Narrative:

I was PF. We landed without incident on runway 27R. On rollout, the captain began to turn left onto runway 4L/22R. I quickly checked final for runway 22R, observed an aircraft on approximately a 2 mi final and asked what I thought was tower for permission to taxi onto runway 4L. It turned out that the #1 VHF was still tuned to final approach control -- who was now a little confused. We had never switched to tower to receive and acknowledge our landing clearance. We quickly exited the runway environments and came to a stop on taxiway a where we called ground and received a clearance to taxi via taxiway a, H, and the bridge to our gate. The aircraft I had seen on final for runway 22R landed without incident some seconds after we had cleared all runways, and was rolling out as we contacted ground on taxiway a. Once off the aircraft, the captain felt it best to contact ord tower via telephone, I agreed. He told me that the supervisor jovially asked him 'didn't you see the green light signal I gave you? No problem, whatsoever.' obviously, we hadn't seen the signal.

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Original NASA ASRS Text

Title: MD80 FLT CREW LANDS WITHOUT CLRNC AND INADVERTENTLY CROSSES AN ACTIVE RWY WITHOUT CLRNC AT ORD.

Narrative: I WAS PF. WE LANDED WITHOUT INCIDENT ON RWY 27R. ON ROLLOUT, THE CAPT BEGAN TO TURN L ONTO RWY 4L/22R. I QUICKLY CHKED FINAL FOR RWY 22R, OBSERVED AN ACFT ON APPROX A 2 MI FINAL AND ASKED WHAT I THOUGHT WAS TWR FOR PERMISSION TO TAXI ONTO RWY 4L. IT TURNED OUT THAT THE #1 VHF WAS STILL TUNED TO FINAL APCH CTL -- WHO WAS NOW A LITTLE CONFUSED. WE HAD NEVER SWITCHED TO TWR TO RECEIVE AND ACKNOWLEDGE OUR LNDG CLRNC. WE QUICKLY EXITED THE RWY ENVIRONMENTS AND CAME TO A STOP ON TXWY A WHERE WE CALLED GND AND RECEIVED A CLRNC TO TAXI VIA TXWY A, H, AND THE BRIDGE TO OUR GATE. THE ACFT I HAD SEEN ON FINAL FOR RWY 22R LANDED WITHOUT INCIDENT SOME SECONDS AFTER WE HAD CLRED ALL RWYS, AND WAS ROLLING OUT AS WE CONTACTED GND ON TXWY A. ONCE OFF THE ACFT, THE CAPT FELT IT BEST TO CONTACT ORD TWR VIA TELEPHONE, I AGREED. HE TOLD ME THAT THE SUPVR JOVIALLY ASKED HIM 'DIDN'T YOU SEE THE GREEN LIGHT SIGNAL I GAVE YOU? NO PROB, WHATSOEVER.' OBVIOUSLY, WE HADN'T SEEN THE SIGNAL.

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.