Narrative:

Air carrier X made a 90 degree left turn for course correction west/O warning, causing a confliction with air carrier Y at FL350 who was previously called as traffic for X. Air carrier Y was descended to FL330 and air carrier X was turned left and told to climb, but his ceiling was FL350. These actions were taken just prior to C/a, which went off with 5.3 mi. Callback conversation with reporter revealed the following: reporter is developmental, but was checked out on this sector. After incident was decertified and 2 weeks later recertified. Air carrier X was ahead of Y on J134 and 2000' below Y. When X continued on J134 controller thought X was cleared that arwy. When X then requested climb to FL350 controller approved because X and Y were diverging. Extreme turn by X to recapture J6 was big surprise to controller. Corrective action time was not enough to save standard sep. Discussed fact that aircraft often have trouble navigating the 3 arwys in that area (J149, J134 and J6) due to poor NAVAID quality. Controllers have submitted ucr's. Aircraft sometimes need vectors to navigation these arwys. Supplemental information from acn 96795: I told center that we had the traffic in sight. After that another controller came on and asked why we had turned to the south. We explained the problem with the scalloping hvq VOR and that we were just trying to get back on the centerline of J6. I am filing this report because I feel from the questioning by center that there is a possibility that vertical/horizontal sep was compromised. Not having the big (radar) picture my best guess is that we had an aircraft behind us at 5 mi and by turning from approximately 270 degrees to 190 degrees to recapture J6 the horizontal sep was reduced to below 5 mi and the other aircraft was descended to avoid conflict. My conclusions from this incident are as follows: use the aviation trust fund money to upgrade VOR's like hvq (and many others) so they are good and strong and do not scallop. When navigating on such aforementioned VOR's ask center for vector headings instead. That would put sep on their shoulders and avoid problems like the one described above. If you find it necessary to make large heading changes to get on course, call center first, even if you feel that you are within your allotted airspace.

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Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION BETWEEN 2 ACR. OPERATIONAL ERROR AND PLT DEVIATION.

Narrative: ACR X MADE A 90 DEG LEFT TURN FOR COURSE CORRECTION W/O WARNING, CAUSING A CONFLICTION WITH ACR Y AT FL350 WHO WAS PREVIOUSLY CALLED AS TFC FOR X. ACR Y WAS DSNDED TO FL330 AND ACR X WAS TURNED LEFT AND TOLD TO CLB, BUT HIS CEILING WAS FL350. THESE ACTIONS WERE TAKEN JUST PRIOR TO C/A, WHICH WENT OFF WITH 5.3 MI. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: RPTR IS DEVELOPMENTAL, BUT WAS CHKED OUT ON THIS SECTOR. AFTER INCIDENT WAS DECERTIFIED AND 2 WKS LATER RECERTIFIED. ACR X WAS AHEAD OF Y ON J134 AND 2000' BELOW Y. WHEN X CONTINUED ON J134 CTLR THOUGHT X WAS CLRED THAT ARWY. WHEN X THEN REQUESTED CLB TO FL350 CTLR APPROVED BECAUSE X AND Y WERE DIVERGING. EXTREME TURN BY X TO RECAPTURE J6 WAS BIG SURPRISE TO CTLR. CORRECTIVE ACTION TIME WAS NOT ENOUGH TO SAVE STANDARD SEP. DISCUSSED FACT THAT ACFT OFTEN HAVE TROUBLE NAVIGATING THE 3 ARWYS IN THAT AREA (J149, J134 AND J6) DUE TO POOR NAVAID QUALITY. CTLRS HAVE SUBMITTED UCR'S. ACFT SOMETIMES NEED VECTORS TO NAV THESE ARWYS. SUPPLEMENTAL INFO FROM ACN 96795: I TOLD CENTER THAT WE HAD THE TFC IN SIGHT. AFTER THAT ANOTHER CTLR CAME ON AND ASKED WHY WE HAD TURNED TO THE S. WE EXPLAINED THE PROB WITH THE SCALLOPING HVQ VOR AND THAT WE WERE JUST TRYING TO GET BACK ON THE CENTERLINE OF J6. I AM FILING THIS RPT BECAUSE I FEEL FROM THE QUESTIONING BY CENTER THAT THERE IS A POSSIBILITY THAT VERT/HORIZ SEP WAS COMPROMISED. NOT HAVING THE BIG (RADAR) PICTURE MY BEST GUESS IS THAT WE HAD AN ACFT BEHIND US AT 5 MI AND BY TURNING FROM APPROX 270 DEGS TO 190 DEGS TO RECAPTURE J6 THE HORIZ SEP WAS REDUCED TO BELOW 5 MI AND THE OTHER ACFT WAS DSNDED TO AVOID CONFLICT. MY CONCLUSIONS FROM THIS INCIDENT ARE AS FOLLOWS: USE THE AVIATION TRUST FUND MONEY TO UPGRADE VOR'S LIKE HVQ (AND MANY OTHERS) SO THEY ARE GOOD AND STRONG AND DO NOT SCALLOP. WHEN NAVIGATING ON SUCH AFOREMENTIONED VOR'S ASK CENTER FOR VECTOR HDGS INSTEAD. THAT WOULD PUT SEP ON THEIR SHOULDERS AND AVOID PROBS LIKE THE ONE DESCRIBED ABOVE. IF YOU FIND IT NECESSARY TO MAKE LARGE HDG CHANGES TO GET ON COURSE, CALL CENTER FIRST, EVEN IF YOU FEEL THAT YOU ARE WITHIN YOUR ALLOTTED AIRSPACE.

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.