Narrative:

The C182 was told to taxi to runway 23L. He taxied past the hold short line and onto the runway. As our tower is less than 1/2 the height it should be, per FAA standards, I was unable to see the aircraft was going on the runway until he had already entered it. The PC12 was 1/4 mi final and had to be moved to runway 23.

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Original NASA ASRS Text

Title: ATCT GND CTLR AT TYS CLAIMS CTL TWR IS NOT HIGH ENOUGH TO SEE GND TFC INCURSIONS.

Narrative: THE C182 WAS TOLD TO TAXI TO RWY 23L. HE TAXIED PAST THE HOLD SHORT LINE AND ONTO THE RWY. AS OUR TWR IS LESS THAN 1/2 THE HEIGHT IT SHOULD BE, PER FAA STANDARDS, I WAS UNABLE TO SEE THE ACFT WAS GOING ON THE RWY UNTIL HE HAD ALREADY ENTERED IT. THE PC12 WAS 1/4 MI FINAL AND HAD TO BE MOVED TO RWY 23.

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.