Narrative:

Our flight was quite normal until the descent. We were cleared direct zzzzz for the RNAV [approach]. We were planning a short hold due to traffic. Descending through FL190 we set flaps 1 as we slowed to enter the hold. A slats locked ECAM was generated. The first officer (first officer) ran the ECAM; I took ATC and entered the hold. Quickly we realized the slats were stuck between 0 and 1; immediate concerns were the effect on landing distance; descent rate; direct law; fuel burn; rwy conditions. We went to the QRH and went first to the performance chart and the fuel burn factors. Landing was possible but less than ideal due to mountainous terrain; steep RNAV approach; runway conditions (reported swept and good; but I feared less than good [braking] with snow or ice; especially at the end of the runway; taxiways were reported poor). Fuel burn factors confirmed [a nearby alternate] was a safe option for fuel; fob (fuel on board) approximately 11;000. [Weather at the alternate] was VFR. We diverted; max alt FL190 and 220 kts. We completed the QRH procedure enroute; there was some confusion on QRH procedures requiring a reread and discussion; but time was ample to verify we were reading the QRH correctly; advised dispatch; briefed the flight attendants; and made an announcement to the passengers. After further crew discussion I decided [that since we would be dealing with] degraded flight control (direct law); unusual landing configuration; and high approach speed (hot brakes); we [would] request a 10 mile final to get stabilized before dropping the gear and being forced into direct law. Visual backed up by ILS was conducted normally; approach was hand flown to give me a few minutes of direct law flight experience before the flare. Landing was in the touchdown zone and we had selected auto brakes 1 for a gentle deceleration. We had a normal taxi to the gate. After gate arrival brakes maxed out at 350 deg.we were met by [flight] manager and went through the protocol. My first officer was a great asset and performed very well. I thought we worked well together.

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Original NASA ASRS Text

Title: A319 Captain reported diverting after experiencing a 'Slats Locked' ECAM on descent.

Narrative: Our flight was quite normal until the descent. We were cleared direct ZZZZZ for the RNAV [approach]. We were planning a short hold due to traffic. Descending through FL190 we set flaps 1 as we slowed to enter the hold. A slats locked ECAM was generated. The FO (First Officer) ran the ECAM; I took ATC and entered the hold. Quickly we realized the slats were stuck between 0 and 1; immediate concerns were the effect on landing distance; descent rate; direct law; fuel burn; rwy conditions. We went to the QRH and went first to the performance chart and the fuel burn factors. Landing was possible but less than ideal due to mountainous terrain; steep RNAV approach; runway conditions (reported swept and good; but I feared less than good [braking] with snow or ice; especially at the end of the runway; taxiways were reported poor). Fuel burn factors confirmed [a nearby alternate] was a safe option for fuel; FOB (Fuel on Board) approximately 11;000. [Weather at the alternate] was VFR. We diverted; max alt FL190 and 220 kts. We completed the QRH procedure enroute; there was some confusion on QRH procedures requiring a reread and discussion; but time was ample to verify we were reading the QRH correctly; advised Dispatch; briefed the flight attendants; and made an announcement to the passengers. After further crew discussion I decided [that since we would be dealing with] degraded flight control (direct law); unusual landing configuration; and high approach speed (hot brakes); we [would] request a 10 mile final to get stabilized before dropping the gear and being forced into direct law. Visual backed up by ILS was conducted normally; approach was hand flown to give me a few minutes of direct law flight experience before the flare. Landing was in the touchdown zone and we had selected auto brakes 1 for a gentle deceleration. We had a normal taxi to the gate. After gate arrival brakes maxed out at 350 deg.We were met by [Flight] Manager and went through the protocol. My First Officer was a great asset and performed very well. I thought we worked well together.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.