AD 98-23-12

This amendment supersedes an existing airworthiness directive (AD), applicable to all de Havilland Model DHC-7 series airplanes, that currently requires certain structural inspections, and repair, if necessary. This amendment requires an additional structural inspection. 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 detect and correct fatigue cracking in certain significant structural areas, which could reduce the structural integrity of these airplanes.

Final Rule

98-23-12 DE HAVILLAND INC.: Amendment 39-10879. 98-NM-143-AD. Supersedes AD 97-06-08, Amendment 39-9965.

Applicability: All Model DHC-7 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 (f) 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 ensure the continued structural integrity of these airplanes, accomplish the following:

RESTATEMENT OF REQUIREMENTS OF AD 97-06-08, AMENDMENT 39-9965:
(a) Within 6 months after April 21, 1997 (the effective date of AD 97-06-08, amendment 39-9965), incorporate into the FAA-approved maintenance inspection program the inspections and inspection intervals defined in DHC-7 Maintenance Manual, Product Support Manual (PSM) 1-7-2, Chapter 5-60-00, Temporary Revision TR 5-84, dated June 15, 1994; and inspect the significant structural items prior to the thresholds specified in TR 5-84 of PSM 1-7-2. Repeat the inspections thereafter at the intervals specified in TR 5-84 of PSM 1-7-2.

(b) Prior to further flight, repair any discrepancies detected during any inspection required by paragraph (a) of this AD in accordance with one of the following:

(1) The DHC-7 Maintenance Manual; or

(2) The DHC-7 Structural Repair Manual; or

(3) Other data meeting the certificationbasis of the airplane approved by the Manager, New York Aircraft Certification Office (ACO), FAA, Engine and Propeller Directorate; or

(4) Data meeting the certification basis of the airplane approved by Transport Canada Aviation.

NEW REQUIREMENTS OF THIS AD:

(c) Incorporate into the FAA-approved maintenance inspection program the inspections and inspection intervals defined in the de Havilland Inc. DASH 7 Maintenance Manual, Chapter 5, Section 5-60-00, Product Support Manual (PSM) 1-7-2, Supplementary Inspection Program (SIP), Temporary Revision TR 5-99, dated December 22, 1997, at the applicable time specified in paragraph (c)(1) or (c)(2) of this AD; and inspect the significant structural items prior to the thresholds specified in TR 5-99 of PSM 1-7-2. Thereafter, repeat the inspection at the intervals specified in TR 5-99 of PSM 1-7-2.

(1) For airplanes that have accumulated 38,000 or more total flight cycles as of the effective date of this AD: Incorporate within 2,000 flight cycles after the effective date of this AD.

(2) For airplanes that have accumulated fewer than 38,000 total flight cycles as of the effective date of this AD: Incorporate prior to the accumulation of 40,000 total flight cycles.

(d) Incorporate into the FAA-approved maintenance inspection program the inspections and inspection intervals as defined in the de Havilland Inc. DASH 7 Maintenance Manual, Chapter 5, Section 5-60-00, PSM 1-7-2, Supplementary Inspection Program (SIP), Temporary Revision TR 5-97, dated December 22, 1997, at the applicable time specified in paragraph (d)(1) or (d)(2) of this AD; and inspect the significant structural items prior to the thresholds specified in TR 5-97 of PSM 1-7-2. Thereafter, repeat the inspection at the intervals specified in TR 5-99 of PSM 1-7-2.

(1) For airplanes that have accumulated 19,000 or more total flight cycles as of the effective date of this AD: Incorporate within 1,000 flight cycles after the effective date of this AD.

(2) For airplanes that have accumulated fewer than 19,000 total flight cycles as of the effective date of this AD: Incorporate prior to the accumulation of 20,000 total flight cycles.

(e) All inspection results, positive or negative, must be reported to de Havilland in accordance with "Introduction," paragraph 5, of de Havilland Inc. DASH 7 Maintenance Manual Chapter 5, Section 5-60-00, PSM 1-7-2, Temporary Revision TR 5-84, dated June 15, 1994. Information collection requirements contained in this regulation have been approved by the Office of Management and Budget (OMB) under the provisions of the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.) and have been assigned OMB Control Number 2120-0056.

(f) 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, New York Aircraft Certification Office (ACO), FAA, Engine and Propeller Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, New York ACO.

NOTE 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the New York ACO.

(g) 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.

(h) The inspections shall be done in accordance with DHC-7 Maintenance Manual, Product Support Manual (PSM) 1-7-2, Chapter 5-60-00, Temporary Revision TR 5-84, dated June 15, 1994; de Havilland Inc. DASH 7 Maintenance Manual, Chapter 5, Section 5-60-00, Product Support Manual (PSM) 1-7-2, Supplementary Inspection Program (SIP), Temporary Revision TR 5-99, dated December 22, 1997; and de Havilland Inc. DASH 7 Maintenance Manual, Chapter 5, Section 5-60-00, PSM 1-7-2, Supplementary Inspection Program (SIP), Temporary Revision TR 5-97, dated December 22, 1997.

(1) The incorporation by reference of de Havilland Inc. DASH 7 Maintenance Manual, Chapter 5, Section 5-60-00, Product Support Manual (PSM) 1-7-2, Supplementary Inspection Program (SIP), Temporary Revision TR 5-99, dated December 22, 1997; and de Havilland Inc. DASH 7 Maintenance Manual, Chapter 5, Section 5-60-00, Product Support Manual (PSM) 1-7-2, Supplementary Inspection Program (SIP), Temporary Revision TR 5-97, dated December 22, 1997; 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 DHC-7 Maintenance Manual, Product Support Manual (PSM) 1-7-2, Chapter 5-60-00, Temporary Revision TR 5-84, dated June 15, 1994, was approved previously by the Director of the Federal Register as of April 21, 1997 (62 FR 12531, March 17, 1997).

(3) Copies may be obtained from Bombardier, Inc., Bombardier Regional Aircraft Division, Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the FAA, Engine and Propeller Directorate, New York Aircraft Certification Office, 10 Fifth Street, Third Floor, Valley Stream, New York; 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 Canadian airworthiness directive CF-94-19R1, dated January 26, 1998.

(i) This amendment becomes effective on December 17, 1998.

A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) by superseding AD 97-06-08, amendment 39-9965 (62 FR 12531, March 17, 1997), which is applicable to all de Havilland Model DHC-7 series airplanes, was published in the Federal Register on September 3, 1998 (63 FR 46925). The action proposed to continue to require certain structural inspections, and repair, if necessary. The action also proposed to require an additional structural inspection.

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 inspections that are currently required by AD 97-06-08, and retained in this AD, take approximately 15 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 inspections on U.S. operators is estimated to be $45,000, or $900 per airplane, per inspection cycle.

The new inspection that is required by this AD will take approximately 3 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 new inspection required by this AD on U.S. operators is estimated to be $9,000, or $180 per airplane, per inspection cycle.

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 39-9965 (62 FR 12531, March 17, 1997), and by adding a new airworthiness directive (AD), amendment 39-10879, to read as follows: