Narrative:

Aircraft inside marker, inbound to runway 31C, vehicle called to cross airport to terminal. Instructed vehicle to hold short of runway 31C on taxiway P. Vehicle did as instructed, entering the GS critical area for runway 31C. Aircraft went around and advised he didn't see the airport. Later he said he had a slight fluctuation in the GS at the end. Instructed vehicle to cross runway 31C and proceed to terminal. There is a service road available to the vehicle but he wanted to cross the runways.

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Original NASA ASRS Text

Title: A VEHICLE, ALLOWED BY OR IN THE ILS CRITICAL AREA BY THE ATCT LCL CTLR, CONTRIBUTES TO AN ACR MISSED APCH AT MDW, IL.

Narrative: ACFT INSIDE MARKER, INBOUND TO RWY 31C, VEHICLE CALLED TO CROSS ARPT TO TERMINAL. INSTRUCTED VEHICLE TO HOLD SHORT OF RWY 31C ON TXWY P. VEHICLE DID AS INSTRUCTED, ENTERING THE GS CRITICAL AREA FOR RWY 31C. ACFT WENT AROUND AND ADVISED HE DIDN'T SEE THE ARPT. LATER HE SAID HE HAD A SLIGHT FLUCTUATION IN THE GS AT THE END. INSTRUCTED VEHICLE TO CROSS RWY 31C AND PROCEED TO TERMINAL. THERE IS A SVC ROAD AVAILABLE TO THE VEHICLE BUT HE WANTED TO CROSS THE RWYS.

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.