Narrative:

Working the late night shift; combined tower positions. Airport operations vehicles use the call sign 'oscar;' followed by their assigned number. Oscar xy was the operations unit in charge. I received a call from oscar XXX. At the time I was in the middle of cutting the new ATIS. I answered and what follows is the exchange as I remember it. Oscar-XXX south cargo with an aircraft; request reposition to FBO X. The operations vehicle was cleared to reposition. Note this is a very routine clearance that we use many times each day. Also no runway involvement was necessary. I went back to finishing my ATIS; and updating the boards. The phone rang; and it was oscar xy (in charge). He notified me that o-xxx was actually at west cargo; and he would have him/her re-contact me for another clearance. At this time o-xxx called at 'G-1'; with an aircraft; request reposition to FBO X. Here was where I realized the vehicle and aircraft they were escorting; had crossed runway 7L; and were now holding short of runway 7R. I issued the clearance and the operation was concluded. Contributing to this confusion. Phoenix is undergoing a major runway construction project; and many vehicles are active on all surfaces of the airport. Also; all of these vehicles have the flashing yellow lights on top; as do all of the 'oscar' city vehicles. At no point was any clearance issued to cross any runway. Oscar xy called back again; asking what if anything do we want to do as far as paperwork; etc.

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Original NASA ASRS Text

Title: PHX Controller described an unauthorized airport vehicle runway crossing event; listing on going construction projects as a causal factor.

Narrative: Working the late night shift; combined Tower positions. Airport Operations vehicles use the call sign 'Oscar;' followed by their assigned number. Oscar XY was the operations unit in charge. I received a call from Oscar XXX. At the time I was in the middle of cutting the new ATIS. I answered and what follows is the exchange as I remember it. Oscar-XXX south cargo with an aircraft; request reposition to FBO X. The operations vehicle was cleared to reposition. Note this is a very routine clearance that we use many times each day. Also no runway involvement was necessary. I went back to finishing my ATIS; and updating the boards. The phone rang; and it was Oscar XY (in charge). He notified me that O-XXX was actually at west cargo; and he would have him/her re-contact me for another clearance. At this time O-XXX called at 'G-1'; with an aircraft; request reposition to FBO X. Here was where I realized the vehicle and aircraft they were escorting; had crossed Runway 7L; and were now holding short of Runway 7R. I issued the clearance and the operation was concluded. Contributing to this confusion. Phoenix is undergoing a major runway construction project; and many vehicles are active on all surfaces of the airport. Also; all of these vehicles have the flashing yellow lights on top; as do all of the 'Oscar' city vehicles. At no point was any clearance issued to cross any runway. Oscar XY called back again; asking what if anything do we want to do as far as paperwork; etc.

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.