AD 98-21-04

This amendment supersedes an existing airworthiness directive (AD), applicable to all Dornier Model 328-100 series airplanes, that currently requires repetitive visual inspections for signs of fuel leakage on the outer wing beginning with Rib 21 and continuing outward; and corrective action, if necessary. This amendment adds a requirement for modification of the lower panels of the outer wing area, which terminates the repetitive inspection requirements. This action also limits the applicability of the existing AD. This amendment is prompted by issuance of mandatory continuing airworthiness information by a foreign civil airworthiness authority. The actions specified by this AD are intended to prevent fuel leakage on the outboard wing, which could result in a fuel explosion and fire.

Final rule

98-21-04 DORNIER LUFTFAHRT GMBH: Amendment 39-10812. Docket 98-NM-173-AD. Supersedes AD 98-04-06, amendment 39-10319.
Applicability: Model 328-100 series airplanes, serial numbers 3005 through 3098 inclusive, excluding serial number 3089; 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 (c)(1) 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 fuel leakage on the outboard wing, which could result in a fuel explosion and fire, accomplish the following:

RESTATEMENT OF REQUIREMENTS OF AD 98-04-06:
(a) Within 30 days after February 25, 1998 (the effective date of AD 98-04-06, amendment 39-10319), perform a visual inspection of the left- and right-hand outer wings, beginning with Rib 21 and continuing outward, for signs of fuel leakage, in accordance with Dornier Alert Service Bulletin ASB-328-57-020, dated October 28, 1997. If any sign of fuel leakage is detected, prior to further flight, re-seal the respective fuel tank in accordance with the alert service bulletin. Repeat the inspection at intervals not to exceed 1,500 flight hours or 6 months, whichever occurs first, until the actions required by paragraph (b) of this AD are accomplished.

NEW REQUIREMENTS OF THIS AD:
(b) Within 6 months after the effective date of this AD, drill a drainhole in the lower panels of the left- and right-hand outer wings, in accordance with Dornier Service Bulletin SB-328-57-255, dated January 21, 1998. Accomplishment of the requirements of this paragraph constitutes terminating action for the repetitive inspections required by paragraph (a) of this AD.

(c) (1) 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, FAA, Transport Airplane Directorate. 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.

(c) (2) Alternative methods of compliance, approved previously in accordance with AD 98-04-06, amendment 39-10319, are approved as alternative methods of compliance with this AD.

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.

(d) 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.

(e) The actions shall be done in accordance with Dornier Alert Service Bulletin ASB-328-57-020, dated October 28, 1997, and Dornier Service Bulletin SB-328-57-255, dated January 21, 1998.

(1) The incorporation by reference of Dornier Service Bulletin SB-328-57-255, dated January 21, 1998, is approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51.

(2) The incorporation by reference of Dornier Alert Service Bulletin ASB-328-57-020, dated October 28, 1997, was approved previously by the Director of the Federal Register as of February 25, 1998 (63 FR 6642, February 10, 1998).

(3) 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 3: The subject of this AD is addressed in German airworthiness directive 1998-218, dated May 7, 1998.

(f) This amendment becomes effective on November 10, 1998.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 98-04-06, amendment 39-10319 (63 FR 6642, February 10, 1998), which is applicable to all Dornier Model 328-100 series airplanes, was published in the Federal Register on August 13, 1998 (63 FR 43347). The action proposed to continue to require repetitive visual inspections for signs of fuel leakage of the outer wing beginning with Rib 21 and continuing outward; and corrective action, if necessary. The action also proposed to add a requirement for modification of the lower panels of the outer wing area, which would terminate the repetitive inspection requirements. In addition, the action proposed to limit the applicability of the existing AD.

Comments
Interested persons have been afforded an opportunity to participate in the making of this amendment. No comments were submitted in response to the proposal or the FAA's determination of the cost to the public.

Conclusion
The FAA has determined that air safety and the public interest require the adoption of the rule as proposed.

Cost Impact
There are approximately 50 airplanes of U.S. registry that will be affected by this AD.

The repetitive inspection that is currently required by AD 98-04-06, and retained in this AD, takes approximately 2 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the currently required inspection on U.S. operators is estimated to be $6,000, or $120 per airplane, per inspection cycle.

The new modification that is required in this AD action takes approximately 7 work hours per airplane to accomplish, at an average labor rate of $60 per work hour. Based on these figures, the cost impact of the modification required by this AD on U.S. operators is estimated to be $21,000, or $420 per airplane.

The cost impact figures discussed above are based on assumptions that no operator has yet accomplished any of the requirements of this AD action, and that no operator would accomplish those actions in the future if this AD were not adopted.

Regulatory Impact
The regulations adopted herein will not have substantial direct effects 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, in accordance with Executive Order 12612, it is determined that this final rule does not have sufficient federalism implications to warrant the preparation of a Federalism Assessment.

For the reasons discussed above, I certify that this action (1) is not a "significant regulatory action" under Executive Order 12866; (2) is not a "significant rule" under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); and (3) 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 final evaluation has been prepared for this action and it is contained in the Rules Docket. A copy of it 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 removing amendment 39-10319 (63 FR 6642, February 10, 1998), and by adding a new airworthiness directive (AD), amendment 39-10812, to read as follows: