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 Cessna Model 500, 550, S550, 560, 560XL, and 750 airplanes. That NPRM was published in the Federal Register on September 30, 2005 (70 FR 57213). That NPRM proposed to require installing identification sleeves on the wires for the positive and negative terminal studs of the engine and/or auxiliary power unit (APU) fire extinguishing bottles, as applicable, and re- connecting the wires to the correct terminal studs.
Comments
We provided the public the opportunity to participate in the development of this AD. We have considered the comments received.
Request To Use Parts Other Than Factory Kit
The commenter sees the need for the proposed AD, but does not like the fact that it is tied to a factory service bulletin. The commenter states that the kits specified in the service bulletin that are necessary to do the actions in the NPRM are often out of stock at the manufacturer. The commenter further points out that the actions in the NPRM can be accomplished without waiting for the kit because the actions can be done using standard items and practices in the field. In addition, the commenter states that the kits are much more costly than the estimate provided in the NPRM.
We infer that the commenter is requesting confirmation that the factory-provided kits are available for all affected airplanes to accomplish the required actions, and that the kits will not be morecostly than stated in the NPRM. The manufacturer has assured us that the kits are available and that the parts costs cited in the NPRM are correct. The manufacturer also noted that there is no cost for kits if the affected airplane is within its five-year warranty period. If the commenter has difficulty getting a kit or kits, or wishes to use standard items and practices in the field, the commenter can apply for an alternative method of compliance in accordance with the procedures in paragraph (j) of this AD.
We have not changed the AD in this regard.
Request To Correct Incorrect Statement Regarding Shutoff Valves
Another commenter supports the need for the proposed AD, but states that the "Discussion" section incorrectly indicates that the mis-wiring will cause the shutoff valves for the main engine fuel and hydraulic firewall to open. The commenter suggests that we delete this statement. The commenter explains that the valves are motor-operated and remain in the last position when power is absent. They close in less than one second when the illuminated engine fire light/ switch is pressed, which also arms the circuits for the fire extinguishing bottles, but does not apply power to the fire extinguishing bottles. The commenter states that if the fire extinguishing bottles are mis-wired, the valves would stay closed upon subsequent activation of the fire extinguishing bottle discharge switch and tripping of the circuit breaker. The commenter further states that the valve-closed annunciation would go off when the circuit breaker tripped.
We disagree with the commenter. The tripped circuit breaker removes power from the fuel and hydraulic shutoff valves and the associated cockpit annunciations, except for the Model 750 APU installation. The fuel and hydraulic shutoff valves are powered closed from a normally open state. Cessna has tested the fuel and hydraulic shutoff valves and found that these valves may not close before the circuit breaker tripsand removes power from the valve. Testing also showed that the time required before the circuit breaker trips varies from airplane to airplane. When power is removed, the valves could be in any position ranging from fully opened to fully closed. Therefore, if there is a fire, flammable fluids could continue to be supplied to the fire. As a result of this time variation, we included this condition in the Discussion section of the proposed AD. In addition, the Discussion section of the preamble does not reappear in the final rule. We have not changed the AD in this regard.
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 as proposed.
Costs of Compliance
There are about 2,801 airplanes of the affected design in the worldwide fleet, including about 2,369 airplanes of the affected design of U.S. Registry. The following table provides the estimated costsfor U.S. operators to comply with this AD.
Estimated Costs
Modification for Cessna Model
Work hours
Average labor rate per hour
Parts
Cost per airplane
Number of U.S.-registered airplanes
Fleet cost
500, 550, S550, and 560 airplanes
3
$65
$50
$245
1,827
$447,615
560XL airplanes
4
65
100
360
331
119,160
750 airplanes
2
65
25
155
211
32,705
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 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):