Streamlined Issuance of AD
The FAA is implementing a new process for streamlining the issuance of ADs related to MCAI. This streamlined process will allow us to adopt MCAI safety requirements in a more efficient manner and will reduce safety risks to the public. This process continues to follow all FAA AD issuance processes to meet legal, economic, Administrative Procedure Act, and Federal Register requirements. We also continue to meet our technical decision-making responsibilities to identify and correct unsafe conditions on U.S.-certificated products.
This AD references the MCAI and related service information that we considered in forming the engineering basis to correct the unsafe condition. The AD contains text copied from the MCAI and for this reason might not follow our plain language principles.
Discussion
The European Aviation Safety Agency (EASA), which is the technical agent for the Member States of the European Community, has issued EASA Emergency Airworthiness Directive 2007-0039-E, dated February 16, 2007 (referred to after this as "the MCAI''), to correct an unsafe condition for the specified products. The MCAI states:
Following the identification of a failed propeller RPM (revolutions per minute) cable end fitting and an LP (low pressure) fuel lever cable end fitting on an SD3 aircraft, several subsequent occurrences of control cable end fittings (type MS21260) with signs of pitting corrosion or cracking have been reported to Bombardier Shorts. All reported instances being identified during ground maintenance inspections on the SD3 fleet. Bombardier Shorts have performed examinations on the failed cable end fittings and established the root cause of failure as stress corrosion cracking of the SAE-AISI 303 stainless steel material they are manufactured from, initiated by pitting corrosion on the surface. The root cause of the stress corrosion is sustained tensile stress in a corrosive (warm, humid and salty) atmosphere.
An analysis of the cable operated control systems installed on the SD3 aircraft types that use MS 21260 type end fittings has identified a number of potentially unsafe conditions due to a combination of failures that may result from this common mode cause.
The failure of certain control cables could result in the loss of certain critical systems. For example, the loss of the LP fuel control cable in combination with a single failure of a fuel condition control cable on the same engine can cause the loss of the capability to shut down the engine in the event of an engine fire. You may obtain further information by examining the MCAI in the AD docket.
Relevant Service Information
Shorts has issued the following service bulletins. The actions described in this service information are intended to correct the unsafe condition identified in the MCAI.
Shorts Alert Service Bulletin SD3 Sherpa-76-A02, Revision 1, dated January 24, 2007.
ShortsAlert Service Bulletin SD330-76-A09, Revision 1, dated January 24, 2007.
Shorts Alert Service Bulletin SD360 Sherpa-76-A03, Revision 1, dated January 24, 2007.
Shorts Alert Service Bulletin SD360-76-A12, Revision 1, dated January 24, 2007.
FAA's Determination and Requirements of This AD
This product has been approved by the aviation authority of another country, and is approved for operation in the United States. Pursuant to our bilateral agreement with the State of Design Authority, we have been notified of the unsafe condition described in the MCAI and service information referenced above. We are issuing this AD because we evaluated all pertinent information and determined the unsafe condition exists and is likely to exist or develop on other products of the same type design.
Differences Between the AD and the MCAI or Service Information
We have reviewed the MCAI and related service information and, in general, agree with their substance. But we might have found it necessary to use different words from those in the MCAI to ensure the AD is clear for U.S. operators and is enforceable. In making these changes, we do not intend to differ substantively from the information provided in the MCAI and related service information.
We might also have required different actions in this AD from those in the MCAI in order to follow FAA policies. Any such differences are highlighted in a NOTE within the AD.
FAA's Determination of the Effective Date
An unsafe condition exists that requires the immediate adoption of this AD. The FAA has found that the risk to the flying public justifies waiving notice and comment prior to adoption of this rule because of the number of control cable assemblies that were deemed not to be airworthy when evaluated against specific inspection criteria. Therefore, we determined that notice and opportunity for public comment before issuing this AD are impracticable and that good cause exists for making this amendment effective in fewer than 30 days.
Comments Invited
This AD is a final rule that involves requirements affecting flight safety, and we did not precede it by notice and opportunity for public comment. We invite you to send any written relevant data, views, or arguments about this AD. Send your comments to an address listed under the ADDRESSES section. Include "Docket No. FAA-2007-27866; Directorate Identifier 2007-NM-055-AD'' at the beginning of your comments. We specifically invite comments on the overall regulatory, economic, environmental, and energy aspects of this AD. We will consider all comments received by the closing date and may amend this AD because of those comments.
We will post all comments we receive, without change, to http://dms.dot.gov , including any personal information you provide. We will also post a report summarizing each substantive verbal contact we receive about this AD.
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 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 certify this AD:
1. Is not a "significant regulatory action'' under Executive Order 12866;
2. Is not a "significant rule'' under the 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.
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 FAA amends Sec. 39.13 by adding the following new AD: