Sat local controller described a go around event when traffic awaiting departure taxied onto the run...

Narrative:

The weather was marginal VFR. A C172 was holding short of runway 12R at kilo intersection. The C172 was given 'runway 12R at kilo; line up and wait'. I scanned my runway to make sure it was clear. When it was; I looked back down the runway; but the C172 was still holding short of runway 12R at kilo. I instructed the C172 to 'hold short of runway 12R at kilo'; which he properly acknowledged. I again scanned my runway; and when I looked back at the approach end of the runway; the C172 was taxiing across the hold short line; I immediately transmitted to the C172 to 'stop'. I instructed the C172 to make a '180 and exit the runway. The C172 exited the runway and was instructed to contact ground control on 121.2. A few minutes later; after the conversation with the flm; the C172 was holding short of runway 12R at kilo and called ready for departure. I instructed the C172 to 'hold short of runway 12R at kilo'; which he corrected acknowledged. An MD88 had been cleared to land on runway 12R and was 2-3 mile final. Again after scanning the runway to ensuring the previous arrival had cleared; I again scanned back to the approach end of the runway. The C172 had taxied onto the runway and was holding in position on runway 12R at kilo. I canceled the MD88's landing clearance and issued missed approach climb out instructions; which he appropriately acknowledged. The C172 was instructed to exit the runway and contact ground control. When the C172 exited at kilo; he was nose to nose with a king air awaiting departure. The ground controller asked for permission to utilized runway 12R to juliet intersection in order to get the C172 off of the runway. A LJ60 was behind the MD88 on final. I asked the LJ60 if he could land on runway 12L and he replied 'affirmative'. I cleared the LJ60 to land on runway 12L. Recommendation; make sure pilots understand 'line up and wait procedures'.

Original NASA ASRS Text

Title: SAT Local Controller described a go around event when traffic awaiting departure taxied onto the runway without clearance; the reporter suspecting the pilot was unfamiliar with the 'Line up and wait' phraseology.

Narrative: The weather was Marginal VFR. A C172 was holding short of Runway 12R at Kilo Intersection. The C172 was given 'Runway 12R at Kilo; Line up and wait'. I scanned my runway to make sure it was clear. When it was; I looked back down the runway; but the C172 was still holding short of Runway 12R at Kilo. I instructed the C172 to 'hold short of Runway 12R at Kilo'; which he properly acknowledged. I again scanned my runway; and when I looked back at the approach end of the runway; the C172 was taxiing across the hold short line; I immediately transmitted to the C172 to 'STOP'. I instructed the C172 to make a '180 and exit the runway. The C172 exited the runway and was instructed to contact ground control on 121.2. A few minutes later; after the conversation with the FLM; the C172 was holding short of Runway 12R at Kilo and called ready for departure. I instructed the C172 to 'hold short of Runway 12R at Kilo'; which he corrected acknowledged. An MD88 had been cleared to land on Runway 12R and was 2-3 mile final. Again after scanning the runway to ensuring the previous arrival had cleared; I again scanned back to the approach end of the runway. The C172 had taxied onto the runway and was holding in position on Runway 12R at Kilo. I canceled the MD88's landing clearance and issued missed approach climb out instructions; which he appropriately acknowledged. The C172 was instructed to exit the runway and contact Ground Control. When the C172 exited at Kilo; he was nose to nose with a King Air awaiting departure. The Ground Controller asked for permission to utilized Runway 12R to Juliet intersection in order to get the C172 off of the runway. A LJ60 was behind the MD88 on final. I asked the LJ60 if he could land on Runway 12L and he replied 'affirmative'. I cleared the LJ60 to land on Runway 12L. Recommendation; make sure pilots understand 'Line up and wait procedures'.

Data retrieved from NASA's ASRS site as of April 2012 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.

Attributes
ACN	939687
Time
Date	201103
Local Time Of Day	1201-1800
Place
Locale Reference	SAT.Airport
State Reference	TX
Environment
Flight Conditions	Marginal
Aircraft 1
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	Taxi
Route In Use	None
Flight Plan	VFR
Aircraft 2
Make Model Name	MD-88
Operating Under FAR Part	Part 121
Flight Phase	Landing
Flight Plan	IFR
Person 1
Function	Local
Events
Anomaly	Deviation - Procedural Clearance Ground Incursion Runway

Sat local controller described a go around event when traffic awaiting departure taxied onto the runway without clearance; the reporter suspecting the pilot was unfamiliar with the 'line up and wait' phraseology.