Narrative:

While being vectored for an ILS approach into mkl we had the field clearly in sight over 6 mi away. The WX was reported as 4000 ft overcast and 2 1/2 mi of visibility. ZME asked us to cancel as soon as possible on the ground due to traffic to follow. Without checking with me, my first officer canceled IFR at this point because he had the field in sight. I should have stopped him and informed center that we wanted to remain on our IFR flight plan, but because we so clearly had the field so far away. I let it go. Center then had us contact jackson radio for advisories. Upon contacting jackson radio we where told the field was IFR because of the 2 1/2 mi visibility report. We told them that we had the field outside the OM, and a king air taxiing and also told radio that visibility was much better than the reported 2 1/2 mi. We continued and landed, but after landing, I remembered that even though we had more than enough visibility, it was the report that mattered. 5 mins after our landing they changed the visibility to 5 mi. My first officer and I discussed the problem on the ground, and I made it clear to him not to cancel IFR without checking with me first, and never to cancel when the control zone is IFR. Contributing factors are: this was our 4TH continuous duty overnight in a row. Second I had flown with this first officer for 3 weeks, and he had done an excellent job, so I was not monitoring his actions like I should finally the inaccurate WX report caused the whole problem. If it had been updated properly, the control zone would not have been IFR.

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Original NASA ASRS Text

Title: ACR FLC CANCELS IFR FLT PLAN WHILE STILL IN IMC.

Narrative: WHILE BEING VECTORED FOR AN ILS APCH INTO MKL WE HAD THE FIELD CLRLY IN SIGHT OVER 6 MI AWAY. THE WX WAS RPTED AS 4000 FT OVCST AND 2 1/2 MI OF VISIBILITY. ZME ASKED US TO CANCEL ASAP ON THE GND DUE TO TFC TO FOLLOW. WITHOUT CHKING WITH ME, MY FO CANCELED IFR AT THIS POINT BECAUSE HE HAD THE FIELD IN SIGHT. I SHOULD HAVE STOPPED HIM AND INFORMED CTR THAT WE WANTED TO REMAIN ON OUR IFR FLT PLAN, BUT BECAUSE WE SO CLRLY HAD THE FIELD SO FAR AWAY. I LET IT GO. CTR THEN HAD US CONTACT JACKSON RADIO FOR ADVISORIES. UPON CONTACTING JACKSON RADIO WE WHERE TOLD THE FIELD WAS IFR BECAUSE OF THE 2 1/2 MI VISIBILITY RPT. WE TOLD THEM THAT WE HAD THE FIELD OUTSIDE THE OM, AND A KING AIR TAXIING AND ALSO TOLD RADIO THAT VISIBILITY WAS MUCH BETTER THAN THE RPTED 2 1/2 MI. WE CONTINUED AND LANDED, BUT AFTER LNDG, I REMEMBERED THAT EVEN THOUGH WE HAD MORE THAN ENOUGH VISIBILITY, IT WAS THE RPT THAT MATTERED. 5 MINS AFTER OUR LNDG THEY CHANGED THE VISIBILITY TO 5 MI. MY FO AND I DISCUSSED THE PROB ON THE GND, AND I MADE IT CLR TO HIM NOT TO CANCEL IFR WITHOUT CHKING WITH ME FIRST, AND NEVER TO CANCEL WHEN THE CTL ZONE IS IFR. CONTRIBUTING FACTORS ARE: THIS WAS OUR 4TH CONTINUOUS DUTY OVERNIGHT IN A ROW. SECOND I HAD FLOWN WITH THIS FO FOR 3 WKS, AND HE HAD DONE AN EXCELLENT JOB, SO I WAS NOT MONITORING HIS ACTIONS LIKE I SHOULD FINALLY THE INACCURATE WX RPT CAUSED THE WHOLE PROB. IF IT HAD BEEN UPDATED PROPERLY, THE CTL ZONE WOULD NOT HAVE BEEN IFR.

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.