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Air transportation safety investigation A16P0230

The TSB has completed this investigation. The report was published on 12 October 2017.

Table of contents

Temporary difficulty with aircraft control

Blackcomb Helicopters LP
Aérospatiale AS355N, C-FELE
Squamish, British Columbia

View final report

The occurrence

On 30 December 2016, an Airbus AS355N operated by Blackcomb Helicopters LP, was on a flight that had originated from Squamish Airport (CYSE) in British Columbia with one pilot and one passenger on board. After climbing above the freezing level, the pilot experienced difficulty in controlling the helicopter. The pilot was able to steer the aircraft back to CYSE, and control returned to normal when the helicopter was on final approach and below the freezing level. The pilot was able to land the helicopter without further issues. Preliminary examination did not reveal any damage or anomalies.


Investigation information

Map showing the location of the occurrence




Investigator-in-charge

Photo of Bill Yearwood

Bill Yearwood got his first flying lessons on fixed-wing aircraft at 13 and was flying helicopters by the time he was 20. He holds an Airline Transport license, and has accumulated more than 10,000 flight hours in a wide variety of operations across Canada and in South America. These include: heli-logging, medevac, Arctic and offshore exploration, flight training and certification flight testing.

After 18 years of commercial flying, Mr. Yearwood joined Transport Canada in the Pacific region, where he worked as an Air Carrier Inspector and then as the Regional Manager of System Safety. During his time at Transport Canada he was a check pilot, helped draft the Canadian Aviation Regulations and helped perform audits of operations around the world.

Mr. Yearwood joined the TSB in 1999 as the Regional Manager and has worked as the Investigator-in-Charge on several aviation occurrences. He has worked diligently to improve safety in aviation, and is well known in the West Coast aviation community.


  Download high-resolution photos from the TSB Flickr page.

Class of investigation

This is a class 4 investigation. These investigations are limited in scope, and while the final reports may contain limited analysis, they do not contain findings or recommendations. Class 4 investigations are generally completed within 220 days. For more information, see the Policy on Occurrence Classification.

TSB investigation process

There are 3 phases to a TSB investigation

  1. Field phase: a team of investigators examines the occurrence site and wreckage, interviews witnesses and collects pertinent information.
  2. Examination and analysis phase: the TSB reviews pertinent records, tests components of the wreckage in the lab, determines the sequence of events and identifies safety deficiencies. When safety deficiencies are suspected or confirmed, the TSB advises the appropriate authority without waiting until publication of the final report.
  3. Report phase: a confidential draft report is approved by the Board and sent to persons and corporations who are directly concerned by the report. They then have the opportunity to dispute or correct information they believe to be incorrect. The Board considers all representations before approving the final report, which is subsequently released to the public.

For more information, see our Investigation process page.

The TSB is an independent agency that investigates air, marine, pipeline, and rail transportation occurrences. Its sole aim is the advancement of transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.