Narrative:

I started engines 37 [minutes after mgw tower was scheduled to open] and immediately contacted tower for clearance. There was no response; so I waited briefly and tried a second time to establish communication. After another brief wait with no response; I tuned the ASOS to listen for remarks about hours of operation; there were none included. I then began using tower frequency as CTAF and broadcast my intentions to taxi to the active runway; and started the taxi to runway 18. During the taxi roll; I was monitoring both tower and ground frequencies to make myself available for contact on both; should the tower try to contact me. Upon reaching the runway 18; I again broadcast intentions to takeoff and departed 18. Approximately 5 minutes elapsed between startup and takeoff roll. Once airborne; I contacted ckb approach to get an enroute clearance and was instructed to return to mgw tower. I returned to tower frequency and the controller informed me that I had taxied and departed without clearance. I made it clear that I had made several attempts to establish communication without response. He never implied he made any attempts to respond; only that his supervisor would be notified.

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Original NASA ASRS Text

Title: Pilot of a light twin reports attempting to contact MGW Ground and Tower after official opening time with no success. Using CTAF procedures the reporter taxis and departs. After takeoff he is informed that the Tower was open but apparently did not hear any transmitions.

Narrative: I started engines 37 [minutes after MGW Tower was scheduled to open] and immediately contacted Tower for clearance. There was no response; so I waited briefly and tried a second time to establish communication. After another brief wait with no response; I tuned the ASOS to listen for remarks about hours of operation; there were none included. I then began using Tower frequency as CTAF and broadcast my intentions to taxi to the active runway; and started the taxi to Runway 18. During the taxi roll; I was monitoring both Tower and Ground frequencies to make myself available for contact on both; should the Tower try to contact me. Upon reaching the Runway 18; I again broadcast intentions to takeoff and departed 18. Approximately 5 minutes elapsed between startup and takeoff roll. Once airborne; I contacted CKB Approach to get an enroute clearance and was instructed to return to MGW Tower. I returned to Tower frequency and the Controller informed me that I had taxied and departed without clearance. I made it clear that I had made several attempts to establish communication without response. He never implied he made any attempts to respond; only that his Supervisor would be notified.

Data retrieved from NASA's ASRS site as of April 2012 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.