04-49. 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 replacement of the existing main landing gear (MLG) leg assembly with a modified assembly. This action is necessary to prevent fatigue damage of the MLG leg, which could result in collapse of the MLG. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by February 4, 2004.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-400-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 [phone]. Comments may also be sent via the Internet using the following address: [e-mail]. Comments sent via fax or the Internet must contain “Docket No. 2001-NM-400-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:

Tom Groves, 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

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 2001-NM-400-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. 2001-NM-400-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 shot-peening, a manufacturing process used to improve fatigue strength, was not done on the main body of certain main landing gear (MLG) leg assemblies. This condition, if not corrected, could lead to fatigue damage of the MLG leg assembly, which could result in collapse of the MLG.

Explanation of Relevant Service Information

Dornier has issued Service Bulletin SB-328-32-344, Revision 1, dated June 11, 2001, which describes procedures for replacement of the existing MLG leg assembly with an MLG assembly having a shot-peened main body. That service bulletin refers to Messier-Dowty Service Bulletin 800-32-028, dated November 27, 2000, as the appropriate source of service information for shot-peening the main body of the MLG leg. The Dornier Service Bulletin also specifies that Messier-Dowty Service Bulletin 800-32-014, dated January 18, 1999, must be accomplished on the MLG leg assembly at the same time as the other Messier-Dowty service bulletin (unless accomplished previously). Messier-Dowty Service Bulletin 800-32-014 describes procedures for replacing existing bushings on the main body and trailing arm of the MLG with improved bushings and installing the new bushings using the heat-and-shrink method instead of bonding.

Accomplishment of the actions specified in Dornier Service Bulletin SB-328-32-344, Revision 1, is intended to adequately address the identified unsafe condition. The LBA classified Dornier Service Bulletin SB-328-32-344, Revision 1, as mandatory and issued German airworthiness directive 2002-001, dated January 10, 2002, 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 the FAA 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.

Cost Impact

We estimate that 53 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 8 work hours per airplane to accomplish the proposed replacement, and that the average labor rate is $65 per work hour. Required parts would be provided by the manufacturer at no charge. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $27,560, or $520 per airplane.

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.

§ 39.13

[Amended]

2. Section 39.13 is amended by adding the following new airworthiness directive:

Fairchild Dornier GmbH (Formerly Dornier Luftfahrt GmbH): Docket 2001-NM-400AD.

Applicability: Model 328-100 series airplanes, certificated in any category, serial numbers (S/Ns) 3005 through 3119 inclusive, equipped with a main landing gear (MLG) leg assembly, main body, or main machined body having a part number (P/N) and S/N listed in Table 1 of this AD.

Table 1.—MLG Leg Assembly, Main Body, and Main Machined Body P/Ns and S/Ns

MLG part name	P/N	S/Ns
Leg assembly	22730-000-02	U16 through U22 inclusive.
Leg assembly	22731-000-02	U16 through U22 inclusive.
Main body	22415-000-01	U16 through U22 inclusive.
Main body	22416-000-01	U16 through U22 inclusive.
Main machined body	24284-000-00	U56, U62, U64, U66, U68, U70, U74.
Main machined body	22286-000-00	U51, U57, U59, U65, U67, U73, U85.

Compliance: Required as indicated, unless accomplished previously.

To prevent fatigue damage of the MLG leg, which could result in collapse of the MLG, accomplish the following:

Replacement of MLG Leg Assembly

(a) Prior to the accumulation of 16,000 total landings on the MLG body, or within 300 flight hours after the effective date of this AD, whichever occurs later, replace the existing MLG leg assembly with a modified leg assembly per Dornier Service Bulletin SB-328-32-344, Revision 1, dated June 11, 2001.

Note 1:

Dornier Service Bulletin SB-328-32-344, Revision 1, refers to Messier-Dowty Service Bulletins 800-32-028, dated November 27, 2000; and 800-32-014, dated January 18, 1999; as appropriate sources of service information for modifying the MLG leg assembly.

Alternative Methods of Compliance

(b) In accordance with 14 CFR 39.19, the Manager, International Branch, ANM-116, Transport Airplane Directorate, FAA, is authorized to approve alternative methods of compliance for this AD.

Note 2:

The subject of this AD is addressed in German airworthiness directive 2002-001, dated January 10, 2002.

Issued in Renton, Washington, on December 29, 2003.

Ali Bahrami,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.