Narrative:

This is not an anomaly or an isolated occurrence. The FAA acknowledges that fact. The FAA does not; however; view this as significant. I do. Our primary radar system; or host; does not display all transponder-equipped (discrete or non-discrete codes) aircraft in the area of jbr (jonesboro; ar); even though these aircraft are in areas of known radar coverage. I was working an IFR aircraft in the jbr area at 4000 ft (displayed on radar); and there were VFR aircraft in the area that I was not depicting on radar. 1 aircraft 3 mi southwest of jbr at 2500 ft; 1 aircraft 12 mi southwest of jbr at 4500 ft; and another aircraft 5 mi north of jbr at 3500 ft. None of these aircraft were depicted on host radar. However; our backup system; darc/ebus; was displaying these aircraft on radar; which is the only reason I knew they were there. This is a common occurrence; every day; all day. I've even had an aircraft as high as 11000 ft that was not depicted on my radar scope. This is a safety issue. I cannot; contrary to the statement by management; continue to rely on the integrity of the radar display.

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Original NASA ASRS Text

Title: ZME CTLR EXPRESSED CONCERN REGARDING THE HOST RADAR COVERAGE AS COMPARED TO THE BACK UP DARC-EBUS EQUIP.

Narrative: THIS IS NOT AN ANOMALY OR AN ISOLATED OCCURRENCE. THE FAA ACKNOWLEDGES THAT FACT. THE FAA DOES NOT; HOWEVER; VIEW THIS AS SIGNIFICANT. I DO. OUR PRIMARY RADAR SYS; OR HOST; DOES NOT DISPLAY ALL XPONDER-EQUIPPED (DISCRETE OR NON-DISCRETE CODES) ACFT IN THE AREA OF JBR (JONESBORO; AR); EVEN THOUGH THESE ACFT ARE IN AREAS OF KNOWN RADAR COVERAGE. I WAS WORKING AN IFR ACFT IN THE JBR AREA AT 4000 FT (DISPLAYED ON RADAR); AND THERE WERE VFR ACFT IN THE AREA THAT I WAS NOT DEPICTING ON RADAR. 1 ACFT 3 MI SW OF JBR AT 2500 FT; 1 ACFT 12 MI SW OF JBR AT 4500 FT; AND ANOTHER ACFT 5 MI N OF JBR AT 3500 FT. NONE OF THESE ACFT WERE DEPICTED ON HOST RADAR. HOWEVER; OUR BACKUP SYS; DARC/EBUS; WAS DISPLAYING THESE ACFT ON RADAR; WHICH IS THE ONLY REASON I KNEW THEY WERE THERE. THIS IS A COMMON OCCURRENCE; EVERY DAY; ALL DAY. I'VE EVEN HAD AN ACFT AS HIGH AS 11000 FT THAT WAS NOT DEPICTED ON MY RADAR SCOPE. THIS IS A SAFETY ISSUE. I CANNOT; CONTRARY TO THE STATEMENT BY MGMNT; CONTINUE TO RELY ON THE INTEGRITY OF THE RADAR DISPLAY.

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.