Narrative:

2 aircraft on IFR clrncs under radar contact came within 1.7 NM while both were at 4000 ft. The civil aircraft, X, a PA28 checked in with crp approach at XA08Z. The ZHU ntap confirmed the altitude of X to be 4000 ft from well before point of closest proximity. Crp did not assign a different altitude or any control instructions -- he just issued the crp altimeter which the pilot read back. At XX09Z, military Y, a T34 on an assigned IFR missed approach was radar idented, instructed to climb to 4000 ft and to proceed direct to a fix the pilot had requested to proceed to. While conducting a position relief briefing the controller being relieved apparently saw the situation and issued evasive turns to both aircraft. TA's or safety alerts weren't issued until the T34 reported 9 O'clock traffic in sight. The ARTS conflict alert sounded in the same general time frame and printed a teletype message. This conflict alert and the center ntap agree the PA28 was at 4000 ft and the T34 was at 4200 ft. The conflict alert printout showed closest proximity was 1.684042 mi. The relieving crp controller reported the incident as an operational error to the TRACON supervisor. The supervisor said he later checked and found no conflict alert printout so he asked the relieved ATC specialist what had happened. The air traffic controllers said it was no error since he was using diverging courses and visual separation. A later confrontation between the 2 ATC specialists forced a next day review of voice tapes which revealed visual separation had not been used. The conflict alert printout was found the next day in clear sight. The conflict alert and ntap were discarded as inconclusive because the controller said he had diverging courses. The responsible controller had been recertified only 1 day before after a 4 month suspension for illegal drugs detected in a spot urinalysis. The employee was recertified for all 7 radar position after a single 1 hour evaluation on a single radar position with minimal traffic. He was very busy in the 15 mins before the error then traffic died down to 5 aircraft of which only 2 required attention. He allowed his attention to take a break after the traffic died down. He was simply not paying attention until it was too late.

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Original NASA ASRS Text

Title: MIL Y SAME ALT ASSIGNED HAD LTSS FROM ACFT X. SYS ERROR.

Narrative: 2 ACFT ON IFR CLRNCS UNDER RADAR CONTACT CAME WITHIN 1.7 NM WHILE BOTH WERE AT 4000 FT. THE CIVIL ACFT, X, A PA28 CHKED IN WITH CRP APCH AT XA08Z. THE ZHU NTAP CONFIRMED THE ALT OF X TO BE 4000 FT FROM WELL BEFORE POINT OF CLOSEST PROX. CRP DID NOT ASSIGN A DIFFERENT ALT OR ANY CTL INSTRUCTIONS -- HE JUST ISSUED THE CRP ALTIMETER WHICH THE PLT READ BACK. AT XX09Z, MIL Y, A T34 ON AN ASSIGNED IFR MISSED APCH WAS RADAR IDENTED, INSTRUCTED TO CLB TO 4000 FT AND TO PROCEED DIRECT TO A FIX THE PLT HAD REQUESTED TO PROCEED TO. WHILE CONDUCTING A POS RELIEF BRIEFING THE CTLR BEING RELIEVED APPARENTLY SAW THE SIT AND ISSUED EVASIVE TURNS TO BOTH ACFT. TA'S OR SAFETY ALERTS WEREN'T ISSUED UNTIL THE T34 RPTED 9 O'CLOCK TFC IN SIGHT. THE ARTS CONFLICT ALERT SOUNDED IN THE SAME GENERAL TIME FRAME AND PRINTED A TELETYPE MESSAGE. THIS CONFLICT ALERT AND THE CTR NTAP AGREE THE PA28 WAS AT 4000 FT AND THE T34 WAS AT 4200 FT. THE CONFLICT ALERT PRINTOUT SHOWED CLOSEST PROX WAS 1.684042 MI. THE RELIEVING CRP CTLR RPTED THE INCIDENT AS AN OPERROR TO THE TRACON SUPVR. THE SUPVR SAID HE LATER CHKED AND FOUND NO CONFLICT ALERT PRINTOUT SO HE ASKED THE RELIEVED ATC SPECIALIST WHAT HAD HAPPENED. THE AIR TFC CTLRS SAID IT WAS NO ERROR SINCE HE WAS USING DIVERGING COURSES AND VISUAL SEPARATION. A LATER CONFRONTATION BTWN THE 2 ATC SPECIALISTS FORCED A NEXT DAY REVIEW OF VOICE TAPES WHICH REVEALED VISUAL SEPARATION HAD NOT BEEN USED. THE CONFLICT ALERT PRINTOUT WAS FOUND THE NEXT DAY IN CLR SIGHT. THE CONFLICT ALERT AND NTAP WERE DISCARDED AS INCONCLUSIVE BECAUSE THE CTLR SAID HE HAD DIVERGING COURSES. THE RESPONSIBLE CTLR HAD BEEN RECERTIFIED ONLY 1 DAY BEFORE AFTER A 4 MONTH SUSPENSION FOR ILLEGAL DRUGS DETECTED IN A SPOT URINALYSIS. THE EMPLOYEE WAS RECERTIFIED FOR ALL 7 RADAR POS AFTER A SINGLE 1 HR EVALUATION ON A SINGLE RADAR POS WITH MINIMAL TFC. HE WAS VERY BUSY IN THE 15 MINS BEFORE THE ERROR THEN TFC DIED DOWN TO 5 ACFT OF WHICH ONLY 2 REQUIRED ATTN. HE ALLOWED HIS ATTN TO TAKE A BREAK AFTER THE TFC DIED DOWN. HE WAS SIMPLY NOT PAYING ATTN UNTIL IT WAS TOO LATE.

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