Narrative:

I am an atcs at ZAU. Grr ATCT normally closes at XX00. When grr closes, they give us a briefing, then we assume the airspace. On this evening, they did not call at XX00. This is not that unusual, since they often stay a few mins extra if they have an aircraft on approach. I was aware that aircraft X should have landed at approximately XX00. At XX03, I attempted to call grr by landline (2 different lines). Unable to reach anyone, I assumed that the controller had forgotten to call. I notified my supervisor that I was taking over the airspace without a briefing, and cleared aircraft Y for the visual approach. Apparently, his announcement on the CTAF prompted aircraft X to call me and cancel his IFR. The pilot of aircraft X said the tower had closed while he was landing. Although, I do not believe there was any danger to anyone, this situation had potential to be worse. I was aware that aircraft X had been inbound, and had had enough time to land and cancel, even though it turned out that he had not canceled. Aircraft Y landed without incident.

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Original NASA ASRS Text

Title: ARTCC RADAR CTLR RPTS THAT HE HAS CLRED AN ACFT FOR A VISUAL APCH TO AN ARPT IN WHICH THE PREVIOUS ACFT HAD NOT YET CANCELED IFR. ALSO, THE TWR HAS CLOSED WITHOUT INTERFAC COORD ARPT STATUS AND TFC.

Narrative: I AM AN ATCS AT ZAU. GRR ATCT NORMALLY CLOSES AT XX00. WHEN GRR CLOSES, THEY GIVE US A BRIEFING, THEN WE ASSUME THE AIRSPACE. ON THIS EVENING, THEY DID NOT CALL AT XX00. THIS IS NOT THAT UNUSUAL, SINCE THEY OFTEN STAY A FEW MINS EXTRA IF THEY HAVE AN ACFT ON APCH. I WAS AWARE THAT ACFT X SHOULD HAVE LANDED AT APPROX XX00. AT XX03, I ATTEMPTED TO CALL GRR BY LANDLINE (2 DIFFERENT LINES). UNABLE TO REACH ANYONE, I ASSUMED THAT THE CTLR HAD FORGOTTEN TO CALL. I NOTIFIED MY SUPVR THAT I WAS TAKING OVER THE AIRSPACE WITHOUT A BRIEFING, AND CLRED ACFT Y FOR THE VISUAL APCH. APPARENTLY, HIS ANNOUNCEMENT ON THE CTAF PROMPTED ACFT X TO CALL ME AND CANCEL HIS IFR. THE PLT OF ACFT X SAID THE TWR HAD CLOSED WHILE HE WAS LNDG. ALTHOUGH, I DO NOT BELIEVE THERE WAS ANY DANGER TO ANYONE, THIS SIT HAD POTENTIAL TO BE WORSE. I WAS AWARE THAT ACFT X HAD BEEN INBOUND, AND HAD HAD ENOUGH TIME TO LAND AND CANCEL, EVEN THOUGH IT TURNED OUT THAT HE HAD NOT CANCELED. ACFT Y LANDED WITHOUT INCIDENT.

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.