Small aircraft took off without tower clearance.

Attributes
ACN	234605
Time
Date	199302
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : hsv
State Reference	AL
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : hsv
Operator	general aviation : personal
Make Model Name	Small Aircraft
Flight Phase	climbout : takeoff ground : holding
Flight Plan	VFR
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : student
Experience	flight time last 90 days : 30 flight time total : 90 flight time type : 20
ASRS Report	234605
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : non radar
Events
Anomaly	incursion : runway
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

I had completed pretkof checklist and taxied to the hold line and stopped. I requested takeoff clearance from the tower. The following is my best recall of the events. I requested clearance to takeoff. I thought the tower responded with 'small transport on long final you are clear to go.' I looked to my left and saw the plane on final. I called the tower and said 'am I clear to takeoff.' I thought the tower said 'ok.' I taxied onto the active runway, accelerated and took off. Tower called me during climb and asked me to call them upon reaching cha. I called huntsville tower upon arriving at cha and provided requested information. End of report. I realize now I did not get proper clearance. Probable cause: I may have blocked tower's communications with me when I requested takeoff clearance the second time. I should have realized that 'ok' is not an appropriate clearance and held short. Possible corrective actions: ensure proper clearance prior to leaving the hold line, and when in doubt wait. Also I was nervous on my first solo cross country.

Original NASA ASRS Text

Title: SMA TOOK OFF WITHOUT TWR CLRNC.

Narrative: I HAD COMPLETED PRETKOF CHKLIST AND TAXIED TO THE HOLD LINE AND STOPPED. I REQUESTED TKOF CLRNC FROM THE TWR. THE FOLLOWING IS MY BEST RECALL OF THE EVENTS. I REQUESTED CLRNC TO TKOF. I THOUGHT THE TWR RESPONDED WITH 'SMT ON LONG FINAL YOU ARE CLR TO GO.' I LOOKED TO MY L AND SAW THE PLANE ON FINAL. I CALLED THE TWR AND SAID 'AM I CLR TO TKOF.' I THOUGHT THE TWR SAID 'OK.' I TAXIED ONTO THE ACTIVE RWY, ACCELERATED AND TOOK OFF. TWR CALLED ME DURING CLB AND ASKED ME TO CALL THEM UPON REACHING CHA. I CALLED HUNTSVILLE TWR UPON ARRIVING AT CHA AND PROVIDED REQUESTED INFO. END OF RPT. I REALIZE NOW I DID NOT GET PROPER CLRNC. PROBABLE CAUSE: I MAY HAVE BLOCKED TWR'S COMS WITH ME WHEN I REQUESTED TKOF CLRNC THE SECOND TIME. I SHOULD HAVE REALIZED THAT 'OK' IS NOT AN APPROPRIATE CLRNC AND HELD SHORT. POSSIBLE CORRECTIVE ACTIONS: ENSURE PROPER CLRNC PRIOR TO LEAVING THE HOLD LINE, AND WHEN IN DOUBT WAIT. ALSO I WAS NERVOUS ON MY FIRST SOLO XCOUNTRY.

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.