Air transportation safety investigation A19A0055

Updated in September 2019 : This investigation is in the examination and analysis phase.

Table of contents

Inadvertent descent during landing

Canadian Helicopters Offshore
Sikorsky S-92
Southwest of Sable Island, Nova Scotia

The occurrence

On , a Sikorsky S-92 helicopter operated by Canadian Helicopters Offshore was conducting a flight between Stanfield/Halifax International airport (CYHZ) and the Thebaud gas field platform southwest of Sable Island, NS, with 2 crew and 11 passengers on board when it experienced a drop in altitude while approaching the platform. The helicopter pilots elected to return to CYHZ, where a landing was conducted without further incident. No injuries were reported. The TSB is investigating.


Investigation information

Map showing the location of the occurrence


Investigator-in-charge

Photo of Daryl Collins

Daryl Collins joined the TSB in 2009 after a 20 year career with the Canadian Armed Forces, having flown as a search and rescue helicopter pilot on the CH146 Griffon, the CH113 Labrador, and the CH149 Cormorant helicopter. In his last position with the Canadian Forces, Mr. Collins was the Commanding Officer of 103 Search and Rescue Squadron based out of Gander, Newfoundland and Labrador.

During his time with the Canadian Forces, Mr. Collins was responsible for the development and implementation of Canadian Forces-wide human performance training for all aircrew, maintenance, and air traffic control personnel and was heavily involved in flight safety. In addition, he obtained a Masters of Aeronautical Science with a dual specialization in Human Factors and System Safety.

Since joining the TSB, Mr. Collins has been actively involved in numerous accident investigations.

Mr. Collins holds an Airline Transport Licence – Helicopter with over 3200 hours of flying experience.


  Download high-resolution photos from the TSB Flickr page.

Class of investigation

This is a class 3 investigation. These investigations analyze a small number of safety issues, and may result in recommendations. Class 3 investigations are generally completed within 450 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.

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