Narrative:

As sic and PNF on a beech king air, I obtained IFR departure clearance. After completing the runup and system checks, I called ground control and was cleared to taxi to runway 20C. It was a very short distance to the hold short point at the approach end of runway 20C. While taxiing, the controller advised that we would be #1 for departure. At this time the pilot was nearing the hold short line and had slowed almost to a complete stop. I diverted my attention inside the cockpit to verify the tower frequency and to tune it in. After doing so, I asked the pilot if he was ready. He said he was. I then looked out to the right front to check for traffic on final before calling tower. A citabria was passing directly overhead. At the same time the controller informed us that it appeared we were on the runway. Indeed we were. We were in the middle of the runway, stopped, perpendicular to the centerline, as if still holding short. I don't know if the pilot realized he had moved onto the runway or if he misunderstood the clearance. I had no doubt that we were not yet cleared onto the runway. Although my inattn to what was going on outside the aircraft lasted for only 13 seconds, it was enough to contribute to this runway incursion. Better attention on my part would have prevented it.

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Original NASA ASRS Text

Title: CAPT OF A BEECH 90 TAXIED ONTO THE ACTIVE RWY PRIOR TO BEING CLRED RESULTING IN A CITABRIA PASSING OVERHEAD FOR LNDG.

Narrative: AS SIC AND PNF ON A BEECH KING AIR, I OBTAINED IFR DEP CLRNC. AFTER COMPLETING THE RUNUP AND SYS CHKS, I CALLED GND CTL AND WAS CLRED TO TAXI TO RWY 20C. IT WAS A VERY SHORT DISTANCE TO THE HOLD SHORT POINT AT THE APCH END OF RWY 20C. WHILE TAXIING, THE CTLR ADVISED THAT WE WOULD BE #1 FOR DEP. AT THIS TIME THE PLT WAS NEARING THE HOLD SHORT LINE AND HAD SLOWED ALMOST TO A COMPLETE STOP. I DIVERTED MY ATTN INSIDE THE COCKPIT TO VERIFY THE TWR FREQ AND TO TUNE IT IN. AFTER DOING SO, I ASKED THE PLT IF HE WAS READY. HE SAID HE WAS. I THEN LOOKED OUT TO THE R FRONT TO CHK FOR TFC ON FINAL BEFORE CALLING TWR. A CITABRIA WAS PASSING DIRECTLY OVERHEAD. AT THE SAME TIME THE CTLR INFORMED US THAT IT APPEARED WE WERE ON THE RWY. INDEED WE WERE. WE WERE IN THE MIDDLE OF THE RWY, STOPPED, PERPENDICULAR TO THE CTRLINE, AS IF STILL HOLDING SHORT. I DON'T KNOW IF THE PLT REALIZED HE HAD MOVED ONTO THE RWY OR IF HE MISUNDERSTOOD THE CLRNC. I HAD NO DOUBT THAT WE WERE NOT YET CLRED ONTO THE RWY. ALTHOUGH MY INATTN TO WHAT WAS GOING ON OUTSIDE THE ACFT LASTED FOR ONLY 13 SECONDS, IT WAS ENOUGH TO CONTRIBUTE TO THIS RWY INCURSION. BETTER ATTN ON MY PART WOULD HAVE PREVENTED IT.

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.