Narrative:

At the time of the event; I was working local control east for a very short period of time. Aircraft abcd had been holding short of runway xxl because his gate had been unavailable. Upon receiving information that aircraft abcd's gate was now available and I had the opportunity to cross runway xxl; I instructed aircraft abcd to cross and as I was doing this I noticed that there was another aircraft abcd outbound already under ATC instruction with ground control east so I advised the aircraft abcd crossing runway xxl to remain my frequency and to hold short of K3 on K so that both aircraft wouldn't end up on the same frequency causing confusion. The next transmission I made was a takeoff clearance to to aircraft Y; who was already holding in position on runway xxl. Shortly thereafter; I realized my mistake and canceled aircraft Y's takeoff clearance but my transmission was blocked by aircraft abcd who was questioning his crossing clearance. I again canceled aircraft Y's takeoff clearance and aircraft Y read back the cancellation. Aircraft Y was then instructed to exit runway xxl at T; and aircraft abcd was given a crossing clearance. I would normally have flipped aircraft Y's strip over while holding in position and crossing down field to prevent this from happening but in my attempt to work out the duplicate identification's of the two air carrier abcd's I got distracted and did not flip the strip over. This memory jogger would have prevented this mistake from taking place

Google
 

Original NASA ASRS Text

Title: Ground Controller reported issuing a momentary takeoff clearance with traffic cleared to cross the runway; two air carriers with the identical call sign taxiing on the airport surface contributing to the event.

Narrative: At the time of the event; I was working Local Control East for a very short period of time. Aircraft ABCD had been holding short of Runway XXL because his gate had been unavailable. Upon receiving information that Aircraft ABCD's gate was now available and I had the opportunity to cross Runway XXL; I instructed Aircraft ABCD to cross and as I was doing this I noticed that there was another Aircraft ABCD outbound already under ATC instruction with Ground Control East so I advised the Aircraft ABCD crossing Runway XXL to remain my frequency and to hold short of K3 on K so that both aircraft wouldn't end up on the same frequency causing confusion. The next transmission I made was a takeoff clearance to to Aircraft Y; who was already holding in position on Runway XXL. Shortly thereafter; I realized my mistake and canceled Aircraft Y's takeoff clearance but my transmission was blocked by Aircraft ABCD who was questioning his crossing clearance. I again canceled Aircraft Y's takeoff clearance and Aircraft Y read back the cancellation. Aircraft Y was then instructed to exit Runway XXL at T; and Aircraft ABCD was given a crossing clearance. I would normally have flipped Aircraft Y's strip over while holding in position and crossing down field to prevent this from happening but in my attempt to work out the duplicate ID's of the two ACR ABCD's I got distracted and did not flip the strip over. This memory jogger would have prevented this mistake from taking place

Data retrieved from NASA's ASRS site as of April 2012 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.