CIRRUS AIRPLANE MAINTENANCE MANUAL

Transcription

1 SYSTEM THIRTY AUTOPILOT 1. DESCRIPTION The S-TEC System Thirty is a dual axis autopilot system that provides roll stability, heading hold, NAV/ GPS tracking capabilities, and altitude hold capabilities controlled via the roll-trim cartridge and pitch trim servo. (See Figure 1) The system components consist of an electric turn coordinator/roll computer, altitude transducer, pitch computer, and an HSI or DG for heading hold. Roll axis information is sensed by the turn coordinator gyro. Pitch axis information is sensed by the pitch axis computer. Heading information is provided to the autopilot by the HSI or DG. The operating controls for the S-TEC System Thirty Autopilot are located on the turn coordinator/roll axis computer mounted on the instrument panel. The Multi-function Control Knob is a rotary knob with an integrated push-button feature. The rotary function or the knob controls the turn command. Depressing the control knob allows the operator to highlight and scroll through the system modes. Roll Stabilization Mode is active when ST is illuminated. Wings are held level and the Turn command knob is activated for autopilot commanded turns up to 90 percent standard rate. Nav/GPS Track Mode is active when LO or HI is illuminated. The LO and HI lights indicate system gain levels. Dependent on the navigational aid used, the operator selects the appropriate gain level. Heading Hold is active when HD is illuminated. Heading Hold is facilitated by the HSI to provide heading information to the system Serials 0002 thru 2036, 2038 thru 2042: The Autopilot Disconnect Switch is integral to the 4-way trim switch on the control yoke. To disengage the autopilot depress the 4-way trim switch or depress and hold the multi-function control knob for approximately 3 seconds. Serials 2037, 2043 & subs: To disengage the autopilot depress the Autopilot Disconnect Switch or depress and hold the multi-function control knob for approximately 3 seconds. Altitude Hold is engaged by a switch on the control yoke and is active when ALT is illuminated. Flight altitude data is derived by the pressure transducer and relayed to the pitch computer to provide altitude hold. Page 1

2 2. TROUBLESHOOTING Trouble Probable Cause Remedy Unexpected flight characteristics with autopilot engaged. Moisture in static traps and/or sump. Moisture in static line. Check traps and sump for moisture. Blow out lines. Check lines for moisture. Perform System Test - Static Plumbing System (Refer to 34-10). Page 2

3 3. MAINTENANCE PRACTICES A. Turn Coordinator/Roll Computer (See Figure 2) (1) Removal - Turn Coordinator/Roll Computer (a) Set BAT 1, BAT 2, and AVIONICS master switches to OFF positions. (b) Pull TURN COORDINATOR circuit breaker. (c) Remove LH kick plate. (Refer to 25-10) (d) Disconnect instrument light connector and cable assembly from back of turn coordinator/ roll computer. (e) Remove set screw from multi-function knob and remove knob. (f) While supporting turn coordinator/roll computer, remove screws and washers securing unit to instrument panel. (g) Remove turn coordinator/roll computer from airplane. (2) Installation - Turn Coordinator/Roll Computer (a) Position turn coordinator/roll computer in instrument panel and install screws and washers. (b) Connect connector and cable assembly. (c) Install LH kick plate. (Refer to 25-10) (d) Reset TURN COORDINATOR circuit breaker. Page 3

4 B. Pitch Computer (See Figure 2) (1) Removal - Pitch Computer (a) Set BAT 1, BAT 2, and AVIONICS master switches to OFF positions. (b) Pull AUTOPILOT circuit breaker. (c) Remove MFD. (Refer to 31-60) (d) Disconnect cable from pitch computer. (e) Remove screws, washers, and nuts securing pitch computer to console. (f) Remove pitch computer from airplane. (2) Installation - Pitch Computer (a) Align pitch computer over mounting holes. Ensure data connector is pointed aft. (b) Install screws, washers, and nuts attaching pitch computer to console. (c) Connect cable assembly. (d) Install MFD. (Refer to 31-60) (e) Reset AUTOPILOT circuit breaker. Page 4

5 C. Altitude Transducer (See Figure 2) (1) Removal - Altitude Transducer (a) Set BAT 1, BAT 2, and AVIONICS master switches to OFF positions. (b) Pull AUTOPILOT circuit breaker. (c) Remove MFD. (Refer to 31-60) (d) Disconnect cable from altitude transducer. (e) Disconnect static line from altitude transducer. (f) Remove screws and washers securing altitude transducer to console rib. (g) Remove altitude transducer from airplane. (2) Installation - Altitude Transducer (a) Align altitude transducer over console rib mounting holes and secure with washers and screws. (b) Connect static line to attitude transducer. (c) Connect cable to altitude transducer. (d) Perform Pitot System Leakage Test. (Refer to 34-10) (e) Perform Static System Leakage Test. (Refer to 34-10) (f) Install MFD. (Refer to 31-60) (g) Reset AUTOPILOT circuit breaker. D. Autopilot Disconnect Switch The autopilot disconnect switch is integral to the control yoke. For maintenance practices pertinent to the control yoke, see Flight Controls. (Refer to 27-10) E. Altitude Hold Switch - Serials 0002 thru 2036, 2038 thru 2042 The autopilot hold switch is integral to the control yoke. For maintenance practices pertinent to the control yoke, see Flight Controls. (Refer to 27-10) Page 5

6 F. GPSS 429 Converter (See Figure 2) (1) Removal - GPSS 429 Converter (a) Set BAT 1, BAT 2, and AVIONICS master switches to OFF positions. (b) Disconnect battery. (Refer to 24-30) (c) Remove glareshield. (Refer to 25-10) (d) Disconnect electrical cables from GPSS 429 converter. (e) Remove screws, washers, and nuts securing GPSS 429 converter to wire loom. (2) Installation - GPSS 429 Converter (a) Install screws, washers, and nuts securing GPSS 429 converter to wire loom. (b) Connect electrical cables to GPSS 429 converter. (c) Install glareshield. (Refer to 25-10) (d) Connect battery. (Refer to 24-30) Page 6

7 G. Remote GPSS Switch (See Figure 2) (1) Removal - Remote GPSS Switch (a) Set BAT 1, BAT 2, and AVIONICS master switches to OFF positions. (b) Disconnect battery. (Refer to 24-30) (c) Remove glareshield. (Refer to 25-10) (d) Remove screws securing GPSS switch to instrument panel. (e) Disconnect electrical cable from back of GPSS switch and remove switch from airplane. (2) Installation - Remote GPSS Switch (a) Connect electrical cable to back of GPSS switch. (b) Install screws securing GPSS switch to instrument panel. (c) Install glareshield. (Refer to 25-10) (d) Connect battery. (Refer to 24-30) Page 7

8 VOR/LOC TURN COORDINATOR / ROLL COMPUTER PITCH COMPUTER PITCH TRIM SERVO ALTITUDE TRANSDUCER ROLL TRIM CARTRIDGE SR22_MM22_1551 Page 8 Figure 1 System Thirty Schematic

9 LEGEND 1. Screw 2. Washer 3. Pitch Computer 4. Cable Nut 6. Remote GPSS Switch 7. GPSS Converter 8. Adjustment Screw 9. Turn Coordinator / Roll Computer 10. Connector 11. Cable Tie 12. Static Line 13. Connector Nut 14. Nylon Insert 15. Tee 16. Altitude Transducer 11 Figure 2 System 30 w/ GPSS Installation SR22_MM22_1552A Page 9

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