The FAA proposed to amend 14 CFR part 39 with a proposed AD. The proposed AD applies to McCauley Propeller Systems C406 and C409 propellers, installed on TCM IO-520, TSIO-520, or IO-550 reciprocating engines. We published the proposed AD in the Federal Register on Nov. 16, 2005 (70 FR 69472). That action proposed to require adding an operational RPM restriction on the C406 and C409 propellers, and installing an RPM restriction placard in the cockpit. We coordinated the proposed placard placement with the responsible Aircraft Certification Offices within the Small Airplane Directorate, and all proposed installations include a manifold pressure gauge. That action also proposed to add a 10,000-hour total time-in-service (TIS) life limit for these propellers. That action also proposed to remove from service any propeller that has 10,000 hours or more total TIS, or that has an unknown total TIS. Finally, that action proposed to require initial and repetitive propeller blade inspections for damage, and repair if necessary.
Examining the AD Docket
You may examine the docket that contains the AD, any comments received, and any final disposition in person at the Docket Management Facility between 9 a.m. and 5 p.m., Monday through Friday, except Federal holidays. The Docket Office (telephone (800) 647-5227) is located on the plaza level of the Department of Transportation Nassif Building at the street address stated in ADDRESSES. Comments will be available in the AD docket shortly after the DMS receives them.
Comments
We provided the public the opportunity to participate in the development of this AD. We have considered the comments received.
Financial Burden and Potential Unsafe Condition
One commenter states that this AD will impose a financial burden on owners and operators of airplanes with this propeller installation because of the increased number of inspections and additional wear on the propeller system increasingthe probability of the propeller system failing. The commenter also suggests that stamping a letter on the propeller model to designate a life-limited propeller could create a potentially unsafe condition because the stamping can create stress risers and if improperly treated after stamping, could contribute to corrosion. The commenter also notes that the airplane model designations are incorrect and we omitted one model from the airplane model listing. Finally, the commenter asks why we did not immediately ground the fleet using this propeller because of the described severity of the unsafe condition. We partially agree with the comments. Each is addressed in turn. The increased inspections required by this AD are necessary to resolve the unsafe condition. Owner operators must maintain their aircraft in an airworthy condition, which includes paying for maintenance. We considered that cost and discussed it in the cost section below. We did not change the AD.
This AD will not result in additional wear and tear on the propellers, or in increased failures. This AD resolves an unsafe condition. All actions required are either performed with the propeller installed, or coincident with the next overhaul or major disassembly. An experienced, appropriately rated mechanic can do the inspection and rework without removing the propeller. We did not change the AD.
The manufacturer carefully considered where to stamp the life limit indication to minimize any stress riser. We have no indications that his choice was wrong. We did not change the AD.
We agree that this AD should include additional models. We changed the AD to include the Beech 35-A33 and 35-B33. The Beech 35-A33 and 35- B33 are now included in Applicability paragraph (c) Table (1).
Grounding the fleet that has the suspect propellers installed is not required. The unsafe condition identified is due to material fatigue. The actions required by this AD adequately address the unsafe condition. We didnot change the AD.
Eliminate the Repetitive Inspections of This AD
Another commenter states that the AD does not include a terminating action to eliminate the recurring inspections necessary to comply with it. Even if an operator replaces the existing propeller with a new propeller, the recurring inspections are necessary as long as the replacement propeller is one of same models identified in the airworthiness directive. Additionally, the commenter notes that aircraft performance is also a consideration. This AD will require operating the engine and propeller combination in a less than full engine power regime, which could compromise safety in particular situations associated with departures, arrivals and clearing obstacles. We partially agree.
This AD imposes the RPM and life limit to correct an unsafe condition. The recurring inspections are required to enhance safety. The RPM restriction, imposed propeller life limit, and periodic propeller blade inspection/rework provide a cost effective means to correct the unsafe condition without prematurely retiring the propeller. The RPM restriction does not affect the engine full power ratings. Takeoff, climb, and descent values remain unchanged. Therefore, this AD does not compromise safety during departures, arrivals, and in clearing obstacles. We did not change the AD.
Recall Impacted Propellers
Another commenter believes that the FAA should require a recall of all propeller models listed in the AD so the manufacturer will be responsible for the cost of repair and replacement. We do not agree.
The FAA cannot dictate commercial business decisions related to AD actions. We identified the unsafe condition and are imposing appropriate corrective action. We did not change the AD.
Extend the Comment Period
Two commenters asked that we extend the comment period for the proposed rule to give the general aviation community added time to review non-proprietary data used to substantiate the proposed action and to make additional comments. We agree, and extended the comment period to give the aviation community time to respond. The comments that we responded to above include any additional comments that came in.
Correct Date of Service Bulletin
The proposed rule referenced McCauley Propeller Systems Alert Service Bulletin (ASB) No. ASB248, dated January 17, 2005. The correct date is April 19, 2005. We changed the AD to indicate the correct date of the service bulletin.
Conclusion
We have carefully reviewed the available data, including the comments received, and determined that air safety and the public interest require adopting the AD with the changes described previously. We have determined that these changes will neither increase the economic burden on any operator nor increase the scope of the AD.
Costs of Compliance
This AD will affect about 2,350 C406 and C409 propellers installed on airplanes of U.S. registry. We estimate it will take threework- hours per propeller to perform the proposed inspections and repairs. We also estimate it will take about 0.5 work-hour to install the proposed cockpit placard, and about 950 airplanes will require the placard. The average labor rate is $80 per work-hour. A replacement propeller blade set will cost about $5,200. We estimate 500 propellers in the fleet (or about 21 percent) would require propeller blade set replacement. Based on these figures, we estimate the total cost of the AD to U.S. operators to be $3,202,000.
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 certify that 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 summary of the costs to comply with this AD and placed it in the AD Docket. You may get a copy of this summary at the address listed under ADDRESSES.
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 Federal Aviation Administration 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 airworthiness directive: