# SDR ASAA2017012019476

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: January 20, 2017
- Submitted: January 23, 2017
- Operation: Air carrier
- Aircraft: [N431AS](https://openairdocs.org/aircraft/N431AS), registered now
- Make and model: Boeing 737990ER
- Aircraft serial: 43255
- Aircraft time: 12,952 hours, 4,273 cycles
- System (JASC): [2230 · Auto Throttle System](https://openairdocs.org/jasc/2230)
- Part: Servo
- Part number: 305RAA1
- Part serial: AS10179
- Condition: Faulty
- Location: Autothrottle Sys
- Part time: 10,459 hours, 3,433 cycles
- Stage of operation: TO
- How discovered: O
- Nature of condition: J
- Precautionary procedure: K
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/ASAA2017012019476

## Discrepancy

AUTO THROTTLES FAILED ON TAKEOFF. WOULD RE-ENGAGE, BUT THEN CLICK OFF AS THE THROTTLE TRIES TO MOVE. GROUNDED - YES. CONFIRMED FAULT, A/T FLIGHT FAULT REVIEW SHOWS MSG 22-31688 (1) ASM2 CH-A SPD RATE MONITOR (2) ASM2 CH-A N1 RATE MONITOR, & (3) ASM2 CH-A ARM RATE MONITOR. REMOVED & REPLACED NR 2 A/T SERVO MOTOR REF AMM TASK 22-31-91, OPS CK NML. ALSO, ACCOMPLISHED FIM 22-11 TASK 802 (GP43) LRU REPLACEMENT TEST FOR A/T, OPS CK NML. THIS CLOSES MEL 22-4B. NO SPECIAL MEL PROCEDURES TO REVERSE.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.