The crew of a 737 that crashed on approach to the airport in Resolute, Nunavut, tried to abort the landing attempt two seconds before impact, according to a progress report by the Transportation Safety Board of Canada.

Twelve people, including all four crew members, were killed Aug. 20 when the chartered First Air plane from Yellowknife crashed into a hill near the Resolute airport. Three passengers survived with serious injuries.

Transportation Safety Board of Canada investigators examine wreckage at the crash site of First Air flight 6560 in Resolute, Nunavut, in August. (Transportation Safety Board of Canada)

The report states the weather conditions required that the crew make an instrument-guided approach to the runway, and that the crew initiated a go-around — aborting the landing attempt — two seconds before impact.

The Transportation Safety Board of Canada is classifying the crash as a "controlled flight into terrain." The TSB defines a controlled flight into terrain as occurring when an aircraft under the control of the flight crew is flown unintentionally into terrain, obstacles or water.

"The engines were functioning normally at the time of the accident," said Brian MacDonald, the investigator in charge.

"Our field investigation in Resolute determined there was nothing structurally wrong with the aircraft. We have still yet to do further investigations with the flight and navigational instruments. That analysis is still ongoing."

The weather in the hours prior to the accident was variable with fluctuations in visibility and the height of the cloud ceiling. Forty minutes before the accident the visibility was 16 kilometres with a ceiling of about 213 metres. A weather observation taken just after the accident reported visibility of eight kilometres and a ceiling of 91 metres.

The report also states another aircraft successfully completed an instrument-guided landing at the airport 20 minutes after the crash.

The Resolute airport has no air traffic controllers, but a temporary “military control zone” had been established at the airport to handle the increased traffic due to a Canadian Forces exercise taking place that month.

The TSB says it is focusing its investigation on the aircraft’s navigation system, all aspects of training and procedures, and the establishment of the military control zone and operation and co-ordination of the airspace between military and civilian agencies.