Narrative:

I was preparing to leave the key west airport at about XA50 am. I taxied out and announced that I was about to take the runway for departure and called this on the radio. The tower answered and said they should have been contacted. Based on what someone at the FBO said, I thought the tower was closed so was planning an uncontrolled departure procedure. I apologized to the tower and was given clearance to depart. I had taxied onto the runway (after doing a 360 degree rotation on the ground with my aircraft to look for local traffic), before the tower called back to me and told me about the problem. I have never done this before and will plan in the future to look more carefully at the times of tower operation in the facility's literature.

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Original NASA ASRS Text

Title: A PVT PLT, WITH RELATIVELY HIGH TIME, ATTEMPTED TO DEPART EYW WITHOUT THE TWR'S PERMISSION.

Narrative: I WAS PREPARING TO LEAVE THE KEY WEST ARPT AT ABOUT XA50 AM. I TAXIED OUT AND ANNOUNCED THAT I WAS ABOUT TO TAKE THE RWY FOR DEP AND CALLED THIS ON THE RADIO. THE TWR ANSWERED AND SAID THEY SHOULD HAVE BEEN CONTACTED. BASED ON WHAT SOMEONE AT THE FBO SAID, I THOUGHT THE TWR WAS CLOSED SO WAS PLANNING AN UNCTLED DEP PROC. I APOLOGIZED TO THE TWR AND WAS GIVEN CLRNC TO DEPART. I HAD TAXIED ONTO THE RWY (AFTER DOING A 360 DEG ROTATION ON THE GND WITH MY ACFT TO LOOK FOR LCL TFC), BEFORE THE TWR CALLED BACK TO ME AND TOLD ME ABOUT THE PROB. I HAVE NEVER DONE THIS BEFORE AND WILL PLAN IN THE FUTURE TO LOOK MORE CAREFULLY AT THE TIMES OF TWR OP IN THE FACILITY'S LITERATURE.

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.