Narrative:

I entered the active runway for departure west/O contacting the tower. When I realized the error I stopped on the active and called the tower, announcing that I was ready to depart. The tower cleared me for takeoff. This incident is a human performance failure perhaps caused by cockpit confusion just prior to departure. At my request, ground control had altered my departure instruction. I had changed frequencys to request this route change and I believe this unusual procedure upset my normal pattern.

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Original NASA ASRS Text

Title: SMA TAXIES INTO POSITION ON ACTIVE RWY WITHOUT CLRNC.

Narrative: I ENTERED THE ACTIVE RWY FOR DEP W/O CONTACTING THE TWR. WHEN I REALIZED THE ERROR I STOPPED ON THE ACTIVE AND CALLED THE TWR, ANNOUNCING THAT I WAS READY TO DEPART. THE TWR CLRED ME FOR TKOF. THIS INCIDENT IS A HUMAN PERFORMANCE FAILURE PERHAPS CAUSED BY COCKPIT CONFUSION JUST PRIOR TO DEP. AT MY REQUEST, GND CTL HAD ALTERED MY DEP INSTRUCTION. I HAD CHANGED FREQS TO REQUEST THIS RTE CHANGE AND I BELIEVE THIS UNUSUAL PROC UPSET MY NORMAL PATTERN.

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.