# SDR SWAA2026051197274

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: May 5, 2026
- Submitted: May 11, 2026
- Operation: Air carrier
- Aircraft: [N435WN](https://openairdocs.org/aircraft/N435WN), registered now
- Make and model: Boeing 737-7H4
- Registry model: [Boeing 737-7H4](https://openairdocs.org/model/boeing-737-7h4) (OpenAirDocs)
- Aircraft serial: 32455
- Aircraft time: 75,455 hours, 45,348 cycles
- System (JASC): [2721 · Rudder Tab Control System](https://openairdocs.org/jasc/2721)
- Part: Sensor
- Condition: Faulty
- Location: Zone 100
- Stage of operation: CR
- How discovered: O
- Nature of condition: J
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/SWAA2026051197274

## Discrepancy

AT FL400; CREW NOTED THAT YOKE WAS DISPLAYED TO RIGHT 3 UNITS; CORRECTED USING RUDDER TRIM. APPROX. 1 MINUTE LATER; CREW OBSERVED UNCOMMANDED RUDDER INPUT (SHARP YAW TO THE LEFT.) OCCURRED 3 TIMES. OCCURRED A TOTAL OF 3 TIMES IN FLIGHT.<[01] INTERROGATED #1 SMYD PER FIM 27-32 TASK 801. FOUND F/C 22-21-001 (SMYD YD FAULT) ON LEGS 12;14;21.;[02] REF TTG8Q01C1BJN- GVI OF RUDDER PCU AREA FOR CONDITION<BR> TTG8Q01C10ZL- R/R OF AILERON POS SENSOR -1<BR> TTG8Q01C1CXS- R/R OF A AND B AILERON AUTOPILOT ACTUATORS. COMPLIED SMYD BITE REF FIM 22-23 TASK 801. OKAY FOR SERVICE REF AMM 27-21-91; 22-11-33; 22-11-25;[03] INSPECTED REF [AMM 27-21-91 ALL ITEMS C/W AS REFERENCED.;[04] RII AND INSPECTED REF [AMM 27-21-91. ALL ITEMS C/W AS REFERENCED.;[05] CORRECTION TO TTG REF TO INCLUDE RUDDER PCU R/R<BR>TTG8Q01C10ZL- R/R OF AILERON POS SENSOR -1 AND R/R OF A AND B AILERON AUTO AILERON AUTOPILOT ACTUATORS<BR> TTG8Q01C1CXS- R/R OF RUDDER PCU<BR>. COMPLIED SMYD BITE REF FIM 22-23 TASK 801. OKAY FOR SERVICE REF AMM 27-21-91; 22-11-33; 22-11-25

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