Vrb tower controller reported a runway incursion. Pilot read back taxi instructions correctly; but w...

Attributes
ACN	1395497
Time
Date	201610
Local Time Of Day	1801-2400
Place
Locale Reference	VRB.Airport
State Reference	FL
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	Small Aircraft Low Wing 1 Eng Fixed Gear
Operating Under FAR Part	Part 91
Flight Phase	Taxi
Route In Use	None
Flight Plan	VFR
Aircraft 2
Make Model Name	Small Aircraft Low Wing 1 Eng Fixed Gear
Operating Under FAR Part	Part 91
Flight Phase	Initial Climb
Flight Plan	VFR
Person 1
Function	Local
Qualification	Air Traffic Control Fully Certified
Experience	Air Traffic Control Time Certified In Pos 1 (yrs) 6
Events
Anomaly	ATC Issue All Types Conflict Ground Conflict Less Severe Deviation - Procedural Clearance Ground Incursion Runway

Narrative:

I made a mistake of having aircraft X hold in position on the numbers for runway 12R. Aircraft Y landed runway 4 and exited on A1; I told aircraft Y taxi to runway 12R via a; C; hold short runway 4. He wanted to do taxi backs and he read it back correct. I cleared aircraft X for takeoff runway 12R. I scanned the final for both runway 4 and runway 12R; I then scanned taxiway a. I saw aircraft Y pass taxiway C and headed to cross runway 12R it looked like he was taxiing at a high speed. I told aircraft Y to stop; in hopes that he wouldn't cross runway 12R. Aircraft Y didn't stop and crossed runway 12R; aircraft X was airborne at approximately 200 ft and it appeared that he flew over the tail end of aircraft Y.I was wrong for putting an aircraft in position on runway 12R; I do know the procedures for line up and wait and I didn't follow them. I made a mistake and if some training for line up and wait is in store for me I deserve it; I will not take it for granted again. The traffic wasn't too busy and I was able to scan efficiently. The pilot for aircraft Y read back the instructions I gave him but didn't follow them; I should have kept a closer eye on aircraft Y.

Original NASA ASRS Text

Title: VRB Tower Controller reported a runway incursion. Pilot read back taxi instructions correctly; but went across a runway as a departing aircraft overflew the taxiing aircraft.

Narrative: I made a mistake of having Aircraft X hold in position on the numbers for Runway 12R. Aircraft Y landed Runway 4 and exited on A1; I told Aircraft Y taxi to Runway 12R via A; C; hold short Runway 4. He wanted to do taxi backs and he read it back correct. I cleared Aircraft X for takeoff Runway 12R. I scanned the final for both Runway 4 and Runway 12R; I then scanned taxiway A. I saw Aircraft Y pass taxiway C and headed to cross Runway 12R it looked like he was taxiing at a high speed. I told Aircraft Y to stop; in hopes that he wouldn't cross Runway 12R. Aircraft Y didn't stop and crossed Runway 12R; Aircraft X was airborne at approximately 200 ft and it appeared that he flew over the tail end of Aircraft Y.I was wrong for putting an aircraft in position on Runway 12R; I do know the procedures for line up and wait and I didn't follow them. I made a mistake and if some training for line up and wait is in store for me I deserve it; I will not take it for granted again. The traffic wasn't too busy and I was able to scan efficiently. The pilot for Aircraft Y read back the instructions I gave him but didn't follow them; I should have kept a closer eye on Aircraft Y.

Data retrieved from NASA's ASRS site 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.

Vrb tower controller reported a runway incursion. Pilot read back taxi instructions correctly; but went across a runway as a departing aircraft overflew the taxiing aircraft.