Narrative:

While working local control south position I approved vehicle X to inspect runway 12 for a possible bird stike. Aircraft X checks in for the visual approach to runway 12. I cleared aircraft X to land runway 12. Aircraft Y checks in for runway 09. I clear aircraft Y to land runway 9 and hold short of runway 12. I instructed vehicle X to hold short of runway 9 for aircraft Z landing runway 9 with the anticipation that he would cross runway 9 after aircraft Z landed. I issued crossing instruction to aircraft a and instructed aircraft a to contact ground. Ground control asked me to have aircraft a to join taxiway quebec reference their traffic. The asde alerted that runway 12 was occupied as aircraft X was over landing threshold. I then began a transmission to aircraft X to go around and realized it was too late and then instructed vehicle X to exit the runway immediately. The memory aid was in use. While scanning the runway I did not see the vehicle on the runway. I believe I forgot about the vehicle holding short on the runway due to having aircraft exiting the runway and crossing the runways. Recommend having a cab coordinator during that time of night. Different memory aids for vehicle on the runway.

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Original NASA ASRS Text

Title: MIA Tower Controller reported aircraft landing while an airport vehicle was on the active runway.

Narrative: While working Local Control south position I approved Vehicle X to inspect runway 12 for a possible bird stike. Aircraft X checks in for the visual approach to runway 12. I cleared Aircraft X to land runway 12. Aircraft Y checks in for runway 09. I clear Aircraft Y to land runway 9 and hold short of runway 12. I instructed Vehicle X to hold short of runway 9 for Aircraft Z landing runway 9 with the anticipation that he would cross runway 9 after Aircraft Z landed. I issued crossing instruction to Aircraft A and instructed Aircraft A to contact ground. Ground control asked me to have Aircraft A to join taxiway Quebec reference their traffic. The ASDE alerted that runway 12 was occupied as Aircraft X was over landing threshold. I then began a transmission to Aircraft X to go around and realized it was too late and then instructed Vehicle X to exit the runway immediately. The memory aid was in use. While scanning the runway I did not see the vehicle on the runway. I believe I forgot about the vehicle holding short on the runway due to having aircraft exiting the runway and crossing the runways. Recommend having a cab coordinator during that time of night. Different memory aids for vehicle on the runway.

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.