Date: 202106
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Dusk
Aircraft: A319
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Other Go Around
Airspace: Class B ZZZ
ATC / advisory: Tower ZZZ
Aircraft component: Leading Edge Slat
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Pilot Not Flying; First Officer
Reporter qualification: Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Human factors: Training / Qualification; Troubleshooting; Workload; Situational Awareness; Communication Breakdown
Anomaly: Aircraft Equipment Problem Less Severe; Deviation - Speed All Types; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR; Inflight Event / Encounter Unstabilized Approach
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Overcame Equipment Problem; Flight Crew Requested ATC Assistance / Clarification; General Maintenance Action
Contributing factors: Aircraft; Human Factors; Procedure
Primary problem: Human Factors

Narrative: At GS intercept; 2000; on the ILS XX and as I was setting the missed approach altitude; 2;500; the outer ALT ring was in 1;000s increments. I intermittently set 3;000; reset 2;000; twisted outer ring to 100s increments; and set 2;500. In my haste twisting the outer ring; I unknowingly tugged the ALT select knob. We had just begun the descent on the GS. The engines went to climb power; destabilizing the approach immediately and the Captain called a go-around. I called the GA to Tower; and their instructions were runway heading to 2000. Since we were almost already at the GA altitude; the Captain stopped the go-around configuration at go-around flaps. We assumed a very quick return/rejoin was about to happen so he maintained gear down; flaps 2; and 170 kt.During our vectoring back to final with Approach Control; an ECAM was triggered simultaneously with autopilot disconnect cavalry audible alert; and the Captain said; 'TOGA LOCK?' He immediately accomplished a match/mash. ECAM showed AP (Autopilot)/ATHR (Autothrust) OFF; SLATS LOCKED and WINGTIP BRAKE. He maintained PF role as it was now raw data; with zero PFD (Primary Flight Display) information beyond airspeed; altitude and VSI. There were no characteristic speeds and no min/max symbols; Vls; Vmo; etc.; apart from the blue-selected speed caret. I ran the QRC; the QRH; and LAND APP procedures; as well as comms. The Captain elected to not declare an emergency; as Approach had broadcasted we were priority. We verified the approach was the appropriate one and reloaded it; a quick cursory brief about speeds; and we were cleared for the approach. One attempt was made to cycle the FDs for some guidance; to no avail. Autothrust would not engage. The Captain had to hand-fly the approach raw data. He successfully landed; we cleared the runway; and taxied to the gate.Slow is smooth and smooth is fast. In my haste to correct a simple mistake; I made a blunder. No fault go-around policy is great! There's no way of knowing if we'd have seen the slat lock if the first approach was flown to a landing. I had approximately XX hours on type.




Synopsis: A319 First Officer reported that a combination of improper adjustment of the FMC controls and a slat control failure caused additional complications during a go-around.