Daily Rules, Proposed Rules, and Notices of the Federal Government
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We received more than 10 reports of smoke/fire (3 reports of fire) in the tailcone on Cessna Aircraft Company (Cessna) 525, 550, and 560 airplanes, where investigation revealed brushes had worn beyond their limits on the part number (P/N) 1134104-1 A/C compressor motors. When the brush wears down, the rivet in the brush contacts the commutator, causing sparks (potential ignition source) and excessive heat build-up within the motor assembly. The A/C motor is located in the tailcone where flammable fluids are present (fuel lines and some hydraulics) on the Cessna airplanes. There is no fire detection or fire extinguishing equipment in the tailcone.
This condition, if not corrected, could result in a fire in the tailcone with no means to detect or extinguish it.
We are proposing this AD because we evaluated all the relevant information and determined the unsafe condition described previously is likely to exist or develop in other products of the same type design.
This proposed AD would require repetitive inspection of the compressor hour meter on Cessna Model 525 airplanes that have P/N 1134104-1 or 1134104-5 A/C compressor motor installed; an aircraft logbook check for an entry for replacing the brushes, compressor motor, or compressor condenser module assembly (pallet); and replacement of the brushes on the A/C motor or deactivation of the A/C system with installation of a placard prohibiting use of the A/C system until replacement of the brushes. This proposed AD would also require, when the brushes are replaced, reporting of aircraft information related to the replacement of the brushes. The FAA is analyzing this unsafe condition on airplanes certificated under 14 CFR part 25 and may take AD action on those airplanes.
The reporting data required by this proposed AD will enable us to obtain better insight into brush wear. The reporting data will also indicate if the replacement intervals we established are adequate. After we analyze the reporting data received, we may take future rulemaking action.
We estimate that this proposed AD affects 408 airplanes of U.S. registry.
We estimate the following costs to comply with this proposed AD:
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.
We determined that this proposed AD would not have federalism implications under Executive Order 13132. This proposed AD would 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 proposed regulation:
(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),
(3) Will not affect intrastate aviation in Alaska, and
(4) 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.
Air transportation, Aircraft, Aviation safety, Incorporation by reference, Safety.
Accordingly, under the authority delegated to me by the Administrator, the FAA proposes to amend 14 CFR part 39 as follows:
1. The authority citation for part 39 continues to read as follows:
49 U.S.C. 106(g), 40113, 44701.
2. The FAA amends § 39.13 by adding the following new airworthiness directive (AD):
We must receive comments by October 9, 2012.
This AD applies to Cessna Aircraft Company Model 525 airplanes, serial number (S/N) 525-0001 through 525-0558, and 525-0600 through 525-0701, that
(1) are equipped with part number (P/N) 1134104-1 or 1134104-5 air conditioning (A/C) compressor motor; and
(2) are certificated in any category.
Joint Aircraft System Component (JASC)/Air Transport Association (ATA) of America Code 21, Air Conditioning.
This AD was prompted by reports of smoke and/or fire in the tailcone caused by brushes wearing beyond their limits on the A/C motor. We are issuing this AD to require replacement of the brushes on certain P/N A/C compressor motors or deactivation of the A/C system until replacement of the brushes. This AD also requires reporting of aircraft information related to the replacement of the brushes.
Comply with this AD within the compliance times specified, unless already done.
Within the next 30 days after the effective date of this AD or within the next 10 hours time-in-service (TIS) after the effective date of this AD, whichever occurs first, do the following:
(1) Inspect the number of hours on the A/C compressor hour meter; and
(2) Check the aircraft logbook for any entry for replacing the A/C compressor motor brushes with new brushes or replacing the compressor motor or compressor condenser module assembly (pallet) with a motor or assembly that has new brushes.
(i) If the logbook contains an entry for replacement of parts as specified in the paragraph above, determine the number of hours on the A/C compressor motor brushes by comparing the number of hours on the compressor motor since replacement and use this number in paragraph (h) of this AD; or
(ii) If through the logbook check you cannot positively determine the number of hours on the A/C compressor motor brushes as specified in the paragraph above, you must use the number of hours on the A/C compressor hour meter to comply with the requirements of this AD or presume the brushes have over 500 hours TIS and use this number in paragraph (h) of this AD.
At the later of the times specified in paragraph (h)(1) and (h)(2) of this AD, using the hour reading on the A/C compressor hour meter determined in paragraph (g) of this AD, replace the A/C compressor motor brushes with new brushes. Thereafter, repeat the replacement of the A/C compressor motor brushes no later than every 500 hours TIS on the A/C compressor motor. Do the replacement following Cessna Aircraft Company Model 525 Maintenance Manual, Revision 23, dated July 1, 2012.
(1) Before or when the A/C compressor motor brushes reach a total of 500 hours TIS; or
(2) Before further flight after the inspection required in paragraph (g) of this AD.
(1) In lieu of replacing the A/C compressor motor brushes, before or when the A/C compressor motor brushes reach a total of 500 hours TIS, you may deactivate the A/C. Pull the vapor cycle A/C circuit breaker, install a placard by the A/C selection switch prohibiting use of the vapor cycle air conditioner, and document deactivation of the system in the aircraft logbook referring to this AD as the reason for deactivation. While the system is deactivated, aircraft operators must remain aware of operating temperature limitations as detailed in the specific airplane flight manual.
(2) If you choose to deactivate the system and then later choose to return the A/C to service: Before returning the A/C system to
For the first two A/C compressor motor brush replacement cycles on each aircraft, within 30 days after the replacement or within 30 days after the effective date of this AD, whichever occurs later, send the brushes that were removed to Cessna Aircraft Company, Cessna Service Parts and Programs, 7121 Southwest Boulevard, Wichita, KS 67215. Provide the following information with the brushes:
(1) The Model and S/N of the airplane;
(2) P/N of Motor;
(3) P/N of the brushes, if known;
(4) The elapsed amount of motor hours since the last brush/motor replacement, if known;
(5) If motor hours are unknown, report the elapsed airplane flight hours since the last brush/motor replacement and indicate that motor hours are unknown; and
(6) Number of motor hours currently displayed on the pallet hour meter.
Special flight permits are permitted with the following limitation: Operation of the A/C system is prohibited.
A federal agency may not conduct or sponsor, and a person is not required to respond to, nor shall a person be subject to a penalty for failure to comply with a collection of information subject to the requirements of the Paperwork Reduction Act unless that collection of information displays a current valid OMB Control Number. The OMB Control Number for this information collection is 2120-0056. Public reporting for this collection of information is estimated to be approximately 5 minutes per response, including the time for reviewing instructions, completing and reviewing the collection of information. All responses to this collection of information are mandatory. Comments concerning the accuracy of this burden and suggestions for reducing the burden should be directed to the FAA at: 800 Independence Ave. SW., Washington, DC 20591, Attn: Information Collection Clearance Officer, AES-200.
(1) The Manager, Wichita Aircraft Certification Office, FAA, has the authority to approve AMOCs for this AD, if requested using the procedures found in 14 CFR 39.19. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD.
(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office.
For more information about this AD, contact Christine Abraham, Aerospace Engineer, Wichita ACO, FAA, 1801 Airport Road, Room 100, Wichita, Kansas 67209; phone: (316) 946-4165; fax: (316) 946-4107; email: