Narrative:

2ND flight this yr in the aircraft. Going out to maintain tailwheel currency and light aerobatics. Cleared into position and hold. While holding on runway became preoccupied with watching departing traffic, which was alternating between pitching up, and down, on departure. Eventually that traffic stabilized in a climb, and turned crosswind. With the prior departure out of the way I started my takeoff, forgetting that I had only been cleared into position and hold, not to takeoff when traffic was clear. Very accommodating controller. He cleared me for takeoff while I was on the roll. Primary cause: lack of currency, causing me to be preoccupied with aircraft control on takeoff, as opposed to really paying attention to tower clrncs.

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Original NASA ASRS Text

Title: PLT COMMENCED TKOF ROLL WITH POS AND HOLD CLRNC.

Narrative: 2ND FLT THIS YR IN THE ACFT. GOING OUT TO MAINTAIN TAILWHEEL CURRENCY AND LIGHT AEROBATICS. CLRED INTO POS AND HOLD. WHILE HOLDING ON RWY BECAME PREOCCUPIED WITH WATCHING DEPARTING TFC, WHICH WAS ALTERNATING BTWN PITCHING UP, AND DOWN, ON DEP. EVENTUALLY THAT TFC STABILIZED IN A CLB, AND TURNED XWIND. WITH THE PRIOR DEP OUT OF THE WAY I STARTED MY TKOF, FORGETTING THAT I HAD ONLY BEEN CLRED INTO POS AND HOLD, NOT TO TKOF WHEN TFC WAS CLR. VERY ACCOMMODATING CTLR. HE CLRED ME FOR TKOF WHILE I WAS ON THE ROLL. PRIMARY CAUSE: LACK OF CURRENCY, CAUSING ME TO BE PREOCCUPIED WITH ACFT CTL ON TKOF, AS OPPOSED TO REALLY PAYING ATTN TO TWR CLRNCS.

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.