Narrative:

I was given instructions by ground control to taxi to the active runway 15. In doing so, I had to cross runway 15 in order to get to the run-up position. I was not given 'hold short' instructions, so I proceeded to cross the runway, assuming I had received clearance to taxi all the way to the run-up position at runway 15. After completing my preflight, I contacted the tower and requested permission to depart to the south. I was given instructions to get into position. I proceeded to get onto the runway. At that point I called tower again to get a clarification if clearance to depart was given. The response from tower was the clearance to depart is given. I proceeded to takeoff as instructed, and did not hear from the tower until a change of frequency was offered as I was leaving class D airspace.

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Original NASA ASRS Text

Title: A PA28 PLT CROSSED THE ACTIVE RWY AFTER RECEIVING A CLRNC TO TAXI TO THE SAME RWY. UNAUTH RWY ENTRY.

Narrative: I WAS GIVEN INSTRUCTIONS BY GND CTL TO TAXI TO THE ACTIVE RWY 15. IN DOING SO, I HAD TO CROSS RWY 15 IN ORDER TO GET TO THE RUN-UP POS. I WAS NOT GIVEN 'HOLD SHORT' INSTRUCTIONS, SO I PROCEEDED TO CROSS THE RWY, ASSUMING I HAD RECEIVED CLRNC TO TAXI ALL THE WAY TO THE RUN-UP POS AT RWY 15. AFTER COMPLETING MY PREFLT, I CONTACTED THE TWR AND REQUESTED PERMISSION TO DEPART TO THE S. I WAS GIVEN INSTRUCTIONS TO GET INTO POS. I PROCEEDED TO GET ONTO THE RWY. AT THAT POINT I CALLED TWR AGAIN TO GET A CLARIFICATION IF CLRNC TO DEPART WAS GIVEN. THE RESPONSE FROM TWR WAS THE CLRNC TO DEPART IS GIVEN. I PROCEEDED TO TKOF AS INSTRUCTED, AND DID NOT HEAR FROM THE TWR UNTIL A CHANGE OF FREQ WAS OFFERED AS I WAS LEAVING CLASS D AIRSPACE.

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.