Narrative:

On the evening shift of 12/thu/88 I was working sector 36 dvc high. Widebody transport X was handed off to me on my boundary by sector 4. Widebody transport X was cleared and proceeding direct obm. His course was eastbound approximately heading of 050 degrees. The mlt Y flight was northbound at FL350. Widebody transport X was eastbound at FL330. I never talked to the pilot of either aircraft. The sector 5 controller descended the mlt Y flight to FL310 for traffic and then while descending turned the mlt Y flight to the west (270 degree heading). The mlt Y flight ultimately became a head on confliction with the widebody transport X flight at a point where 4 sectors meet. The C/a went off alerting sector 5 controller of an imminent situation. Evasive action by pilots was not taken. Contributing factor was that there was a time delay for sector 5 in figuring out who was talking to widebody transport X. Sector 4 controller apparently saw the situation develop and did nothing sector 4 could have and should have turned widebody transport X away from mlt Y flight. This situation occurred because pointouts were not made to sector 5 in a timely manner on widebody transport X. Recently sector boundaries were moved creating this 4 corner situation. The previous boundary on sector 5 was about 20 mi east. Therefore, if boundary were moved sector 4 would have had control on both aircraft involved sooner. Perhaps change obh routing so aircraft don't run sector boundaries. Supplemental information from acn 100385: on 12/thu/88 at approximately XA08Z sector 5 observed a northbound flight of 3 (mlt Y) at FL350 in handoff to their sector. At the time sector 5 had 3 air carrier's wbound at FL350, 2 of which would conflict with the military formation flight. Sector 5 d-side coordinated with sector 25 (the sector with control of the military flight) and told them to descend mlt Y flight to FL310 for traffic. Sector 25 stated 'show it.' approximately 50 seconds later mlt Y flight was still showing level at FL350 so sector 5 d-side called again and told sector 25 to start mlt Y down to FL310 'now' and ship him to us. Prior to establishing communications with mlt Y, C/a started to flash. Sector 5 radar controller established communications with mlt Y and turned mlt Y left to a 270 degree heading for traffic and told the flight to report leaving FL330. The mlt Y flight had checked on leaving FL350 for FL310, and the other 2 aircraft which were in confliction had been turned to 250 degree headings. Sector 5 d-side immediately coordinated with sector 25 the left turn on mlt Y and then initiated a pointout to sector 36, the sector adjoining sector 25's west boundary, informing them of mlt Y turn to a 270 degree heading. Then direct meeker VOR descending to FL310 for traffic, sector 36 approved the pointout with no restrictions. Mlt Y was observed leaving FL330 for FL310 and cleared direct meeker within 3 seconds a limited data block was observed northeast bound at FL330. Sector 5 radar gave mlt Y an immediate right turn to a 360 degree heading and brought up a data block on widebody transport X at FL330. Sector 5 d-side called sector 36 and told them to turn widebody transport X south immediately for traffic. Sector 36 said sector 25 had the aircraft, sector 25 was called and said sector 36 had the aircraft. It was finally established that sector 4 had widebody transport X and had turned the aircraft south, but the turn did not begin till after separation standards were lost. Supplemental information from acn 100763: I noticed from the limited data block sector 5 had traffic FL350 wbound on J60 (17 NM north of 25/5 boundary) I started an early handoff on mlt Y to sector 5. Sector 5 called me and requested I start mlt Y down to FL310 for traffic. Which I did. Sector 5 took the handoff and I shipped the flight to sector 5. Sector 5 did not get immediate communications with mlt Y and called me back and said again to descend mlt Y immediately. I advised them it had been done and he should be on their frequency. They checked and the mlt Y flight was sitting on their frequency. The radar controller turned mlt Y left to a 270 degree heading west/O getting control for turns then back coordinated the turn. Widebody transport X had been handed off from sector 4 to sector 36, who then handed widebody transport X to sector 25 west/O talking to the aircraft. Sector 5 called sector 36 with a pointout on mlt Y turning left to 270 degree heading. Sector 36 said, 'pointout' approved. Thinking sector 4 had pointed out widebody transport X to sector 5 (sector 5 never got a pointout on widebody transport X) sector 4 also saw the confliction, was stilling talking to widebody transport X, but thought someone else would provide separation and never turned widebody transport X until after sep loss was inevitable. I was in the process of briefing my relief and widebody transport X had just come out from under the edge of the scope when the C/a went off. 33 seconds later sep was lost. Just prior to the C/a sector 5 saw the limited data block on widebody transport X and turned the mlt Y north to a 360 degree heading. The operational error occurred 3.7 mi southwest of the 4 corner boundary.

