AD 2000-26-13

This amendment adopts a new airworthiness directive (AD) that is applicable to all Dornier Model 328-300 series airplanes. This action requires inspections of all three hydraulic accumulators for signs of leaks, corrective actions if necessary, and eventual installation of an additional locking device to secure the nuts in the hydraulic accumulators, which will terminate the repetitive inspections. This action is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. This action is necessary to prevent possible loss of one or more of the hydraulic accumulators, which could result in a complete loss of the hydraulic system and consequent reduced controllability of the airplane. This action is intended to address the identified unsafe condition.

Final rule; request for comments

2000-26-13 DORNIER LUFTFAHRT GMBH: Amendment 39-12063. Docket 2000-NM-349-AD.
Applicability: All Model 328-300 series airplanes, 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 possible loss of one or more of the hydraulic accumulators, which could result in a complete loss of the hydraulic system and consequent reduced controllability of the airplane, accomplish the following:

Inspections
(a) Within 3 days after the effective date of this AD, perform a detailed visual inspection of the area around the three hydraulic accumulators for signs of leakage, in accordance with Dornier Alert Service Bulletin ASB-328J-29-006, dated August 31, 2000.

NOTE 2: For the purposes of this AD, a detailed visual inspection is defined as: "An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required."

(1) If no leakage is found: Before further flight, retorque the affected nuts in accordance with the service bulletin and repeat the inspection at least every 5 days thereafter until the requirements of paragraph (b) of this AD have been accomplished.

(2) If leakage is found: Before further flight, perform the modification as specified by paragraph (b) of this AD.

Terminating Modification
(b) Except as required by paragraph (a)(2) of this AD, within 30 days after the effective date of this AD, install an additional locking device to secure the nuts in all three hydraulic accumulators, in accordance with Dornier Alert Service Bulletin ASB-328J-29-006, dated August 31, 2000. Accomplishment of this modification terminates the repetitive inspections required by paragraph (a) of this AD.

Spare Parts
(c) As of the effective date of this AD, no person shall install a hydraulic accumulator tee fitting, part number NAS1764K040404, on any airplane.

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, Transport Airplane Directorate, FAA. 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 3: 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.

Incorporation by Reference
(f) The actions shall be done in accordance with Dornier Alert Service Bulletin ASB-328J-29- 006, dated August 31, 2000. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from FAIRCHILD DORNIER, DORNIER Luftfahrt GmbH, P.O. Box 1103, D-82230 Wessling, Germany. Copies may be inspected 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.

NOTE 4 : The subject of this AD is addressed in German airworthiness directive 2000-314, dated September 14, 2000.

Effective Date
(g) This amendment becomes effective on January 17, 2001.

The Luftfahrt-Bundesamt (LBA), which is the airworthiness authority for Germany, notified the FAA that an unsafe condition may exist on all Dornier Model 328-300 series airplanes. The LBA advised that it has received a total of four reports of hydraulic leaks, discovered during inspection or discovered because "Hydraulic Low Quantity" was indicated on the engine indication and crew alerting system (EICAS). Further investigation revealed loose nuts in the hydraulic accumulators. The cause of the loose nuts has not been determined. This condition, if not corrected, could result in possible loss of one or more of the hydraulic accumulators, which could then result in a complete loss of the hydraulic system and consequent reduced controllability of the airplane.

Explanation of Relevant Service Information
Dornier has issued Alert Service Bulletin ASB-328J-29-006, dated August 31, 2000, which describes procedures for repetitive detailed visual inspections to detect leakage in the area around the three hydraulic accumulators. The service bulletin also describes procedures for a modification, which involves installing an additional locking device to secure the nuts at all three hydraulic accumulators. The modification is recommended as corrective action for leakage, and would eliminate the need for repetitive inspections. The LBA classified this service bulletin as mandatory and issued German airworthiness directive 2000-314, dated September 14, 2000, in order 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. The FAA hasexamined 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 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, this AD is being issued to prevent possible loss of one or more of the hydraulic accumulators, which could result in a complete loss of the hydraulic system and consequent reduced controllability of the airplane. This AD requires accomplishment of the actions specified in the previously described service bulletin.

Determination of Rule's Effective Date
Since a situation exists that requires the immediate adoption of this regulation, it is found that notice and opportunity for prior public comment hereon are impracticable, and that good cause exists for making this amendment effectivein less than 30 days.

Comments Invited
Although this action is in the form of a final rule that involves requirements affecting flight safety and, thus, was not preceded by notice and an opportunity for public comment, comments are invited on this rule. Interested persons are invited to comment on this 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 under the caption "ADDRESSES." All communications received on or before the closing date for comments will be considered, and this rule may be amended in light of the comments received. Factual information that supports the commenter's ideas and suggestions is extremely helpful in evaluating the effectiveness of the AD action and determining whether additional rulemaking action would be needed.

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 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 rule that might suggest a need to modify the 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 that summarizes each FAA-public contact concerned with the substance of this AD will be filed in the Rules Docket.

Commenters wishing the FAA to acknowledge receipt of their comments submitted in response to this rule must submit a self-addressed, stamped postcard on which the following statement is made: "Comments to Docket Number 2000-NM-349-AD." The postcard will be date stamped and returned to the commenter.

Regulatory Impact
The regulations adopted herein will 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 final rule does not have federalism implications under Executive Order 13132.

The FAA has determined that this regulation is an emergency regulation that must be issued immediately to correct an unsafe condition in aircraft, and that it is not a "significant regulatory action" under Executive Order 12866. It has been determined further that this action involves an emergency regulation under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979). If it is determined that this emergency regulation otherwise would be significant under DOT Regulatory Policies and Procedures, a final regulatory evaluation will be prepared and placed in the Rules Docket. A copy of it, if filed, may be obtained from the Rules Docket at the location provided under the caption "ADDRESSES."

List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment
Accordingly, pursuant to the authority delegated to me by the Administrator, the Federal Aviation Administration amends 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: