# SDR CA190625013

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: June 19, 2019
- Submitted: August 17, 2020
- Operation: General aviation
- Make and model: Airbus BD-500-1A11
- Registry model: [Airbus BD-500-1A11](https://openairdocs.org/model/airbus-canada-lp-bd-500-1a11) (OpenAirDocs)
- System (JASC): [2230 · Auto Throttle System](https://openairdocs.org/jasc/2230)
- Part: Autothrottle Sys
- Condition: Malfunctioned
- Stage of operation: NR
- How discovered: 9
- Nature of condition: O
- Precautionary procedure: O
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/CA190625013

## Discrepancy

(CAN)  AS PER TC AND AIRBUS CANADA, A SDR MUST BE CREATED FOR EACH FMS EVENT`  SER - AUTO-THROTTLE MODE MISBEHAVIOR  DURING ACCELERATION SEGMENT AFTER TAKEOFF THE A/THR MODE CHANGED SEVERAL TIMES FROM CLB-1 TO GA THRUST.  ACTUAL N1 INCREASE/DECREASE NOTICED.  I LEFT THE AUTO-THROTTLE INTENTIONALLY ENGAGED, BUT OPENED THE THRUST MENU ON THE FMS. I NOTICED THE SWITCHING THERE AS WELL.  CHANGING FROM MANAGED THRUST TO MANUAL THRUST SETTING (CYAN) STOPPED THE SWITCHING BETWEEN THE DIFFERENT RATINGS.   ADDITIONALLY I NOTICED THAT THE RATING SWITCHING TOOK PLACE EVERY TIME THE `WXR PWS FAIL` NUISANCE ADVISORY WAS DISPLAYED. (ADVISORY SHOWN = GA THRUST) - (ADVISORY GONE - CLB-1). THE HMU WAS DEGRADED AS WELL (CONSIDERED NUISANCE).   THE LAST 2 ITEMS MAY OR MAY NOT BE CORRELATED TO THE ATHR INCIDENT - BUT TO US IT SEEMED LIKE AT LEAST THE WXR FAIL ADVISORY WAS CONNECTED. (TC# 20190625013)

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