Tower controller described a runway incursion event when several airport vehicles were requesting ru...

Narrative:

A cessna was doing pattern work and airport maintenance was doing work throughout the airport. Ground control coordinated that airport maintenance wanted to drive runway 14L and hold short of runway 18. I approved and changed my cessna to runway 14R and cleared him for the option. The cessna asked if he could cross midfield I replied negative extend your base runway 14R; cleared for the option. Relinquished runway 14L to ground control. Then ground stated that the maintenance vehicle now wanted runway 14R. I advised him we switched the cessna to the right because of the request and to hold short of runway 14R; ground acknowledged. I believe ground was contacted by two airport vehicles with requests at the same time and because the call signs are so similar; and on frequency sound similar; one took the others permission to proceed as requested. As the aircraft was flaring over the approach end of runway 14R the controller in charge/supervisor yelled out is he on the runway; vehicle on the runway. My trainer and I were looking at the airplane and the vehicle was at the approach end of the runway but not on the runway. The confusion involved two similar sounding call signs for trucks both in the area and when ground replied. I would make sure that all vehicles that have access to the airport don't have similar sounding call signs. I also recommend better radios.

Original NASA ASRS Text

Title: Tower Controller described a runway incursion event when several airport vehicles were requesting runway clearances all with similar call signs.

Narrative: A Cessna was doing pattern work and Airport Maintenance was doing work throughout the airport. Ground Control coordinated that Airport Maintenance wanted to drive Runway 14L and hold short of Runway 18. I approved and changed my Cessna to Runway 14R and cleared him for the option. The Cessna asked if he could cross midfield I replied negative extend your base Runway 14R; cleared for the option. Relinquished Runway 14L to Ground Control. Then Ground stated that the Maintenance vehicle now wanted Runway 14R. I advised him we switched the Cessna to the right because of the request and to hold short of Runway 14R; Ground acknowledged. I believe Ground was contacted by two airport vehicles with requests at the same time and because the call signs are so similar; and on frequency sound similar; one took the others permission to proceed as requested. As the aircraft was flaring over the approach end of Runway 14R the CIC/Supervisor yelled out is he on the runway; vehicle on the runway. My Trainer and I were looking at the airplane and the vehicle was at the approach end of the runway but not on the runway. The confusion involved two similar sounding call signs for trucks both in the area and when ground replied. I would make sure that all vehicles that have access to the airport don't have similar sounding call signs. I also recommend better radios.

Data retrieved from NASA's ASRS site as of July 2013 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	1101452
Time
Date	201307
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Aircraft 1
Make Model Name	Cessna Aircraft Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	Descent
Route In Use	Visual Approach
Flight Plan	VFR
Person 1
Function	Ground Trainee
Qualification	Air Traffic Control Developmental
Person 2
Function	Instructor Local
Qualification	Air Traffic Control Fully Certified
Events
Anomaly	ATC Issue All Types Conflict Ground Conflict Less Severe Deviation - Procedural Published Material / Policy

Tower controller described a runway incursion event when several airport vehicles were requesting runway clearances all with similar call signs.