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Non-standard phraseology contributed to risk of collision at Ottawa
15 July 2015
Ottawa Macdonald-Cartier International Airport layout (Google/TSB)

Ottawa Macdonald-Cartier International Airport layout (Google/TSB)

The Transportation Safety Board of Canada (TSB) released its investigation report into the June 2014 runway incursion and risk of collision at the Ottawa International Airport between a medevac helicopter and an A300 cargo plane. 

An Agusta AW139 helicopter, registration C-GYNM, operating as Life Flight 4 Medevac, was on an IFR flight plan from the Ottawa Macdonald-Cartier International Airport, Ontario, to Pembroke, Ontario. The flight received taxi instructions and was instructed to contact the tower when holding short of runway 25. A correct readback was obtained by the ground controller, and the Medevac crew contacted the tower when holding short of runway 25. The airport controller acknowledged, amended LF 4 Medevac’s IFR clearance by stating: “LF 4 Medevac Roger, while we wait amend your Ottawa 3 for a right turn heading 290˚ balance unchanged”.
The tower controller then observed the AW139 taxiing across the hold short line while an Airbus A300B4-622R operating as Federal Express Flight 152 Heavy, was landing on runway 25. The airport controller instructed LF 4 Medevac to stop. When LF 4 Medevac stopped taxiing, FDX 152 Heavy was decelerating through a ground speed of 110 knots, approximately 2600 feet from the intersection of runway 25 and Taxiway Echo.

Findings as to causes and contributing factors:
1. While holding short of Runway 25 on Taxiway Echo, Life Flight 4 Medevac was given an amendment to its instrument flight rules clearance. The airport controller’s first transmission to Life Flight 4 Medevac began with non-standard phraseology “while we wait”, which can be confused with “line up and wait”.
2. Based on experience when departing the Ottawa Macdonald-Cartier International Airport on an instrument flight rules flight, the Life Flight 4 Medevac pilot flying expected that a clearance to take off would follow the amendment to the instrument flight rules clearance.
3. The probable distraction caused by listening to and processing the amendment, while setting the new heading on the heading bug, likely resulted in the Life Flight 4 Medevac pilot flying not checking if the runway was clear before taxiing across the hold short line, leading to the runway incursion.
4. There was a risk of collision as Federal Express Flight 152 Heavy was landing on Runway 25 and Life Flight 4 Medevac was taxiing across the hold short line on Taxiway Echo proceeding to Runway 25.

Findings as to risk:
1. If air traffic control uses non-standard phraseology, there is a risk of inconsistencies and miscommunication between air traffic control and the pilot.
2. If flight crews do not follow company standard operating procedures before taxiing onto a runway, there is an increased risk of collision between aircraft.

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