Narrative:

I was running up our aircraft for an administrative reposition flight to a nearby heliport. Just prior to calling to request departure; a flight request came in for us over our radio. Distracted by the change (several radio calls with our dispatch; destination change; flight approval change; etc.); I taxied to our normal take-off taxiway and departed the airport without calling the control tower. There was no immediate traffic in the area at the time. The radio was set to the appropriate tower frequency; but quiet. Approximately 30 seconds after takeoff; realizing what I had done; I called tower to let them know what I had done. To my knowledge; my actions caused no immediate effects on other traffic.

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Original NASA ASRS Text

Title: Distracted by ancillary events while preparing for a flight; the pilot of a helicopter took off without contact with the tower.

Narrative: I was running up our aircraft for an administrative reposition flight to a nearby heliport. Just prior to calling to request departure; a flight request came in for us over our radio. Distracted by the change (several radio calls with our Dispatch; destination change; flight approval change; etc.); I taxied to our normal take-off taxiway and departed the airport without calling the Control Tower. There was no immediate traffic in the area at the time. The radio was set to the appropriate tower frequency; but quiet. Approximately 30 seconds after takeoff; realizing what I had done; I called Tower to let them know what I had done. To my knowledge; my actions caused no immediate effects on other traffic.

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.