Narrative:

Air carrier X landing runway 22R. Cleared to land; hold short of runway 27L for landing traffic. Pilot acknowledged clearance. Air carrier Y cleared to land runway 27L and told traffic landing runway 22R would hold short. Air carrier X rolling out runway 22R at midfield was instructed to turn left on taxiway C and hold short of runway 27L and remain on this frequency. I copied the readback that air carrier X would remain with me. I then turned my attention to air carrier Y landing runway 27L. Air carrier Y was now rolling out runway 27L as I began to instruct air carrier Y turn left on taxiway C and continue on taxiway B when I observed air carrier X approaching the intersection of runway 27L and taxiway C. I immediately tried to stop air carrier X's progress but the aircraft never responded.

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Original NASA ASRS Text

Title: ORD TWR CTLR EXPERIENCED OPERROR WHEN LNDG TFC ON RWY 22R CROSSED RWY 27L WITH ACFT ON LNDG ROLL.

Narrative: ACR X LNDG RWY 22R. CLRED TO LAND; HOLD SHORT OF RWY 27L FOR LNDG TFC. PLT ACKNOWLEDGED CLRNC. ACR Y CLRED TO LAND RWY 27L AND TOLD TFC LNDG RWY 22R WOULD HOLD SHORT. ACR X ROLLING OUT RWY 22R AT MIDFIELD WAS INSTRUCTED TO TURN L ON TXWY C AND HOLD SHORT OF RWY 27L AND REMAIN ON THIS FREQ. I COPIED THE READBACK THAT ACR X WOULD REMAIN WITH ME. I THEN TURNED MY ATTN TO ACR Y LNDG RWY 27L. ACR Y WAS NOW ROLLING OUT RWY 27L AS I BEGAN TO INSTRUCT ACR Y TURN L ON TXWY C AND CONTINUE ON TXWY B WHEN I OBSERVED ACR X APCHING THE INTXN OF RWY 27L AND TXWY C. I IMMEDIATELY TRIED TO STOP ACR X'S PROGRESS BUT THE ACFT NEVER RESPONDED.

Data retrieved from NASA's ASRS site as of May 2009 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.