Narrative:

The situation that occurred was a runway incursion that I believe resulted from complacency. Initially, we were to take off from runway 5, and run-up at the tees. I taxied away from the run-up area without a further taxi clearance, which normally you do not need, but in this situation, it is needed. Next, the departure runway was changed from runway 5 to runway 31. Normally, you are to taxi across runway 31 to get to runway 5, so I taxied onto runway 31 with ground control, without talking to tower. I got complacent, and didn't think about the situation and how it was changing. What can be done to prevent this from future occurrence is to always remain vigilant, and if something doesn't seem right, it probably isn't. Stop and ask ATC. I thought something wasn't quite right, but I continued on anyway in order to get the flight complete.

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Original NASA ASRS Text

Title: RWY INCURSION BY A LOW TIME C172 PVT PLT AT BTL, MI.

Narrative: THE SIT THAT OCCURRED WAS A RWY INCURSION THAT I BELIEVE RESULTED FROM COMPLACENCY. INITIALLY, WE WERE TO TAKE OFF FROM RWY 5, AND RUN-UP AT THE TEES. I TAXIED AWAY FROM THE RUN-UP AREA WITHOUT A FURTHER TAXI CLRNC, WHICH NORMALLY YOU DO NOT NEED, BUT IN THIS SIT, IT IS NEEDED. NEXT, THE DEP RWY WAS CHANGED FROM RWY 5 TO RWY 31. NORMALLY, YOU ARE TO TAXI ACROSS RWY 31 TO GET TO RWY 5, SO I TAXIED ONTO RWY 31 WITH GND CTL, WITHOUT TALKING TO TWR. I GOT COMPLACENT, AND DIDN'T THINK ABOUT THE SIT AND HOW IT WAS CHANGING. WHAT CAN BE DONE TO PREVENT THIS FROM FUTURE OCCURRENCE IS TO ALWAYS REMAIN VIGILANT, AND IF SOMETHING DOESN'T SEEM RIGHT, IT PROBABLY ISN'T. STOP AND ASK ATC. I THOUGHT SOMETHING WASN'T QUITE RIGHT, BUT I CONTINUED ON ANYWAY IN ORDER TO GET THE FLT COMPLETE.

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.