Planes missed each other by 14 seconds: Transportation Safety Board
Probe blames lack of co-ordination
The ground controller ... applied the usual practice of clearing aircraft ... without co-ordinating with the tower controller.
The opening of a rarely used runway and a failure of co-ordination between ground crews and the flight tower resulted in two planes at Calgary International Airport missing each other by just 14 seconds, says Canada’s Transportation Safety Board.
An investigation report released by the agency Monday found that on Dec. 2, 2016, Air Canada flight 221 had been cleared for takeoff on infrequently used Runway 29 about the same time a Sunwest Aviation cargo aircraft was given clearance to taxi along a taxiway that intersected the north-south runway.
Investigators found strong westerly winds prompted airport officials to open the rarely used runway, intersected by a taxiway that ground crews commonly cleared for aircraft and vehicle movement, without prior co-ordination with the control tower.
“During the takeoff roll, the flight crew saw a Sunwest Aviation cargo aircraft crossing Runway 29 on Taxiway A,” the report read.
“Because the Sunwest aircraft was more than halfway across Runway 29 at that time, the Air Canada crew elected to continue with the takeoff, which was completed without further incident.”
A timeline of events prepared by the TSB found both aircraft had been separately cleared by ground crew sand the control tower, which ultimately resulted in what the TSB called a “runway incursion.” According to the timeline, the cargo plane crossed the centre line of Runway 29 just 14 seconds before the Air Canada flight crossed the taxiway airborne, at about 250 km/h.
“The investigation determined that the runway incursion occurred after the ground controller cleared the Sunwest aircraft to cross Runway 29, while the Air Canada flight was departing,” the report said.
“The ground controller, who was simultaneously overseeing the movement of two other aircraft, inadvertently applied the usual practice of clearing aircraft to cross Runway 29 without co-ordinating with the tower controller.”
According to the TSB, there have been four other runway incursions involving Runway 29 since the airport began running parallel runway operations in 2014.
Since the incident, Nav-Canada— the not-for-profit corporation that owns and operates Canada’s civil air navigation system — has implemented new procedures including better communication when the runway is open, a new “monitor” control position and modifications to the computer display system along with other measures.
A statement from airport officials said they continue to work closely with Nav Canada on safety measures.
“Safety is a critical component of everything we do at YYC. We continue to be actively engaged with Nav Canada to advance safety systems and procedures at YYC, and we support the additional processes that have been implemented at Calgary International Airport,” it said. “Nav Canada is a key partner in ensuring our airlines and passengers are safe and we will continue to work closely and collaborate with Nav Canada as YYC continues to grow.”