Airworthiness Directive · Amendment 39-17453 · Air conditioning
Cessna Aircraft Company Airplanes
This AD applies to the following Cessna Aircraft Company airplanes, certificated in any category.
(1) Model 500 and 501 airplanes, serial numbers (S/N) 0001 through 0689 inclusive.
(2) Model 550 and 551 airplanes, S/Ns 0002 through 0733 inclusive, and 0801 through 1136 inclusive.
(3) Model S550 airplanes, S/Ns 0001 through 0160 inclusive.
(4) Model 560 airplanes, S/Ns 0001 through 0707 inclusive, and 0751 through 0815 inclusive.
(5) Model 560XL airplanes, S/Ns 5001 through 5300 inclusive.
(6) Model 650 airplanes, S/Ns 0200 through 0241 inclusive, and 7001 through 7119 inclusive.
We are adopting a new airworthiness directive (AD) for certain Cessna Aircraft Company Model 500, 501, 550, 551, S550, 560, 560XL, and 650 airplanes. This AD was prompted by multiple reports of smoke and/or fire in the tailcone caused by sparking due to excessive wear of the brushes in the air conditioning (A/C) motor. This AD requires inspecting to determine if certain A/C compressor motors are installed and to determine the accumulated hours on certain A/C drive motor assemblies; repetitive replacement of the brushes in the drive motor assembly, or, as an option to the brush replacement, deactivation of the A/C system and placard installation; and return of replaced brushes to Cessna. We are issuing this AD to prevent the brushes in the A/C motor from wearing down beyond their limits, which could result in the rivet in the brush contacting the commutator causing sparks and consequent fire and/or smoke in the tailcone with no means to detect or extinguish the fire and/or smoke.
Within 30 days or 10 flight hours after the effective date of this AD, whichever occurs first: Inspect the A/C compressor motor to determine whether P/N 1134104-1 or P/N 1134104-5 is installed. A review of airplane maintenance records is acceptable in lieu of this inspection if the part number of the A/C compressor motor can be conclusively determined from that review.
If, during the inspection required by paragraph (g) of this AD, any A/C compressor motor is found having P/N 1134104-1 or P/N 1134104-5: Within 30 days or 10 flight hours after the effective date of this AD, whichever occurs first, determine the hour reading on the A/C compressor hour meter as specified in paragraphs (h)(1) and (h)(2) of this AD.
(1) Inspect the number of hours on the A/C compressor hour meter. And,
(2) Check the airplane logbook for any entry for replacing the A/C compressor motor brushes with new brushes, or for 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 paragraph (h)(2) of this AD, 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 lieu of the number determined in paragraph (h)(1) 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 paragraph (h)(2) of this AD, use the number of hours on the A/C compressor hour meter determined in paragraph (h)(1) of this AD or presume the brushes have over 500 hours time-in-service.
Using the hour reading on the A/C compressor hour meter determined in paragraph (h) of this AD, replace the A/C compressor motor brushes with new brushes at the later of the times specified in paragraphs (i)(1) and (i)(2) of this AD. Thereafter, repeat the replacement of the A/C compressor motor brushes at intervals not to exceed 500 hours time-in-service on the A/C compressor motor. Do the replacement in accordance with the applicable Cessna maintenance manual subject specified in paragraphs (j)(1) through (j)(7) of this AD.
(1) Before the accumulation of 500 total hours time-in-service on the A/C compressor motor.
(2) Before further flight after doing the inspection required in paragraph (h) of this AD.
Use the instructions in the applicable Cessna maintenance manual subject specified in paragraphs (j)(1) through (j)(7) of this AD to do the replacement required by paragraph (i) of this AD.
(1) Subject 4-11-00, Replacement Time Limits, of Chapter 4, Airworthiness Limitations, Revision 10, dated April 23, 2012, of the Cessna Model 550 Bravo Maintenance Manual.
(2) Subject 4-11-00, Replacement Time Limits, of Chapter 4, Airworthiness Limitations, Revision 8, dated April 23, 2012, of the Cessna Model 550Maintenance Manual.
(3) Subject 4-11-00, Replacement Time Limits, of Chapter 4, Airworthiness Limitations, Revision 20, dated April 23, 2012, of the Cessna Model 560 Maintenance Manual.
(4) Subject 4-11-00, Replacement Time Limits, of Chapter 4, Airworthiness Limitations, Revision 13, dated April 23, 2012, of the Cessna Model 560XLMaintenance Manual.
(5) Subject 4-11-00, Replacement Time Limits, of Chapter 4, Airworthiness Limitations, Revision 30, dated April 23, 2012, of the Cessna Model 650 Maintenance Manual.
(6) Subject 4-11-00, Replacement Time Limits-General, of Chapter 4, Airworthiness Limitations, Revision 4, dated April 23, 2012, of the Cessna Model 500/501Maintenance Manual.
(7) Subject 4-11-00, Replacement Time Limits, of Chapter 4, Airworthiness Limitations, Revision 7, dated April 23, 2012, of the Cessna Model S550 Maintenance Manual.
In lieu of replacing the A/C compressor motor brushes as required by this AD, deactivate the A/C system as specified in paragraph (k)(1), (k)(2), or (k)(3) of this AD, as applicable.
(1) For all airplanes except Model 560XL and 650 airplanes: Pull the vapor cycle A/C circuit breaker labeled “AIR COND,” do the actions specified in paragraphs (k)(1)(i) and (k)(1)(ii) of this AD, and document deactivation of the system in the airplane logbook, referring to this AD as the reason for deactivation. While the system is deactivated, the airplane operator must remain aware of operating temperature limitations specified in the applicable airplane flight manual.
(i) Fabricate a placard that states: “A/C DISABLED” with 1/8 -inch black lettering on a white background.
(ii) Install the placard on the airplane instrument panel within 6 inches of the A/C selection switch.
(2) For Model 650 airplanes: Pull the vapor cycle A/C circuit breaker labeled “FWD EVAP FAN,” do the actions specified in paragraphs (k)(1)(i) and (k)(1)(ii) of this AD, and document deactivation of the system in the airplane logbook, referring to this AD as the reason for deactivation. While the system is deactivated, the airplane operator must remain aware of operating temperature limitations specified in the applicable airplane flight manual.
(3) For Model 560XL airplanes: Do the actions specified in paragraphs (k)(1)(i) and (k)(1)(ii) of this AD, and document deactivation of the system in the airplane logbook, referring to this AD as the reason for deactivation. While the system is deactivated, the airplane operator must remain aware of operating temperature limitations specified in the applicable airplane flight manual. Remove the fuse limiter that supplies power to the A/C compressor motor by doing the actions specified in paragraphs (k)(3)(i) through (k)(3)(viii) of this AD, and return to the airplane to service by doing the actions specified in paragraphs (k)(3)(ix) through (k)(3)(xiii) of this AD.
(i) Open the battery door.
(ii) Disconnect the main battery connector and remove external electrical power.
(iii) Tag the battery and external power receptacle with a warning tag that reads: “WARNING: Do not connect the battery connector during the maintenance in progress.”
(iv) Gain access to the J-Box through the tailcone access door.
(v) Remove the wing nuts that attach the cover to the J-Box.
(vi) Remove the J-Box cover.
(vii) Remove nuts securing compressor fuse limiter (reference designator HZ116, P/N ANL130) to the bus bar.
(viii) Remove the compressor motor fuse limiter from the terminals and retain for future reinstallation once the compressor motor brushes have been replaced.
(ix) Install fuse limiter nuts on the terminals and torque to 100 inch-pounds +/- 5 inch-pounds.
(x) Install the J-Box cover with wing nuts.
(xi) Remove the warning tag on the battery and external power receptacle.
(xii) Connect the battery and restore electrical power to the airplane.
(xiii) Close the tailcone access door.
If an operator chooses to deactivate the A/C system, as specified in paragraph (k) of this AD, and then later chooses to return the A/C system to service: Before returning the A/C system to service and removing the placard, perform the inspection specified in paragraph (h) of this AD, and do the replacements specified in paragraph (i) of this AD, at the times specified in paragraph (i) of this AD. Return the A/C system to service by doing the actions specified in paragraph (l)(1), (l)(2), or (l)(3) of this AD, as applicable.
(1) For all airplanes except Model 560XL and 650 airplanes: Push in the vapor cycle A/C circuit breaker labeled “AIR COND,” remove the placard by the A/C selection switch that states “A/C DISABLED,” and document reactivation of the system in the airplane logbook.
(2) For Model 650 airplanes: Push in the vapor cycle A/C circuit breaker labeled “FWD EVAP FAN,” remove the placard by the A/C selection switch that states “A/C DISABLED,” and document reactivation of the system in the airplane logbook.
(3) For Model 560XL airplanes: Remove the placard by the A/C selection switch that states “A/C DISABLED,” and document reactivation of the system in the airplane logbook. Re-install the fuse limiter by doing the actions specified in paragraphs (l)(3)(i) through (l)(3)(viii) of this AD, and return to the airplane to service by doing the actions specified in paragraphs (l)(3)(ix) through (l)(3)(xiii) of this AD.
(i) Open the battery door.
(ii) Disconnect the main battery connector and remove external electrical power.
(iii) Tag the battery and external power receptacle with a warning tag that reads: “WARNING: Do not connect the battery connector during the maintenance in progress.”
(iv) Gain access to the J-Box through the tailcone access door.
(v) Remove the wing nuts that attach the cover to the J-Box.
(vi) Remove the J-Box cover.
(vii) Remove the fuse limiter nuts on the bus bar terminals for the fuse limiter.
(viii) Install the compressor motor fuse limiter (reference designator HZ116, P/N ANL130).
(ix) Install fuse limiter nuts on the terminals and torque to 100 inch-pounds +/- 5 inch-pounds.
(x) Install the J-Box cover with wing nuts.
(xi) Remove the warning tag on the battery and external power receptacle.
(xii) Connect the battery and restore electrical power to the airplane.
(xiii) Close the tailcone access door.
For the first two A/C compressor motor brush replacement cycles on each airplane, send the brushes that were removed to Cessna Aircraft Company, Cessna Service Parts and Programs, 7121 Southwest Boulevard, Wichita, KS 67215. Provide the brushes and the information specified in paragraphs (m)(1) through (m)(6) of this AD within 30 days after the replacement, if the replacement was done on or after the effective date of this AD, or within 30 days after the effective date of this AD, if the replacement was done before the effective date of this AD.
(1) The model and serial number of the airplane.
(2) The part number of the motor.
(3) The part number 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.
(6) The number of motor hours currently displayed on the pallet hour meter.
As of the effective date of this AD, no person may install an A/C compressor motor having P/N 1134104-1 or P/N 1134104-5, unless the inspection specified in paragraph (h) of this AD is done before further flight, and the replacements specified in paragraph (i) of this AD are done at the times specified in paragraph (i) of this AD.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
