01-23841. 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 certain Dornier Model 328-100 and -300 series airplanes. This proposal would require testing of the left- and right-hand potentiometer levers of the aileron flight control system, and follow-on or corrective action, as applicable. This action is necessary to prevent detachment of an aileron potentiometer lever, which could result in jamming of the elevator and/or aileron flight control systems and consequent reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

DATES:

Comments must be received by October 25, 2001.

ADDRESSES:

Submit comments in triplicate to the Federal Aviation Administration (FAA), Transport Airplane Directorate, ANM-114, Attention: Rules Docket No. 2001-NM-185-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056. Comments may be inspected at this location between 9:00 a.m. and 3:00 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-185-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 for Windows or ASCII text.

The service information referenced in the proposed rule may be obtained from FAIRCHILD DORNIER, DORNIER Luftfahrt 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-185-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-185-AD, 1601 Lind Avenue, SW., Renton, Washington 98055-4056.

Discussion

The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, recently notified the FAA that an unsafe condition may exist on certain Dornier Model 328-100 and -300 series airplanes. The LBA advises that a potentiometer lever without a safety lock function (because of insufficient spline engagement) was found on a manufacturer-owned test airplane. This condition, if not corrected, could cause detachment of an aileron potentiometer lever, which could result in jamming of the elevator and/or aileron flight control systems and consequent reduced controllability of the airplane.

Explanation of Relevant Service Information

The manufacturer has issued Dornier Service Bulletin SB-328-27-359, dated March 29, 2001 (for Model 328-100 series airplanes), and Dornier Service Bulletin SB-328J-27-064, Revision 1, dated April 12, 2001 (for Model 328-300 series airplanes), which describe procedures for testing of the potentiometer levers for security of attachment to the splined shaft and follow-on or corrective actions, as applicable. (Follow-on and corrective actions include replacing the loose lever with a new one if available, or temporarily reassembling the existing lever with loctite until a new one is available). 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 2001-167/2, dated June 28, 2001, and 2001-168, dated June 14, 2001, in order to assure 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 the FAA informed of the situation described above. The FAA has 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 bulletins described previously, except as discussed below.

Differences Between Proposed Rule, Foreign Airworthiness Directives, and Service Bulletins

The parallel German airworthiness directives require testing of the potentiometer levers of the aileron, elevator, and rudder flight control systems, but the proposed AD would only require testing of the potentiometer levers of the aileron flight control system. The FAA has determined that detachment of a potentiometer lever of the aileron flight control system could result in jamming of the aileron and/or elevator control systems. But detachment of a potentiometer lever of the rudder or elevator flight control systems will not introduce an unsafe condition. The German airworthiness directives and Dornier Service Bulletins SB-328-27-359, dated March 29, 2001; and SB-328J-27-064, Revision 1, dated April 12, 2001, included testing of the potentiometer levers of the rudder and elevator control systems for economic reasons, because it takes considerably more time to access the testing area than it does to perform the testing and it is cost-efficient to test the remaining areas once they have been accessed. Because detachment of the potentiometer levers of the rudder and elevator flight control systems will not cause an unsafe condition, however, the proposed AD will not require their testing.

Operators should note that, while no compliance date for replacement of defective levers is specified in German airworthiness directives 2001-167/2, dated June 28, 2001, and 2001-168, dated June 14, 2001, this proposed AD would require, within 30 days after the effective date of the AD, replacement of any defective lever, in accordance with Dornier Service Bulletin SB-328-27-359, dated March 29, 2001; or Dornier Service Bulletin SB-328J-27-064, Revision 1, dated April 12, 2001. If replacement levers are needed but unavailable, this proposed AD would require interim corrective measures and then, within 4,000 flight hours or 24 months from the effective date of the AD, whichever comes first, replacement of any defective lever in a manner approved by the FAA or the LBA (or its delegated agent).

Operators should note that, although Dornier Service Bulletin SB-328-27-359, dated March 29, 2001, specifies that for airplanes on which Dornier Service Bulletin SB-328-27-319 has not been accomplished, testing be performed on the installed nose wheel steering potentiometer, the proposed rule does not require that. The FAA has determined that the unsafe condition does not exist for those airplanes on which Dornier Service Bulletin SB-328-27-319 has not been accomplished.

