Background
On an instrument flight rules training flight, C-FFMW, a Piper Twin Comanche operated by Skys Un-Limited Air Service, departed Pitt Meadows, British Columbia. At 1039 Pacific daylight saving time, it was cleared for an ILS/DME 27 approach via the IMPOR STAR. N6857P, a Piper PA-24 Comanche from Aurora, Oregon, was inbound under instrument flight rules from the south, cleared to fly heading 360° at 3000 feet. C-GMET, a Fairchild Merlin 3 operated by Navair Charter, was on left downwind for runway 27. Weather was 3800 feet overcast with 20 nautical miles visibility.
Sequence of Events
At 1043:54 PDT, the trainee terminal controller instructed C-FFMW to reduce airspeed to 110 knots and later to descend to 3000 feet. Radar data showed C-FFMW deviating west of the Vancouver VOR 157° radial toward IMPOR by up to 2 nm; the trainee did not correct this. The on-the-job instructor (OJI) had cautioned the trainee about a possible tighter track but did not intervene. Subsequently, C-FFMW turned early to intercept the localizer, reducing spacing with N6857P to 1.87 nm laterally and 300 feet vertically (minimum separation is 3 nm or 1000 feet). The OJI took over control without coordinating with the trainee, vectoring C-FFMW south and N6857P north and parallel to the localizer.
Meanwhile, N6857P visually acquired the airport and turned onto right base, converging with C-GMET on left base. The Victoria tower controller instructed C-GMET to turn toward the runway button; N6857P executed a 360° orbit. Spacing was re-established, and all three aircraft landed safely.
Findings
The trainee did not correct C-FFMW's flight path deviation, and the OJI did not intervene. The OJI lacked access to landline communications from his position and did not inform the tower of his plan for N6857P. The trainee cleared both C-FFMW and N6857P to 3000 feet on converging tracks and changed the approach sequence without telling the OJI. Coordination failures occurred: the terminal data controller attempted to relay information via landline to the ground controller, but the message was misunderstood and not passed to the tower controller. The arrival controller did not switch N6857P to tower frequency until well inside the tower's airspace.
Post-Event Actions
The Victoria tower supervisor was unable to provide proper oversight as he was replacing the radar controller. Following the incident, the Vancouver ACC's Manager of Operations took action (details not specified in source).