Date: 202107
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Aircraft: Commercial Fixed Wing
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Cargo / Freight / Delivery
Flight phase: Landing
ATC / advisory: Tower ZZZ
Second aircraft: Bombardier/Canadair Undifferentiated or Other Model
Reporter organization: Government
Reporter function: Other / Unknown
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Workload; Time Pressure; Situational Awareness; Distraction; Human-Machine Interface
Second reporter function: Local
Anomaly: ATC Issue All Types; Conflict Ground Conflict; Critical; Conflict Ground Conflict; Less Severe; Deviation / Discrepancy - Procedural Other / Unknown; Ground Incursion Runway
Detector: Automation Air Traffic Control; Person Air Traffic Control
When detected: In-flight; Taxi
Result: Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Executed Go Around / Missed Approach; General Flight Cancelled / Delayed
Contributing factors: Airspace Structure; Company Policy; Human Factors; Procedure; Staffing
Primary problem: Human Factors

Narrative: Aircraft X had landed [Runway] XXR and stopped on the runway to question the exiting instructions. This delay in exiting caused the next [Runway] XXR arrival to go around. Then; an airport vehicle requested permission to inspect the runway because there's some local airport procedure to sweep the runway behind a [type aircraft]. There was a full sequence of arrivals to [Runway] XXR and [Runway] XY. Then; while the Local Controller was sorting out the Aircraft X arrival; the succeeding go-around; and the airport vehicle; Aircraft Y ([Runway] XXR) and the Aircraft Z ([Runway] XY) tied at the intersection. ASDE-X (Airport Surface Detection Equipment) alarmed; Local Controller issued a late go-around.Actual time on position may not have been a factor; rather the lack of staffing to open other positions and reduce the Local Controller's workload. There were only two of us in the tower at the time; simply because no one else was available. We had asked; and been told that we would be getting more people at XA:30z. Positions in the TRACON were also combined; and despite the fact that management had kept 3 tower-certified controllers down [in the TRACON] to 'get time'; one controller was working both the runways Arrival position; and vectoring the final to Runway [Runway] XY having to sequence in with the intersecting [Runway] XXR arrivals. The search for more controllers is on-going. What else can one do; when asking for more staffing; and being told to just wait?


Second narrative: I was working Local Controls combined. I had Aircraft X land Runway XXR. I told the aircraft to exit the runway at taxiway. An airport vehicle asked to check the runway behind the Aircraft X as per our SOP (Standard Operating Procedure). Aircraft X then stopped at taxiway on the runway an asked if I was sure I wanted him to clear there as he is a [type aircraft]. I said affirmative. It was then too close for the next arrival to land safely so I sent him around. I then got the airport vehicle on to the runway but had to have him exit early as more arrivals were too close. It was then that the ASDE-X (Airport Surface Detection Equipment) alarmed informing me that the next [Runway] XXR arrival and [Runway] XY arrival were in conflict. I sent the [Runway] XXR arrival; Aircraft Y; around. Aircraft Y was about to touch down when he executed the go around. I had become distracted by the situation with Aircraft X and vehicle. By the time I was made aware of the tie between the [Runway] XY arrival and [Runway] XXR arrival the ASDE-X had alarmed. I would give more space behind Aircraft X to do the runway sweep and maybe have local controls split during the push.


Synopsis: Tower Controllers reported a landing aircraft on short final was sent around when the ASDE-X alarm alerted the Local Controller to conflicting traffic landing on an intersecting runway. The Local Controller working both Local positions combined due to a lack of staffing was distracted by a previous arrival stopping on the runway causing the Controller to have to send a subsequent arrival around.