Beacon target of aircraft disappeared from radar scope for several minutes. Program should be change...

Attributes
ACN	109247
Time
Date	198904
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : sbn
State Reference	IN
Altitude	msl bound lower : 500 msl bound upper : 10000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sbn
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
ASRS Report	109247
Person 2
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument
Events
Anomaly	other anomaly other
Independent Detector	other controllera
Resolutory Action	none taken : detected after the fact
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other
Situations
ATC Facility	procedure or policy : unspecified

Narrative:

An aircraft I was working went 'no beacon,' dropped off the radar scope, and flew for several mins west/O my even knowing he was out there. We have ARTS ii at our facility. When the radar loses the transponder signal from an aircraft, 'nb' appears in its data block. This stays on the radar screen for just under a minute and then drops off. This leaves the controller with no reference at all on the screen that a plane should be there. During busy periods, the controller relies heavily on the screen data, and much less on the strips he is working. Although I was lucky today and no incident happened, I could have easily sent another aircraft through the missing aircraft's altitude. This problem can be easily solved by altering the ARTS ii program. The change would make the data block 'flash' at the controller and not drop during periods of no beacon. This would call attention to the no beacon, rather than drop it out.

Original NASA ASRS Text

Title: BEACON TARGET OF ACFT DISAPPEARED FROM RADAR SCOPE FOR SEVERAL MINUTES. PROGRAM SHOULD BE CHANGED TO PREVENT TARGET LOSS.

Narrative: AN ACFT I WAS WORKING WENT 'NO BEACON,' DROPPED OFF THE RADAR SCOPE, AND FLEW FOR SEVERAL MINS W/O MY EVEN KNOWING HE WAS OUT THERE. WE HAVE ARTS II AT OUR FAC. WHEN THE RADAR LOSES THE XPONDER SIGNAL FROM AN ACFT, 'NB' APPEARS IN ITS DATA BLOCK. THIS STAYS ON THE RADAR SCREEN FOR JUST UNDER A MINUTE AND THEN DROPS OFF. THIS LEAVES THE CTLR WITH NO REF AT ALL ON THE SCREEN THAT A PLANE SHOULD BE THERE. DURING BUSY PERIODS, THE CTLR RELIES HEAVILY ON THE SCREEN DATA, AND MUCH LESS ON THE STRIPS HE IS WORKING. ALTHOUGH I WAS LUCKY TODAY AND NO INCIDENT HAPPENED, I COULD HAVE EASILY SENT ANOTHER ACFT THROUGH THE MISSING ACFT'S ALT. THIS PROB CAN BE EASILY SOLVED BY ALTERING THE ARTS II PROGRAM. THE CHANGE WOULD MAKE THE DATA BLOCK 'FLASH' AT THE CTLR AND NOT DROP DURING PERIODS OF NO BEACON. THIS WOULD CALL ATTN TO THE NO BEACON, RATHER THAN DROP IT OUT.

Data retrieved from NASA's ASRS site as of August 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.

Beacon target of aircraft disappeared from radar scope for several minutes. Program should be changed to prevent target loss.