Narrative:

I was the ground controller at mgw tower. Small aircraft X from the FBO called for taxi. I assigned runway 23 for takeoff (as the winds were 240 at 8) with a 'taxi to' clearance. This route crosses runway 18 at approximately midfield (coordination was completed with local control for the runway crossing). Approach control called and requested to vector an atx Y 'in-close' to the airport in hopes of a visual approach (visibility approximately 6 mi in haze) (flight data was combined with my position). Approximately 2 mins later, the atx Y calls tower on the radio and requests a 360 degree turn in order to lose altitude, as he was approximately 2000 AGL 1 mi north of the airport. I then called approach control to advise them of the 360 degree turn. Upon completion of the call, I then watched atx Y land and start rolling out. My first indication something was wrong was when the developmental on local control started yelling 'stop! Stop!' I then looked in the direction he was looking and saw small aircraft X crossing the yellow hold short lines. I immediately ordered small aircraft X to just plain 'stop!' the pilot of small aircraft X executed a perfect 180 degree turn on a dime, never crossing the runway edge lines. Atx Y rolled to a stop prior to the intersection. The pilots of atx Y later told us that they saw small aircraft X and judged that he was not going to hold short of their runway and that they used a little extra braking to stop their rollout. Causes? Attention diversion -- small aircraft X was my only plane and atx Y was local's only plane. The 360 degree turn required a coordination call that made me completely forget about small aircraft X. Personally, I will never issue a 'taxi to' runway 23 from this point on. Small aircraft X took a long time to start his taxi from the time he requested taxi, and I believe that 'helped' me to forget about him. From now on, my words will be 'runway 23, taxi, hold short of runway 18.'

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Original NASA ASRS Text

Title: RWY INCURSION SMA X CROSSED HOLD LINE WITH ATX Y LNDG. MULTIPLE RWY OP INTERSECTING RWYS. SYS ERROR.

Narrative: I WAS THE GND CTLR AT MGW TWR. SMA X FROM THE FBO CALLED FOR TAXI. I ASSIGNED RWY 23 FOR TKOF (AS THE WINDS WERE 240 AT 8) WITH A 'TAXI TO' CLRNC. THIS RTE CROSSES RWY 18 AT APPROX MIDFIELD (COORD WAS COMPLETED WITH LCL CTL FOR THE RWY XING). APCH CTL CALLED AND REQUESTED TO VECTOR AN ATX Y 'IN-CLOSE' TO THE ARPT IN HOPES OF A VISUAL APCH (VISIBILITY APPROX 6 MI IN HAZE) (FLT DATA WAS COMBINED WITH MY POS). APPROX 2 MINS LATER, THE ATX Y CALLS TWR ON THE RADIO AND REQUESTS A 360 DEG TURN IN ORDER TO LOSE ALT, AS HE WAS APPROX 2000 AGL 1 MI N OF THE ARPT. I THEN CALLED APCH CTL TO ADVISE THEM OF THE 360 DEG TURN. UPON COMPLETION OF THE CALL, I THEN WATCHED ATX Y LAND AND START ROLLING OUT. MY FIRST INDICATION SOMETHING WAS WRONG WAS WHEN THE DEVELOPMENTAL ON LCL CTL STARTED YELLING 'STOP! STOP!' I THEN LOOKED IN THE DIRECTION HE WAS LOOKING AND SAW SMA X XING THE YELLOW HOLD SHORT LINES. I IMMEDIATELY ORDERED SMA X TO JUST PLAIN 'STOP!' THE PLT OF SMA X EXECUTED A PERFECT 180 DEG TURN ON A DIME, NEVER XING THE RWY EDGE LINES. ATX Y ROLLED TO A STOP PRIOR TO THE INTXN. THE PLTS OF ATX Y LATER TOLD US THAT THEY SAW SMA X AND JUDGED THAT HE WAS NOT GOING TO HOLD SHORT OF THEIR RWY AND THAT THEY USED A LITTLE EXTRA BRAKING TO STOP THEIR ROLLOUT. CAUSES? ATTN DIVERSION -- SMA X WAS MY ONLY PLANE AND ATX Y WAS LCL'S ONLY PLANE. THE 360 DEG TURN REQUIRED A COORD CALL THAT MADE ME COMPLETELY FORGET ABOUT SMA X. PERSONALLY, I WILL NEVER ISSUE A 'TAXI TO' RWY 23 FROM THIS POINT ON. SMA X TOOK A LONG TIME TO START HIS TAXI FROM THE TIME HE REQUESTED TAXI, AND I BELIEVE THAT 'HELPED' ME TO FORGET ABOUT HIM. FROM NOW ON, MY WORDS WILL BE 'RWY 23, TAXI, HOLD SHORT OF RWY 18.'

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.