ATC EQUIP PROB RADAR SHUTDOWN FOR MAINT.

Narrative

ON A TOO FREQ BASIS; MAINT PERSONNEL ARE ALLOWED TO TAKE COMPONENTS OF ATC RADAR OTS DURING OPERATIONAL HRS OF A PART-TIME TWR. ON THE FIRST DATE MENTIONED THE RADAR WAS TAKEN DOWN FOR ALMOST 4 HRS FOR MODIFICATION. ALTHOUGH BACKUP CTR RADAR WAS AVAILABLE AND USED. IT DOES NOT FUNCTION NEARLY AS WELL AS FAR AS UPDATES AND COVERAGE. ALSO ALT INFO FROM THIS SYS CANNOT BE USED AND MUST BE VERBALLY VERIFIED INCREASING RISK TO SAFETY AND CTLR WORKLOAD. ON THE SECOND OCCASION; THE COMPUTER WAS TAKEN OTS FOR A MODIFICATION 2 DAYS IN A ROW. FOR A PERIOD OF 2 HRS AT A TIME. THIS OCCURRENCE ALSO OCCURS WKLY FOR MAINT CHKS FOR A PERIOD OF 10-30 MINS. WHEN THIS OCCURS; ALL THAT IS AVAILABLE IS A PRIMARY AND SECONDARY RADAR TARGET. THERE IS NO ALT; CALL SIGN; DISCRETE XPONDER CODES; ETC; TO AID THE CTLR. EVERY TARGET ON THE SCOPE APPEARS THE SAME; EVEN HIGH ALT TFC. SINCE THE BACKUP CTR RADAR HAS BECOME AVAILABLE; RADAR OUTAGES HAVE INCREASED. NOT FROM FAILURE; BUT FROM TECHNICIANS USING THIS AS A CONVENIENCE OUTLET TO AVOID OVERTIME; MID SHIFTS; ETC. OUR FACILITY IS CLOSED 8 HRS ON MID SHIFT. THIS IS AMPLE TIME IN MOST CASES TO DO WHAT THEY NEED TO DO.