Narrative:

I was being trained on ground control. It was the beginning of a departure/arrival rush and traffic was building. I received approval for several runway xings of runway 12R at taxiway C and east. I crossed an air carrier X at taxiway C and no response. The ground control position was being split causing some frequency confusion. I then crossed an aircraft at taxiway east. I then went back to air carrier X and crossed him again reaching him on third call. I did not have any aircraft at the runway ready, but gave air carrier X clearance to cross at taxiway C. He was about 500+' from the runway on taxiway a. I then asked tower controller if air carrier on base to final 5 mi out was my traffic for crossing slot. He responded no, traffic holding in position, was I clear of runway 12R. I scanned the runway and reported clear. Air carrier Y was cleared for takeoff and downfield air carrier X turned corner and started to cross runway 12R at taxiway C. Tower controller saw crossing aircraft and cancelled takeoff clearance. Contributing factors: poor staffing levels, side by side training causing some confusion, frequency confusion, splitting positions too late, and trainers doing other positions while training. Supplemental information from acn 162049: local gave ground control clearance to cross runway 12R multiple times. The developmental crossed 3 aircraft. The third was air carrier X not quite at the runway yet. I, as the trner, got involved in answering a call on the coordinator position copying en route restrictions. The ground control developmental told local control the runway was clear. Local control cleared air carrier Y for takeoff and then had to cancel takeoff clearance when air carrier X was observed entering runway 12R.

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Original NASA ASRS Text

Title: ACR ENTERED RWY WHILE ANOTHER ACFT WAS CLEARED FOR TKOF. LESS THAN STANDARD SEPARATION. SYSTEM ERROR.

Narrative: I WAS BEING TRAINED ON GND CTL. IT WAS THE BEGINNING OF A DEP/ARR RUSH AND TFC WAS BUILDING. I RECEIVED APPROVAL FOR SEVERAL RWY XINGS OF RWY 12R AT TXWY C AND E. I CROSSED AN ACR X AT TXWY C AND NO RESPONSE. THE GND CTL POS WAS BEING SPLIT CAUSING SOME FREQ CONFUSION. I THEN CROSSED AN ACFT AT TXWY E. I THEN WENT BACK TO ACR X AND CROSSED HIM AGAIN REACHING HIM ON THIRD CALL. I DID NOT HAVE ANY ACFT AT THE RWY READY, BUT GAVE ACR X CLRNC TO CROSS AT TXWY C. HE WAS ABOUT 500+' FROM THE RWY ON TXWY A. I THEN ASKED TWR CTLR IF ACR ON BASE TO FINAL 5 MI OUT WAS MY TFC FOR XING SLOT. HE RESPONDED NO, TFC HOLDING IN POS, WAS I CLR OF RWY 12R. I SCANNED THE RWY AND RPTED CLR. ACR Y WAS CLRED FOR TKOF AND DOWNFIELD ACR X TURNED CORNER AND STARTED TO CROSS RWY 12R AT TXWY C. TWR CTLR SAW XING ACFT AND CANCELLED TKOF CLRNC. CONTRIBUTING FACTORS: POOR STAFFING LEVELS, SIDE BY SIDE TRNING CAUSING SOME CONFUSION, FREQ CONFUSION, SPLITTING POSITIONS TOO LATE, AND TRAINERS DOING OTHER POSITIONS WHILE TRNING. SUPPLEMENTAL INFO FROM ACN 162049: LCL GAVE GND CTL CLRNC TO CROSS RWY 12R MULTIPLE TIMES. THE DEVELOPMENTAL CROSSED 3 ACFT. THE THIRD WAS ACR X NOT QUITE AT THE RWY YET. I, AS THE TRNER, GOT INVOLVED IN ANSWERING A CALL ON THE COORDINATOR POS COPYING ENRTE RESTRICTIONS. THE GND CTL DEVELOPMENTAL TOLD LCL CTL THE RWY WAS CLR. LCL CTL CLRED ACR Y FOR TKOF AND THEN HAD TO CANCEL TKOF CLRNC WHEN ACR X WAS OBSERVED ENTERING RWY 12R.

Data retrieved from NASA's ASRS site as of July 2007 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.