Backgrounder

Findings from TSB investigation M21A0065: Capsizing and loss of life of the fishing vessel Tyhawk

Investigations conducted by the Transportation Safety Board of Canada (TSB) are complex since an accident rarely results from a single cause. In the case of the April 2021 capsizing of the fishing vessel Tyhawk (M21A0065) which resulted in the death of two crew members, several factors led to the sinking. The seven findings below detail the causes and contributing factors that led to this occurrence. Additionally during the course of the investigation, the TSB also made three findings as to risk and one other finding.

Findings as to causes and contributing factors

These are conditions, acts or safety deficiencies that were found to have caused or contributed to this occurrence.

  1. The removable deck, unsecured gear, and accumulation of rain and freezing rain above the waterline caused the vessel’s centre of gravity to be raised and the freeboard to be lowered.
  2. The open construction of the vessel meant that the vessel did not shed water from the decks, causing water accumulation on deck and in the bilge.
  3. The cumulative effects of stability factors and the resulting free surface effects compromised the vessel’s stability to the point that it capsized.
  4. Because the lifejackets, immersion suits, and personal flotation devices were not accessible and the unsecured life raft had shifted out of reach, when the vessel capsized, the crew were exposed to the cold water without flotation or protection from the elements, which contributed to the loss of life of 1 crew member and to another crew member being declared missing.
  5. To obtain needed sleep, all but 1 crew member were napping in the accommodation space. The crew member who was at the wheel was not familiar with the operation of the vessel and its equipment, which, in the absence of a bilge alarm sounding, delayed the detection of the accumulating water in the engine compartment bilge and on the main deck.
  6. Sleep inertia likely affected the master’s recognition of the deteriorating situation and the effectiveness of the abandonment of the vessel.
  7. The master’s perception of risk in the planned fishing operation was influenced by several pressures, including economic and community incentives, approvals and certificates, and previous successful experiences. As a result, the master departed for the fishing grounds likely believing the vessel was stable and well adapted for the snow crab fishery.

Findings as to risk

These are conditions, unsafe acts or safety deficiencies that were found not to be a factor in this occurrence but could have adverse consequences in future occurrences.

  1. Without an objective definition of a major modification, the impact on vessel stability of a major modification may not be identified by authorized representatives, masters, and Transport Canada. As a result, there is a risk that vessels will operate without adequate stability for their intended operations.
  2. Safety standards are based on vessel gross tonnage. Without an accurate and timely measurement of gross tonnage, the standards that apply to a vessel may change, making it difficult for authorized representatives to comply with safety standards and for regulators to consistently enforce them.
  3. When fisheries resource management measures and decisions do not consider the interactions among economic, conservation, and safety factors, including their cumulative effects, then decisions may be made for new and complex situations without adequate identification of safety hazards, increasing safety risks for fish harvesters.

Other findings

These items could enhance safety, resolve an issue of controversy, or provide a data point for future safety studies.

  1. In this occurrence, the Tyhawk operated in day and night conditions without an additional qualified watchkeeper, which was not in accordance with the crewing requirements of its safe manning document.