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Original NASA ASRS Text

Title: POOR COORDINATION AND ATC TECHNIQUE CREATE A HEADON LESS THAN STANDARD SEPARATION INCIDENT BETWEEN AN ACR-WDB AND A MLT FLT DESCENDING THROUGH ACR ALT.

Narrative: ON THE EVENING SHIFT OF 12/THU/88 I WAS WORKING SECTOR 36 DVC HIGH. WDB X WAS HANDED OFF TO ME ON MY BOUNDARY BY SECTOR 4. WDB X WAS CLRED AND PROCEEDING DIRECT OBM. HIS COURSE WAS EBND APPROX HDG OF 050 DEGS. THE MLT Y FLT WAS NBOUND AT FL350. WDB X WAS EBND AT FL330. I NEVER TALKED TO THE PLT OF EITHER ACFT. THE SECTOR 5 CTLR DSNDED THE MLT Y FLT TO FL310 FOR TFC AND THEN WHILE DSNDING TURNED THE MLT Y FLT TO THE W (270 DEG HDG). THE MLT Y FLT ULTIMATELY BECAME A HEAD ON CONFLICTION WITH THE WDB X FLT AT A POINT WHERE 4 SECTORS MEET. THE C/A WENT OFF ALERTING SECTOR 5 CTLR OF AN IMMINENT SITUATION. EVASIVE ACTION BY PLTS WAS NOT TAKEN. CONTRIBUTING FACTOR WAS THAT THERE WAS A TIME DELAY FOR SECTOR 5 IN FIGURING OUT WHO WAS TALKING TO WDB X. SECTOR 4 CTLR APPARENTLY SAW THE SITUATION DEVELOP AND DID NOTHING SECTOR 4 COULD HAVE AND SHOULD HAVE TURNED WDB X AWAY FROM MLT Y FLT. THIS SITUATION OCCURRED BECAUSE POINTOUTS WERE NOT MADE TO SECTOR 5 IN A TIMELY MANNER ON WDB X. RECENTLY SECTOR BOUNDARIES WERE MOVED CREATING THIS 4 CORNER SITUATION. THE PREVIOUS BOUNDARY ON SECTOR 5 WAS ABOUT 20 MI E. THEREFORE, IF BOUNDARY WERE MOVED SECTOR 4 WOULD HAVE HAD CONTROL ON BOTH ACFT INVOLVED SOONER. PERHAPS CHANGE OBH ROUTING SO ACFT DON'T RUN SECTOR BOUNDARIES. SUPPLEMENTAL INFO FROM ACN 100385: ON 12/THU/88 AT APPROX XA08Z SECTOR 5 OBSERVED A NBOUND FLT OF 3 (MLT Y) AT FL350 IN HDOF TO THEIR SECTOR. AT THE TIME SECTOR 5 HAD 3 ACR'S WBOUND AT FL350, 2 OF WHICH WOULD CONFLICT WITH THE MIL FORMATION FLT. SECTOR 5 D-SIDE COORDINATED WITH SECTOR 25 (THE SECTOR WITH CTL OF THE MIL FLT) AND TOLD THEM TO DSND MLT Y FLT TO FL310 FOR TFC. SECTOR 25 STATED 'SHOW IT.' APPROX 50 SECS LATER MLT Y FLT WAS STILL SHOWING LEVEL AT FL350 SO SECTOR 5 D-SIDE CALLED AGAIN AND TOLD SECTOR 25 TO START MLT Y DOWN TO FL310 'NOW' AND SHIP HIM TO US. PRIOR TO ESTABLISHING COMS WITH MLT Y, C/A STARTED TO FLASH. SECTOR 5 RADAR CTLR ESTABLISHED COMS WITH MLT Y AND TURNED MLT Y LEFT TO A 270 DEG HDG FOR TFC AND TOLD THE FLT TO RPT LEAVING FL330. THE MLT Y FLT HAD CHKED ON LEAVING FL350 FOR FL310, AND THE OTHER 2 ACFT WHICH WERE IN CONFLICTION HAD BEEN TURNED TO 250 DEG HDGS. SECTOR 