-57-439, Revision 1, dated March 10, 2003, recommends doing the actions in the service bulletin “as soon as possible or at the latest at the next A-check or equivalent.” German airworthiness directive 2003-357, dated November 11, 2003, recommends doing the actions “at latest at the next A-Check or equivalent.” Because “A-check” schedules vary among operators, this proposed AD would require accomplishment of the actions within 400 flight cycles after the effective date of this proposed AD, and accomplishment of any required corrective action before further flight. We find that compliance of within 400 flight cycles after the effective date of this proposed AD is appropriate for affected airplanes to continue to operate without compromising safety.

Service Bulletin SB-328-57-435, Revision 1, states to contact Dornier if any crack is found in a support arm for a ground spoiler, and to send the affected ground spoiler to Dornier, but those actions are not required by this proposed AD. Service Bulletin SB-328-57-439, Revision 1, also recommends that inspection results for cracking of support arms be sent to Dornier, but that action is not required by this proposed AD.

Clarification of Procedures for Installing New Ground Spoiler

Service Bulletin SB-328-57-435, Revision 1, specifies that if a crack is found in a support arm of a ground spoiler during any inspection, the ground spoiler should be replaced with a new ground spoiler. However, the service bulletin does not include procedures for replacing the ground spoiler. This proposed AD specifies that any ground spoiler replacement should be done per the applicable section(s) of chapters 27 or 57 of the maintenance manual.

Cost Impact

We estimate that 53 airplanes of U.S. registry would be affected by this proposed AD.

It would take approximately 2 work hours per airplane to accomplish the proposed general visual, contour, and clearance inspections of the ground spoilers, at an average labor rate of $65 per work hour. Based on these figures, the cost impact of these proposed inspections on U.S. operators is estimated to be $6,890, or $130 per airplane.

It would take approximately 4 work hours per airplane to accomplish the proposed inspection of the support arms for the ground spoilers, at an average labor rate of $65 per work hour. Based on these figures, the cost impact of this proposed inspection on U.S. operators is estimated to be $13,780, or $260 per airplane.

The cost impact figures discussed above are 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.