PRIMARY RADAR FAILS WHILE ATTEMPTING TO VECTOR AN EMER ACFT BACK TO THE ARPT.

Narrative

ON 12/92; WHILE WORKING SMA X; A HELI DEPARTING OFF OF ERIE ADVISED ME THAT HE HAD STRANGE NOISE AND WISHED TO RETURN TO THE ARPT. THE WX AT THE TIME WAS SOLID IFR WITH A LOW CEILING AND VISIBILITY. I ADVISED SMA X THAT I COULD VECTOR HIM BACK FOR AN ILS 24 AND THAT WE WERE GOING TO CALL THE CFR EQUIP (AS A PRECAUTION) AT THAT TIME HE ADVISED THE NOISE WAS NOW WORSE AND I ADVISED SMA X HE WAS NOW BEING VECTORED FOR AN ASR RWY 24 APCH. AS I STARTED THE NORMAL PROC FOR AN ASR RWY 24 THE ARTS (ALPHA NUMERIC DISPLAY) FROZE UP ON THE RADAR SCOPE. AT THE SAME MOMENT I LOST ALL PRIMARY TARGETS. I ADVISED SMA X THAT RADAR CONTACT WAS LOST AND SUGGESTED HE CONTINUE NBOUND WHICH WOULD PUT THE ACFT OUT OVER LAKE ERIE AND AWAY FROM ANY CONGESTED AREAS. THE SUPVR ON DUTY DECLARED AN EMER. ANOTHER SUPVR IN THE TWR SAID HE HAD THE HELI IN RADAR ON THE TWR DISPLAY (THIS IS IMPOSSIBLE) AND THAT HE WOULD VECTOR SMA X TO THE ARPT. ALL THEY HAD IN THE TWR WAS BEACON RETURNS AND THAT IS WHAT THE SUPVR USED TO VECTOR SMA X. THE MAINT TECH DOES NOT HAVE ANY IDEA HOW THE ARTS FROZE OR PRIMARY TARGETS WERE LOST. SMA X LANDED WITHOUT ANY INCIDENT.