Narrative:

DH8C was sent around after an approach to runway 35 due to a safety alert issued by the amass concerning that aircraft and another one landing runway 27R. Alert was predicated that 2 aircraft landing on converging runways would be in conflict. Collision was not imminent. In fact; the DH8C could have landed legally; as the arrival for runway 27R was through the intersection before the DH8C was across the landing threshold for runway 35. This alert caused me to send the DH8C around at very short notice; possibly creating a situational distraction from other pressing duties at the time. In retrospect; the go around was not needed; but created by an alert tolerance setting within the amass system.

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Original NASA ASRS Text

Title: PHL CTLR DESCRIBED REQUIRED ISSUANCE OF GAR FOR DH8 LNDG RWY 35 WHEN LEGAL SEPARATION EXISTED BUT AMASS ALERT ACTIVATED FOR RWY 27R ARR.

Narrative: DH8C WAS SENT AROUND AFTER AN APCH TO RWY 35 DUE TO A SAFETY ALERT ISSUED BY THE AMASS CONCERNING THAT ACFT AND ANOTHER ONE LNDG RWY 27R. ALERT WAS PREDICATED THAT 2 ACFT LNDG ON CONVERGING RWYS WOULD BE IN CONFLICT. COLLISION WAS NOT IMMINENT. IN FACT; THE DH8C COULD HAVE LANDED LEGALLY; AS THE ARR FOR RWY 27R WAS THROUGH THE INTXN BEFORE THE DH8C WAS ACROSS THE LNDG THRESHOLD FOR RWY 35. THIS ALERT CAUSED ME TO SEND THE DH8C AROUND AT VERY SHORT NOTICE; POSSIBLY CREATING A SITUATIONAL DISTR FROM OTHER PRESSING DUTIES AT THE TIME. IN RETROSPECT; THE GAR WAS NOT NEEDED; BUT CREATED BY AN ALERT TOLERANCE SETTING WITHIN THE AMASS SYS.

Data retrieved from NASA's ASRS site as of January 2009 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.