Bos local controller describes go around event prompted by an amass alert.

Attributes
ACN	680468
Time
Date	200512
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : bos.airport
State Reference	MA
Altitude	msl single value : 200
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : bos.tower
Operator	common carrier : air taxi
Make Model Name	Cessna 402/402C/B379 Businessliner/Utiliner
Operating Under FAR Part	Part 91
Flight Phase	descent : approach landing : go around
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tower : bos.tower
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	ground : taxi
Person 1
Affiliation	government : faa
Function	controller : local
Qualification	controller : radar
Experience	controller non radar : 5 controller radar : 18
ASRS Report	680468
Person 2
Affiliation	company : air taxi
Function	flight crew : captain oversight : pic
Events
Anomaly	conflict : ground less severe
Independent Detector	atc equipment other atc equipment : amass other controllera
Resolutory Action	controller : issued new clearance flight crew : executed go around
Supplementary
Problem Areas	FAA Navigational Facility
Primary Problem	Navigational Facility

Narrative:

Aircraft X (C402) was on short final to runway 33L and was cleared to land. Amass issued a go around alert; indicating runway 33L was occupied. Runway was clear of all aircraft. Previous aircraft had crossed and was well clear. Possible causes were amass was in wrong confign due to upcoming runway change; and blowing snow from crossing aircraft. Aircraft X was sent around for alert.

Original NASA ASRS Text

Title: BOS LCL CTLR DESCRIBES GAR EVENT PROMPTED BY AN AMASS ALERT.

Narrative: ACFT X (C402) WAS ON SHORT FINAL TO RWY 33L AND WAS CLRED TO LAND. AMASS ISSUED A GAR ALERT; INDICATING RWY 33L WAS OCCUPIED. RWY WAS CLR OF ALL ACFT. PREVIOUS ACFT HAD CROSSED AND WAS WELL CLR. POSSIBLE CAUSES WERE AMASS WAS IN WRONG CONFIGN DUE TO UPCOMING RWY CHANGE; AND BLOWING SNOW FROM XING ACFT. ACFT X WAS SENT AROUND FOR ALERT.

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.