Narrative:

I was working ground control. Puerto rico port authority veh X wanted to check the VASI for runway 10. It had previously been reported OTS. The driver of the veh had a heavy accent and was hard to understand. I advised him several times to proceed to the VASI but remain clear of the runway at all times. With the resulting language problem, I should have told him to hold his position and flash his headlights for a more positive identify. As it was prpa X entered runway 10 with small aircraft Y short final. Small aircraft Y went around. The veh prpa was told to clear the runway. When prpa called the tower by landline, he said he thought I advised him to report when clear of the runway. The solution would have been ot positively identify him and have him hold his position until small aircraft Y had landed and taxied off the runway.

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Original NASA ASRS Text

Title: VEHICLE X UNAUTH RWY ENTRY CAUSED SMA Y GO AROUND.

Narrative: I WAS WORKING GND CTL. PUERTO RICO PORT AUTHORITY VEH X WANTED TO CHK THE VASI FOR RWY 10. IT HAD PREVIOUSLY BEEN RPTED OTS. THE DRIVER OF THE VEH HAD A HEAVY ACCENT AND WAS HARD TO UNDERSTAND. I ADVISED HIM SEVERAL TIMES TO PROCEED TO THE VASI BUT REMAIN CLR OF THE RWY AT ALL TIMES. WITH THE RESULTING LANGUAGE PROB, I SHOULD HAVE TOLD HIM TO HOLD HIS POS AND FLASH HIS HEADLIGHTS FOR A MORE POSITIVE IDENT. AS IT WAS PRPA X ENTERED RWY 10 WITH SMA Y SHORT FINAL. SMA Y WENT AROUND. THE VEH PRPA WAS TOLD TO CLR THE RWY. WHEN PRPA CALLED THE TWR BY LANDLINE, HE SAID HE THOUGHT I ADVISED HIM TO RPT WHEN CLR OF THE RWY. THE SOLUTION WOULD HAVE BEEN OT POSITIVELY IDENT HIM AND HAVE HIM HOLD HIS POS UNTIL SMA Y HAD LANDED AND TAXIED OFF THE RWY.

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.