Narrative:

Sfo was landing runway 28L, departing runway 1L. Runways 01R/19L and 28R/10L were closed. Mobile vehicle called requesting to inspect runway 19R. When the runway was clear, I cleared mobile vehicle to proceed on runway 19R full length. I observed the vehicle enter runway 19R at taxiway east, from between runways 19R&left. I noticed that the amass was not tracking the mobile vehicle as it proceeded down the runway. Amass was on and configured properly for the runways in use. Since amass was not tracking the vehicle, I am not sure if amass would alert if there was a conflict with the vehicle. For example, as the vehicle proceeds on runway 19R an aircraft is cleared for takeoff on runway 1L. When the aircraft begins takeoff roll on runway 1L, it is opposite direction to the vehicle on the same runway. If amass is not tracking the vehicle then it probably will not alert. The mobiles are supposed to enter the runways from a taxiway to ensure that they are tracked by amass. This mobile entered from a taxiway, but not from the center of the taxiway, they appeared to be on the south edge of the taxiway as they entered the runway. Callback conversation with reporter revealed the following information: reporter advised that because the asde/amass automation program system can track any moving vehicle, aircraft, baggage truck, tow truck, etc, a protocol had to be established to restrict amass from false alerts on the airport movement areas. Amass initiates tracking and alerts from areas closely associated with the terminal or other secondary aircraft movement areas. All other areas are inhibited from initiating an alert. Ground vehicles originating from outside the 'primary' alert areas are inhibited regardless if they transition into, then out of, a 'non inhibited/alert area.' the reporter advised that 'inhibited' vehicles cleared onto controled movement areas are tracked in the 'old way' -- physical visual indicators/mind joggers -- when amass was not installed.

Google
 

Original NASA ASRS Text

Title: SFO LCL CTLR OBSERVES ARPT GND VEHICLE NOT BEING TRACKED ON ARPT MOVEMENT AREA SAFETY SYS (AMASS) AS AN ALERT TARGET WHEN VEHICLE IS ON RWY.

Narrative: SFO WAS LNDG RWY 28L, DEPARTING RWY 1L. RWYS 01R/19L AND 28R/10L WERE CLOSED. MOBILE VEHICLE CALLED REQUESTING TO INSPECT RWY 19R. WHEN THE RWY WAS CLR, I CLRED MOBILE VEHICLE TO PROCEED ON RWY 19R FULL LENGTH. I OBSERVED THE VEHICLE ENTER RWY 19R AT TXWY E, FROM BTWN RWYS 19R&L. I NOTICED THAT THE AMASS WAS NOT TRACKING THE MOBILE VEHICLE AS IT PROCEEDED DOWN THE RWY. AMASS WAS ON AND CONFIGURED PROPERLY FOR THE RWYS IN USE. SINCE AMASS WAS NOT TRACKING THE VEHICLE, I AM NOT SURE IF AMASS WOULD ALERT IF THERE WAS A CONFLICT WITH THE VEHICLE. FOR EXAMPLE, AS THE VEHICLE PROCEEDS ON RWY 19R AN ACFT IS CLRED FOR TKOF ON RWY 1L. WHEN THE ACFT BEGINS TKOF ROLL ON RWY 1L, IT IS OPPOSITE DIRECTION TO THE VEHICLE ON THE SAME RWY. IF AMASS IS NOT TRACKING THE VEHICLE THEN IT PROBABLY WILL NOT ALERT. THE MOBILES ARE SUPPOSED TO ENTER THE RWYS FROM A TXWY TO ENSURE THAT THEY ARE TRACKED BY AMASS. THIS MOBILE ENTERED FROM A TXWY, BUT NOT FROM THE CTR OF THE TXWY, THEY APPEARED TO BE ON THE S EDGE OF THE TXWY AS THEY ENTERED THE RWY. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR ADVISED THAT BECAUSE THE ASDE/AMASS AUTOMATION PROGRAM SYS CAN TRACK ANY MOVING VEHICLE, ACFT, BAGGAGE TRUCK, TOW TRUCK, ETC, A PROTOCOL HAD TO BE ESTABLISHED TO RESTRICT AMASS FROM FALSE ALERTS ON THE ARPT MOVEMENT AREAS. AMASS INITIATES TRACKING AND ALERTS FROM AREAS CLOSELY ASSOCIATED WITH THE TERMINAL OR OTHER SECONDARY ACFT MOVEMENT AREAS. ALL OTHER AREAS ARE INHIBITED FROM INITIATING AN ALERT. GND VEHICLES ORIGINATING FROM OUTSIDE THE 'PRIMARY' ALERT AREAS ARE INHIBITED REGARDLESS IF THEY TRANSITION INTO, THEN OUT OF, A 'NON INHIBITED/ALERT AREA.' THE RPTR ADVISED THAT 'INHIBITED' VEHICLES CLRED ONTO CTLED MOVEMENT AREAS ARE TRACKED IN THE 'OLD WAY' -- PHYSICAL VISUAL INDICATORS/MIND JOGGERS -- WHEN AMASS WAS NOT INSTALLED.

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.