Takeoff without clearance.

Attributes
ACN	129906
Time
Date	198911
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz
State Reference	US
Altitude	agl bound lower : 0 agl bound upper : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air taxi
Make Model Name	Helicopter
Flight Phase	climbout : takeoff ground other : taxi
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial pilot : atp pilot : cfi
Experience	flight time last 90 days : 78 flight time total : 4440 flight time type : 1439
ASRS Report	129906
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	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Had completed run-up checks on flight center ramp. Got ATIS information and called tower requesting taxi (hover) to taxiway alpha, with takeoff into the wind, right turn out wbound. Tower came back with clearance to taxiway alpha, and with what I thought was heading southeast, right turn-out. I taxied to alpha and began takeoff and right turn-out. Tower called me and said he had not given me clearance to take off! I told him I was sorry and thought he had given me clearance to taxi to alpha and takeoff with right turn-out. He let me proceed with my original request. Often the tower will clear us from our spot on the ramp to taxi and takeoff with our direction of flight all approved from the ramp, especially when we are operating on a EMS mission, as we were in this case. I must not have listened closely enough to his (tower's) original taxi clearance to note that my limit was to taxiway alpha facing southeast.

Original NASA ASRS Text

Title: TKOF WITHOUT CLRNC.

Narrative: HAD COMPLETED RUN-UP CHKS ON FLT CENTER RAMP. GOT ATIS INFO AND CALLED TWR REQUESTING TAXI (HOVER) TO TXWY ALPHA, WITH TKOF INTO THE WIND, RIGHT TURN OUT WBOUND. TWR CAME BACK WITH CLRNC TO TXWY ALPHA, AND WITH WHAT I THOUGHT WAS HDG SE, RIGHT TURN-OUT. I TAXIED TO ALPHA AND BEGAN TKOF AND RIGHT TURN-OUT. TWR CALLED ME AND SAID HE HAD NOT GIVEN ME CLRNC TO TAKE OFF! I TOLD HIM I WAS SORRY AND THOUGHT HE HAD GIVEN ME CLRNC TO TAXI TO ALPHA AND TKOF WITH RIGHT TURN-OUT. HE LET ME PROCEED WITH MY ORIGINAL REQUEST. OFTEN THE TWR WILL CLR US FROM OUR SPOT ON THE RAMP TO TAXI AND TKOF WITH OUR DIRECTION OF FLT ALL APPROVED FROM THE RAMP, ESPECIALLY WHEN WE ARE OPERATING ON A EMS MISSION, AS WE WERE IN THIS CASE. I MUST NOT HAVE LISTENED CLOSELY ENOUGH TO HIS (TWR'S) ORIGINAL TAXI CLRNC TO NOTE THAT MY LIMIT WAS TO TXWY ALPHA FACING SE.

Data retrieved from NASA's ASRS site as of August 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.