A proposal to amend part 39 of the Federal Aviation Regulations (14 CFR part 39) to include an airworthiness directive (AD) that is applicable to certain Bombardier Model DHC-8-102 airplanes was published in the Federal Register on April 7, 2004 (69 FR 18306). That action proposed to require modification of the electrical power circuit.
Comments
Interested persons have been afforded an opportunity to participate in the making of this amendment. Due consideration has been given to the single comment received.
Request To Give Credit for Modification Using Alternate Service Information
The commenter, an operator, requests that a paragraph be added to the proposed AD giving credit for reconfiguring the circuit breaker wiring as specified in Allied Signal RDS-86 Weather Radar System Manual 006-05996-0005, Revision 5 or higher. The commenter states that it has operated the affected Model DHC-8-102 airplanes continually since 1986, and that the performance of the RDS-86 weather radar system made consultation with the airplane and equipment manufacturers necessary. In 1996, the commenter reconfigured certain circuit breakers for the weather radar system per the equipment manufacturer's recommendations. The commenter notes that the airplane manufacturer did not provide documentation for this change until 2002, when it issued Bombardier Modification Summary Package (ModSum) IS8Q3450000, Revision A, dated October 15, 2002, which the proposed AD references as the appropriate source of service information for the proposed requirements.
The FAA does not agree. It is important to maintain proper configuration of airplane wiring to ensure proper airplane maintenance by operators. The final rule requires modification of the power circuit per ModSum IS8Q3450000, Revision A. The ModSum identifies three installation configurations, and the ModSum installation instructions identify the correct interface buses to be modified and wires tobe reconfigured. The Allied Signal RDS-86 Weather Radar System Manual shows only pin connections of the indicator and receiver/transmitter without any details of unique airplane interconnections. Such limited information provides no means of showing that appropriate wiring changes have been made and is insufficient to demonstrate that the unsafe condition has been addressed properly. We have not changed the final rule in this regard. However, under the provisions of paragraph (b) of the final rule, we may consider requests for approval of an alternative method of compliance if sufficient data are submitted to substantiate that such a design change would provide an acceptable level of safety.
Conclusion
After careful review of the available data, including the comment noted above, the FAA has determined that air safety and the public interest require the adoption of the rule as proposed.
Cost Impact
The FAA estimates that 48 airplanes of U.S. registry will be affected by this AD, that it will take between 3 work hours and 9 work hours per airplane to accomplish the required actions, and that the average labor rate is $65 per work hour. Required parts will cost approximately $150 per airplane. Based on these figures, the cost impact of the AD on U.S. operators is estimated to be between $16,560 and $35,280, or between $345 and $735 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. 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 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.
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 Subjectsin 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.
Sec. 39.13 [Amended]
2. Section 39.13 is amended by adding the following new airworthiness directive: