Narrative:

Departed from ism unaware that temporary control tower was still in use. Called intentions on CTAF frequency, when departing. No conflict or other traffic seen. Departed to southwest. Florida state airfare was conducted at kissimmee airport (ism), fl, over wkend, sat and sun. I flew my airplane into ism on fri, but due to WX, I had to return on mon to pick it up for return to home base. I did not realize temporary ATCT was still in operation and did not receive clearance to depart. Will check NOTAMS more closely for operation dates of temporary ATCT.

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Original NASA ASRS Text

Title: TAXI AND TKOF WITHOUT CONTACTING TEMPORARY CTL TWR.

Narrative: DEPARTED FROM ISM UNAWARE THAT TEMPORARY CTL TWR WAS STILL IN USE. CALLED INTENTIONS ON CTAF FREQ, WHEN DEPARTING. NO CONFLICT OR OTHER TFC SEEN. DEPARTED TO SW. FLORIDA STATE AIRFARE WAS CONDUCTED AT KISSIMMEE ARPT (ISM), FL, OVER WKEND, SAT AND SUN. I FLEW MY AIRPLANE INTO ISM ON FRI, BUT DUE TO WX, I HAD TO RETURN ON MON TO PICK IT UP FOR RETURN TO HOME BASE. I DID NOT REALIZE TEMPORARY ATCT WAS STILL IN OP AND DID NOT RECEIVE CLRNC TO DEPART. WILL CHK NOTAMS MORE CLOSELY FOR OP DATES OF TEMPORARY ATCT.

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.