Incident at ST. ANTHONY AIRPORT (TCAS alert, Conflict - loss of separation)

1997-03-18: AFR047(air France) was enroute from Mirabel to Paris and UAL946(United Airlines) was enroute from Washington to Amsterdam, both eastbound at FL370 Their tracks crossed about 150 NM southwest of St. Anthony. Both aircraft were in a radar enviroment and were being worked by a controller trainee with a controller monitor in position. When the separation was reduced to about 20 nm the trainee provided a vector that was intended to turn AFR047 in behind UAL946. AFR047 questioned the controllee as the vector would turn him towards UAL946 that he had visually. The vector was confirmed and AFR047 proceeded to make the turn. At the same time UAL946 received a TCAS resolution advisory and took evasive action by climbing to FL37.7. When the controller saw that the turn was not providing the required separation, he descended AFR047. The separation was 3.5 miles when it should have been 5.