AD 2007-01-14

The FAA is adopting a new airworthiness directive (AD) for certain Bombardier Model DHC-8-400 series airplanes. This AD requires revising the Airworthiness Limitations Items (ALI) of the maintenance requirements manual to require additional inspection requirements of the maintenance requirements manual for certain principal structural elements (PSEs) related to fuselage cutouts and to reduce an inspection threshold for an existing ALI task on the aft entry door. This AD results from data obtained from the manufacturer's fatigue testing. We are issuing this AD to detect and correct fatigue cracking of certain PSEs, which could result in reduced structural integrity of the airplane.

Final rule.

2007-01-14 Bombardier, Inc. (Formerly de Havilland, Inc.): Amendment 39-14886. FAA-2006-26217; Directorate Identifier 2006-NM-209-AD.

Effective Date

(a) This AD becomes effective March 6, 2007.

Affected ADs

(b) None.

Applicability

(c) This AD applies to Bombardier Model DHC-8-400 series airplanes, serial numbers 4001, 4003, 4004, 4006, and 4008 through 4126 inclusive, certificated in any category.

Unsafe Condition

(d) This AD results from data obtained from the manufacturer's fatigue testing. We are issuing this AD to detect and correct fatigue cracking of certain principal structural elements, which could result in reduced structural integrity of the airplane.

Compliance

(e) You are responsible for having the actions required by this AD performed within the compliance times specified, unless the actions have already been done.

Note 1: This AD requires revisions to certain operator maintenance documents to include new inspections. Compliance with these inspections is required by 14 CFR 91.403(c). For airplanes that have been previously modified, altered, or repaired in the areas addressed by these inspections, the operator may not be able to accomplish the inspections described in the revisions. In this situation, to comply with 14 CFR 91.403(c), the operator must request approval for an alternative method of compliance according to paragraph (g) of this AD. The request should include a description of changes to the required inspections that will ensure the continued damage tolerance of the affected structure. The FAA has provided guidance for this determination in Advisory Circular (AC) 25-1529-1.

Maintenance Requirements Manual Revision

(f) Within 60 days after the effective date of this AD, revise the Airworthiness Limitations Items (ALI), Part 2, Section 2, of the Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1-84-7, by incorporating the information in Bombardier Q400 Dash 8 Temporary Revisions (TR) ALI-53, dated February 16, 2006; and ALI-54, dated March 27, 2006. Thereafter, except as provided in paragraph (g) of this AD, no alternative structural inspection intervals may be approved for the fuselage and doors as specified in the TRs.

Note 2: The actions required by paragraph (f) of this AD may be done by inserting copies of TR ALI-53, dated February 16, 2006, and TR ALI-54, dated March 27, 2006; into the ALI, Part 2, Section 2, of the Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1- 84-7. When TRs ALI-53 and ALI-54 have been included in the general revisions of the maintenance requirements manual, the general revisions may be inserted into the maintenance requirements manual, provided the relevant information in the general revision is identical to that in TRs ALI-53 and ALI-54.

Alternative Methods of Compliance (AMOCs)

(g)(1) The Manager, New York Aircraft Certification Office (ACO), FAA, has the authority to approve AMOCs for this AD,if requested in accordance with the procedures found in 14 CFR 39.19.

(2) Before using any AMOC approved in accordance with Sec. 39.19 on any airplane to which the AMOC applies, notify the appropriate principal inspector in the FAA Flight Standards Certificate Holding District Office.

Related Information

(h) Canadian airworthiness directive CF-2006-10, dated May 12, 2006, also addresses the subject of this AD.

Material Incorporated by Reference

(i) You must use Bombardier Q400 Dash 8 Temporary Revision ALI- 53, dated February 16, 2006, to the Airworthiness Limitations Items, Part 2, Section 2, of the Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1-84-7; and Bombardier Q400 Dash 8 Temporary Revision ALI-54, dated March 27, 2006, to the Airworthiness Limitations Items, Part 2, Section 2, of the Bombardier Q400 Dash 8 Maintenance Requirements Manual, PSM 1-84-7; to perform the actions that are required by this AD, unless the AD specifies otherwise. The Director of the Federal Register approved the incorporation by reference of these documents in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Contact Bombardier, Inc., Bombardier Regional Aircraft Division, 123 Garratt Boulevard, Downsview, Ontario M3K 1Y5, Canada, for a copy of this service information. You may review copies at the Docket Management Facility, U.S. Department of Transportation, 400 Seventh Street, SW., Room PL-401, Nassif Building, Washington, DC; on the Internet at http://dms.dot.gov; or at the National Archives and Records Administration (NARA). For information on the availability of this material at the NARA, call (202) 741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html .

Examining the Docket

You may examine the airworthiness directive (AD) docket on the Internet at http://dms.dot.gov or in person at the Docket Management Facility office between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Management Facility office (telephone (800) 647-5227) is located on the plaza level of the Nassif Building at the street address stated in the ADDRESSES section.

Discussion

The FAA issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an AD that would apply to certain Bombardier Model DHC-8-400 series airplanes. That NPRM was published in the Federal Register on November 2, 2006 (71 FR 64482). That NPRM proposed to require revising the Airworthiness Limitations Items (ALI) of the maintenance requirements manual to require additional inspection requirements of the maintenance requirements manual for certain principal structural elements (PSEs) related to fuselage cutouts and to reduce an inspection threshold for an existing ALI task on the aft entry door.

Comments

We provided the public the opportunity to participate in the development of this AD. We received no comments on the NPRM or on the determination of the cost to the public.

Conclusion

We have carefully reviewed the available data and determined that air safety and the public interest require adopting the AD as proposed.

Costs of Compliance

This AD affects about 21 airplanes of U.S. registry. The required actions take about 1 work hour per airplane, at an average labor rate of $80 per work hour. Based on these figures, the estimated cost of this AD for U.S. operators is $1,680, or $80 per airplane.

Authority for this Rulemaking

Title 49 of the United States Code specifies the FAA's authority to issue rules on aviation safety. Subtitle I, Section 106, describes the authority of the FAA Administrator. Subtitle VII, Aviation Programs, describes in more detail the scope of the Agency's authority.

We are issuing this rulemaking under the authority described in Subtitle VII, Part A, Subpart III, Section 44701, "General requirements.'' Under that section, Congress charges the FAA with promoting safe flight of civil aircraft in air commerce by prescribing regulations for practices, methods, and procedures the Administrator finds necessary for safety in air commerce. This regulation is within the scope of that authority because it addresses an unsafe condition that is likely to exist or develop on products identified in this rulemaking action.

Regulatory Findings

We have determined that this AD will not have federalism implications under Executive Order 13132. This AD 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.

For the reasons discussed above, I certifythat this AD:

(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.

We prepared a regulatory evaluation of the estimated costs to comply with this AD and placed it in the AD docket. See the ADDRESSES section for a location to examine the regulatory evaluation.

List of Subjects in 14 CFR Part 39

Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.

Adoption of the Amendment

Accordingly, under the authority delegated to me by the Administrator, the FAA amends 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.

Sec. 39.13 [Amended]

2. The Federal Aviation Administration (FAA) amends Sec. 39.13 by adding the following new airworthiness directive (AD):