Operators should also note that, although Dornier Service Bulletin SB-328-27-359, dated March 29, 2001; and Dornier Service Bulletin SB-328J-27-064, Revision 1, dated April 12, 2001, specify that the manufacturer may be contacted for disposition of certain repair conditions, this proposal would require the repair of those conditions to be accomplished per a method approved by either the FAA or the LBA (or its delegated agent). In light of the type of repair that would be required to address the identified unsafe condition, and in consonance with existing bilateral airworthiness agreements, the FAA has determined that, for this proposed AD, a repair approved by either the FAA or the LBA would be acceptable for compliance with this proposed AD.

Cost Impact

The FAA estimates that 89 airplanes of U.S. registry would be affected by this proposed AD, that it would take approximately 2 work hours per airplane to accomplish the proposed test, and that the average labor rate is $60 per work hour. Based on these figures, the cost impact of the proposed AD on U.S. operators is estimated to be $10,680, or $120 per airplane, per test 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 proposed 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:

Dornier Luftfahrt GMBH: Docket 2001-NM-185-AD.

Applicability: Model 328-100 airplanes, serial numbers 3005 through 3119, inclusive, on which Dornier Service Bulletin SB-328-27-319, dated June 26, 2000, or Revision 1, dated September 27, 2000, has been accomplished; and Model 328-300 series airplanes, serial numbers 3105 through 3184, inclusive; certificated in any category.

Note 1:

This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (d) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Compliance: Required as indicated, unless accomplished previously.

To prevent detachment of the aileron potentiometer lever, which could result in jamming of the elevator and/or aileron flight control systems and reduced controllability of the airplane, accomplish the following:

Testing and Corrective Action

(a) Within 30 days after the effective date of this AD, test the left- and right-hand potentiometer levers of the aileron flight control system to determine whether, with the bolt in position and the clamping force across the splines relaxed, the levers can be pulled off the splined shaft, in accordance with the Dornier service bulletin listed in paragraph (a)(1) or (a)(2) of this AD, as applicable.

(1) For Dornier Model 328-100 series airplanes: Accomplishment Instructions, “Aileron System,” of Dornier Service Bulletin SB-328-27-359, dated March 29, 2001.

(2) For Dornier Model 328-300 series airplanes: Accomplishment Instructions, “Aileron System,” of Dornier Service Bulletin SB-328J-27-064, Revision 1, dated April 12, 2001.

(b) If, as a result of the test required by paragraph (a) of this AD, any lever cannot be removed, before further flight, retighten the nut and bolt and replace the split pin, in accordance with the Dornier service bulletin listed in paragraph (a)(1) or (a)(2) of this AD, as applicable.

(c) If, as a result of the test required by paragraph (a) of this AD, any lever can be detached from the splined shaft, perform the actions specified in paragraph (c)(1) or (c)(2) of this AD, as applicable.

(1) If a new lever is available from stock or from the airplane manufacturer, before further flight, replace the defective lever with a new lever, in accordance with the Dornier service bulletin listed in paragraph (a)(1) or (a)(2) of this AD, as applicable and, after the installation of the new lever and before further flight, test the new lever as required in paragraph (a) of this AD.

(2) If a new lever is not available from stock or from the airplane manufacturer, before further flight, reassemble the existing lever with loctite, in accordance with the Dornier service bulletin listed in paragraph (a)(1) or (a)(2) of this AD, as applicable and, within 4,000 flight hours or 24 months after the effective date of this AD, whichever comes first, replace the lever with a new lever in accordance with a method approved by either the Manager, International Branch, ANM-116, FAA, Transport Airplane Directorate; or the Luftfahrt-Bundesamt (LBA) (or its delegated agent).

Alternative Methods of Compliance

(d) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, International Branch, ANM-116. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, International Branch, ANM-116.

Note 2:

Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the International Branch, ANM-116.

Special Flight Permits

(e) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished.

Note 3:

The subject of this AD is addressed in German airworthiness directive 2001-167/2, dated June 28, 2001, and German airworthiness directive 2001-168, dated June 14, 2001.

Issued in Renton, Washington, on September 18, 2001.

Ali Bahrami,

Acting Manager, Transport Airplane Directorate, Aircraft Certification Service.