Commercial Fixed Wing
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 5
Training / Qualification; Communication Breakdown; Workload
ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Runway; Inflight Event / Encounter CFTT / CFIT
Air Traffic Control Issued New Clearance; Flight Crew Executed Go Around / Missed Approach
Airspace Structure; Human Factors; Procedure
I was doing OJT on Local Control. We were using the ILS RWY XX circle to RWY XY approach. The trainee cleared an Aircraft for takeoff then canceled the takeoff clearance. The Aircraft crossed the hold short line. The trainee issued the next arrival Aircraft Y a go around to fly heading 280 and maintain 018. I then issued the published missed approach. Aircraft Y then began to turn south. Aircraft Z was the next arrival and had a 60 to 70 kt overtake on Aircraft Y. I issued a 250 heading to Aircraft Y to avoid Tracon overhead traffic and to keep them away from Aircraft Z. I issued a 300 heading and 018 to Aircraft Z to avoid conflict with Aircraft Y. While I was trying to handle separation between Aircraft Y and the ZZZ1 arrival I didn't give Aircraft Z a frequency change to Tracon. Tracon called and asked me to switch Aircraft Z which I did; however Aircraft Z had flown out of the 018 MVA area and into the 020 MVA area.I would maintain better awareness of the proximity of Aircraft to the higher MVA areas and issue a climb to 020 to avoid MVA conflict.
Local controller reported failing to issue a frequency change to an aircraft resulting in aircraft entering a higher MVA.