5 D-SIDE IMMEDIATELY COORDINATED WITH SECTOR 25 THE LEFT TURN ON MLT Y AND THEN INITIATED A POINTOUT TO SECTOR 36, THE SECTOR ADJOINING SECTOR 25'S W BOUNDARY, INFORMING THEM OF MLT Y TURN TO A 270 DEG HDG. THEN DIRECT MEEKER VOR DSNDING TO FL310 FOR TFC, SECTOR 36 APPROVED THE POINTOUT WITH NO RESTRICTIONS. MLT Y WAS OBSERVED LEAVING FL330 FOR FL310 AND CLRED DIRECT MEEKER WITHIN 3 SECS A LIMITED DATA BLOCK WAS OBSERVED NE BOUND AT FL330. SECTOR 5 RADAR GAVE MLT Y AN IMMEDIATE RIGHT TURN TO A 360 DEG HDG AND BROUGHT UP A DATA BLOCK ON WDB X AT FL330. SECTOR 5 D-SIDE CALLED SECTOR 36 AND TOLD THEM TO TURN WDB X S IMMEDIATELY FOR TFC. SECTOR 36 SAID SECTOR 25 HAD THE ACFT, SECTOR 25 WAS CALLED AND SAID SECTOR 36 HAD THE ACFT. IT WAS FINALLY ESTABLISHED THAT SECTOR 4 HAD WDB X AND HAD TURNED THE ACFT S, BUT THE TURN DID NOT BEGIN TILL AFTER SEPARATION STANDARDS WERE LOST. SUPPLEMENTAL INFO FROM ACN 100763: I NOTICED FROM THE LIMITED DATA BLOCK SECTOR 5 HAD TFC FL350 WBOUND ON J60 (17 NM N OF 25/5 BOUNDARY) I STARTED AN EARLY HDOF ON MLT Y TO SECTOR 5. SECTOR 5 CALLED ME AND REQUESTED I START MLT Y DOWN TO FL310 FOR TFC. WHICH I DID. SECTOR 5 TOOK THE HDOF AND I SHIPPED THE FLT TO SECTOR 5. SECTOR 5 DID NOT GET IMMEDIATE COMS WITH MLT Y AND CALLED ME BACK AND SAID AGAIN TO DSND MLT Y IMMEDIATELY. I ADVISED THEM IT HAD BEEN DONE AND HE SHOULD BE ON THEIR FREQ. THEY CHKED AND THE MLT Y FLT WAS SITTING ON THEIR FREQ. THE RADAR CTLR TURNED MLT Y LEFT TO A 270 DEG HDG W/O GETTING CTL FOR TURNS THEN BACK COORDINATED THE TURN. WDB X HAD BEEN HANDED OFF FROM SECTOR 4 TO SECTOR 36, WHO THEN HANDED WDB X TO SECTOR 25 W/O TALKING TO THE ACFT. SECTOR 5 CALLED SECTOR 36 WITH A POINTOUT ON MLT Y TURNING LEFT TO 270 DEG HDG. SECTOR 36 SAID, 'POINTOUT' APPROVED. THINKING SECTOR 4 HAD POINTED OUT WDB X TO SECTOR 5 (SECTOR 5 NEVER GOT A POINTOUT ON WDB X) SECTOR 4 ALSO SAW THE CONFLICTION, WAS STILLING TALKING TO WDB X, BUT THOUGHT SOMEONE ELSE WOULD PROVIDE SEPARATION AND NEVER TURNED WDB X UNTIL AFTER SEP LOSS WAS INEVITABLE. I WAS IN THE PROCESS OF BRIEFING MY RELIEF AND WDB X HAD JUST COME OUT FROM UNDER THE EDGE OF THE SCOPE WHEN THE C/A WENT OFF. 33 SECS LATER SEP WAS LOST. JUST PRIOR TO THE C/A SECTOR 5 SAW THE LIMITED DATA BLOCK ON WDB X AND TURNED THE MLT Y N TO A 360 DEG HDG. THE OPERROR OCCURRED 3.7 MI SW OF THE 4 CORNER BOUNDARY.

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.