Incident at CALGARY INTL AB (CYYC) (Conflict - near collision (VFR or IFR), Conflict - loss of separation, ATS operating irregularity)
2001-02-15: UPDATE ANS and Airspace reported that after further investigation, NAV CANADA has decided to convene a Fact Finding Board concerning this occurrence.
2001-02-01: UPDATE ANS and Airspace reported that NAV CANADA´s preliminary investigation determined that in the airspace where this occurrence happened (Class ¿D¿), conflict resolution is only provided if requested. In this case it wasn´t, traffic information had been passed correctly. The preliminary investigation also determined that the interunit agreement was adhered to. However, the interunit agreement has been revised so that in the future, the lowest altitude to be approved for the Calgary inbounds in the Class C airspace in this area will be not lower that 7,000 feet.
2001-01-12: Subsequent to controller intervention, CDN 3518, a B737, (IFR) and C-GYDE, a Cessna 172,(VFR)passed each other in Class D airspace with .5 NM and 500 feet vertical separation. CDN 3518 was inbound to Calgary (YYC) from the west, planning a landing on Runway 10. The Calgary Terminal Co-ordinator called Springbank Tower for approval for lower as per agreement. The Tower Controller approved 6,500 feet for CDN 3518. The Arrival Controller then cleared CDN 3518 to 6,500 feet. A short time later, C-GYDE departed Springbank on a local flight and was climbing northbound. At approximately 2227Z, the Arrival Controller observed CDN 3518 and C-GYDE outside the Springbank control zone (in Class D airspace) on converging tracks, both at 6,500 feet. The Controller instructed the crew of CDN 3518 to descend to 6,000 feet and passed traffic. CDN 3518 descended and reported the traffic in sight. A review of local procedures is under way. TSB is also looking into this occurrence.
|Occurred At||- 22:28|
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