Narrative:

I was cleared to taxi to runway 9R hold short of runway 9L extended centerline. I taxied west on the north side of runway 9L and held short of the runway 9L extended centerline as instructed. At that point I called ground and told them that I was ready to depart. I was then cleared by ground to cross the extended centerline of runway 9L and contact tower. I crossed the runway 9L centerline, changed to tower and continued onto runway 9R and departed runway 9R straight out, at which time I was informed of my error and told to call fcm tower on the landline when I arrived in sux. I clearly made a mistake. I, for unknown reasons to me, thought that I was cleared to depart and did so. It was not until fcm tower informed me of my mistake that I realized my wrongdoing, and started to recreate the clearance in my head. Talking to fcm tower on the phone afterward, it appears to confirm, unfortunately, that I taxied onto an active runway and departed fcm without a clearance. Considerations: 1) there were no traffic conflicts and no traffic in the immediate area. 2) it is possible that if I had received a clearance that read 'cleared to cross runway 9L centerline, hold short of runway 9R, contact tower on 118.1' I might not have made this mistake.

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Original NASA ASRS Text

Title: A BE9L PLT, TAXIING FOR TKOF AT FCM, ENTERED THE ACTIVE RWY AND TOOK OFF WITHOUT A CLRNC.

Narrative: I WAS CLRED TO TAXI TO RWY 9R HOLD SHORT OF RWY 9L EXTENDED CTRLINE. I TAXIED W ON THE N SIDE OF RWY 9L AND HELD SHORT OF THE RWY 9L EXTENDED CTRLINE AS INSTRUCTED. AT THAT POINT I CALLED GND AND TOLD THEM THAT I WAS READY TO DEPART. I WAS THEN CLRED BY GND TO CROSS THE EXTENDED CTRLINE OF RWY 9L AND CONTACT TWR. I CROSSED THE RWY 9L CTRLINE, CHANGED TO TWR AND CONTINUED ONTO RWY 9R AND DEPARTED RWY 9R STRAIGHT OUT, AT WHICH TIME I WAS INFORMED OF MY ERROR AND TOLD TO CALL FCM TWR ON THE LANDLINE WHEN I ARRIVED IN SUX. I CLRLY MADE A MISTAKE. I, FOR UNKNOWN REASONS TO ME, THOUGHT THAT I WAS CLRED TO DEPART AND DID SO. IT WAS NOT UNTIL FCM TWR INFORMED ME OF MY MISTAKE THAT I REALIZED MY WRONGDOING, AND STARTED TO RECREATE THE CLRNC IN MY HEAD. TALKING TO FCM TWR ON THE PHONE AFTERWARD, IT APPEARS TO CONFIRM, UNFORTUNATELY, THAT I TAXIED ONTO AN ACTIVE RWY AND DEPARTED FCM WITHOUT A CLRNC. CONSIDERATIONS: 1) THERE WERE NO TFC CONFLICTS AND NO TFC IN THE IMMEDIATE AREA. 2) IT IS POSSIBLE THAT IF I HAD RECEIVED A CLRNC THAT READ 'CLRED TO CROSS RWY 9L CTRLINE, HOLD SHORT OF RWY 9R, CONTACT TWR ON 118.1' I MIGHT NOT HAVE MADE THIS MISTAKE.

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.