Incident at WINNIPEG / JAMES ARMSTRONG RICHARDSON INTL MB (CYWG) (ATS operating irregularity)

1996-06-01: An operating irregularity - the following incident occurred in the north high sector near the boundary with Winnipeg east sector. Northwest Territorial Airways (NWT962), a B737 was proceeding Rankin Inlet to Churchill to - Winnipeg at FL310. Northwest Orient Airlines (NWA69), B74F, was proceeding KDTW to RJBB, via RL NCA20 5412N100W, also at FL310. Both aircraft estimates had been input to NADS which indicated 6 minutes separation when the tracks crossed. Subsequent time revisions were not updated due to increased workload in the sector. The north high controller requested assistance and another controller took over the radar position. As NWT962 approached the sector boundary, the north high radar controller observed a northwest bound target approaching his area. He activated the ""ALL"" button to display the data tag on the target which turned out to be NWA69. The controller initially tried to clear NWA69 to FL290, then realizing this flight was not on his frequency, issued the same instruction to NWT962. NWT962 commenced descent when the two aircraft were 10 miles apart and levelled off at FL290 when they were 3 miles apart. Neither pilot reported a TCAS activation.