Narrative:

I was cleared to taxi to runway 4. 1/2 way out, ground controller asked me if I could accept runway 4. I acknowledged yes. Upon reaching the end of runway, I notified tower that I was ready for takeoff. Tower advised me to hold. I acknowledged and read back the hold short instructions. Approximately 10-15 seconds later, tower advised 'aircraft X is cleared for wry 4' (best I can recall). I acknowledged 'aircraft X cleared for takeoff, runway 4.' upon rollout, I saw a fire truck just clearing the end off the runway crossing left to right. As I reached 200-300 ft altitude, I heard the controller say 'aircraft X is cleared for...,' 'aircraft X you just took off without a takeoff clearance.' in my opinion I think this controller was inexperienced. Asking me if could accept the short runway after I was cleared to taxi to it was odd. (Same ground and tower controller working both position.) he may have cleared someone else to take off on another wy and used my n-number instead. Although I do recall him specifically clearing me to take off on runway 4. Or maybe he intended to clear me to position and hold on runway 4. Either that or I took someone else's takeoff clearance. An intersecting runway was in use at the time.

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Original NASA ASRS Text

Title: C320 PLT INTERPS MLB CTLR CLRNC AS TKOF AUTH, OBSERVING A VEHICLE XING THE RWY AT APPROX 250 FT ON CLBOUT.

Narrative: I WAS CLRED TO TAXI TO RWY 4. 1/2 WAY OUT, GND CTLR ASKED ME IF I COULD ACCEPT RWY 4. I ACKNOWLEDGED YES. UPON REACHING THE END OF RWY, I NOTIFIED TWR THAT I WAS READY FOR TKOF. TWR ADVISED ME TO HOLD. I ACKNOWLEDGED AND READ BACK THE HOLD SHORT INSTRUCTIONS. APPROX 10-15 SECONDS LATER, TWR ADVISED 'ACFT X IS CLRED FOR WRY 4' (BEST I CAN RECALL). I ACKNOWLEDGED 'ACFT X CLRED FOR TKOF, RWY 4.' UPON ROLLOUT, I SAW A FIRE TRUCK JUST CLRING THE END OFF THE RWY XING L TO R. AS I REACHED 200-300 FT ALT, I HEARD THE CTLR SAY 'ACFT X IS CLRED FOR...,' 'ACFT X YOU JUST TOOK OFF WITHOUT A TKOF CLRNC.' IN MY OPINION I THINK THIS CTLR WAS INEXPERIENCED. ASKING ME IF COULD ACCEPT THE SHORT RWY AFTER I WAS CLRED TO TAXI TO IT WAS ODD. (SAME GND AND TWR CTLR WORKING BOTH POS.) HE MAY HAVE CLRED SOMEONE ELSE TO TAKE OFF ON ANOTHER WY AND USED MY N-NUMBER INSTEAD. ALTHOUGH I DO RECALL HIM SPECIFICALLY CLRING ME TO TAKE OFF ON RWY 4. OR MAYBE HE INTENDED TO CLR ME TO POS AND HOLD ON RWY 4. EITHER THAT OR I TOOK SOMEONE ELSE'S TKOF CLRNC. AN INTERSECTING RWY WAS IN USE AT THE TIME.

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.