Narrative:

Aircraft X checked in and was immediately given a small s-turn for spacing between him and the preceding aircraft to be able to depart aircraft Y. Everything appeared as though it would work. Aircraft Y was given an immediate takeoff clearance. As aircraft X was in the flare; he initiated a go-around. Runway separation was close to 6000 feet and airborne but no action was taken by me because it seemed safer at that point to let the aircraft land rather than executing a go-around. It was simply a judgement call. Aircraft X was given a climb to 4000 feet and a 150 heading. I should have given aircraft X a larger south turn or not tried to hit the gap with aircraft X and aircraft Y.

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Original NASA ASRS Text

Title: SAT Tower Controller reported an aircraft on short final initiated a go-around due to departing traffic from the same runway.

Narrative: Aircraft X checked in and was immediately given a small S-turn for spacing between him and the preceding aircraft to be able to depart Aircraft Y. Everything appeared as though it would work. Aircraft Y was given an immediate takeoff clearance. As Aircraft X was in the flare; he initiated a go-around. Runway separation was close to 6000 feet and airborne but no action was taken by me because it seemed safer at that point to let the aircraft land rather than executing a go-around. It was simply a judgement call. Aircraft X was given a climb to 4000 feet and a 150 heading. I should have given Aircraft X a larger S turn or not tried to hit the gap with Aircraft X and Aircraft Y.

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.