Narrative:

Aircraft X was a maintenance aircraft under tow repositioning from the west side of the airport to the east side. Aircraft X was instructed to proceed via taxiways dd; G to hold short of RWY4. A portion of taxiway a was closed for aircraft that were parked on the taxiway overnight. On this flow outbound departures typically taxi via a; east and B but with taxiway a closed between east and G they had to taxi via a; G and B. My plan was to have aircraft X hold short of RWY4 for a few minutes until a couple outbound aircraft cleared taxiway G and taxiway B. After reviewing the audio; aircraft Y had called for outbound taxi. Mistakenly I called them aircraft Y maintenance and gave them clearance to taxi via north; a and hold short of M. Aircraft X maintenance took the clearance and read it back. At that point aircraft X crossed the active departure runway (RWY4) and went onto taxiway B. Even though I missed the read back; at no point did I instruct any aircraft to cross a runway. I am perplexed as to why aircraft X did not question the clearance. They were holding short of RWY4 at G. The clearance they took was taxi north; a hold short of M and there were not crossing instructions in the clearance. There is no possible way to get to taxiway north from where they were. I got busy with other duties and caught the crossing just as they cleared. Local control had cleared aircraft Z for takeoff as aircraft X was crossing. It appears that aircraft Z delayed their takeoff roll and verified with local control that they were cleared for takeoff. I don't believe it is good practice to use an actual callsign to tow/re-position aircraft. Aircraft X is an actual flight in the NAS. [Other companies] use a combination of letters and numbers. These maintenance aircraft are typically driven by ramp workers and not pilots. Giving these guys similar sounding callsigns is not a good idea and will probably lead to more of these incidents.

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Original NASA ASRS Text

Title: LGA Tower Controllers reported a tug driver towing an aircraft took another aircraft's instructions and taxied across a runway while a departure was cleared to takeoff.

Narrative: Aircraft X was a maintenance aircraft under tow repositioning from the west side of the airport to the east side. Aircraft X was instructed to proceed via taxiways DD; G to hold short of RWY4. A portion of taxiway A was closed for aircraft that were parked on the taxiway overnight. On this flow outbound departures typically taxi via A; E and B but with taxiway A closed between E and G they had to taxi via A; G and B. My plan was to have Aircraft X hold short of RWY4 for a few minutes until a couple outbound aircraft cleared taxiway G and taxiway B. After reviewing the audio; Aircraft Y had called for outbound taxi. Mistakenly I called them Aircraft Y maintenance and gave them clearance to taxi via N; A and hold short of M. Aircraft X maintenance took the clearance and read it back. At that point Aircraft X crossed the active departure runway (RWY4) and went onto taxiway B. Even though I missed the read back; at no point did I instruct any aircraft to cross a runway. I am perplexed as to why Aircraft X did not question the clearance. They were holding short of RWY4 at G. The clearance they took was taxi N; A hold short of M and there were not crossing instructions in the clearance. There is no possible way to get to taxiway N from where they were. I got busy with other duties and caught the crossing just as they cleared. Local Control had cleared Aircraft Z for takeoff as Aircraft X was crossing. It appears that Aircraft Z delayed their takeoff roll and verified with local control that they were cleared for takeoff. I don't believe it is good practice to use an actual callsign to tow/re-position aircraft. Aircraft X is an actual flight in the NAS. [Other companies] use a combination of letters and numbers. These maintenance aircraft are typically driven by ramp workers and not pilots. Giving these guys similar sounding callsigns is not a good idea and will probably lead to more of these incidents.

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.