Ryan's Commander

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Ryan's Commander

The Ryan's Commander

The Ryan's Commander was a 65' Newfoundland small fishing vessel (NSFV) which sank as a result of the loss of stability, capsizing in 2004 off the coast of Newfoundland, Canada. The design of the vessel, as well as some of the assumptions made of the vessels apparent stability before delivery, have raised questions of ethics, regulations, and practices in light of the loss of life and the vessel itself.

Contents

Principal Particulars

Flag State............Canada
Port of Registry......St. John's, Newfoundland
Length................64' 11"
Breadth...............24'
Depth.................10' 6"
Gross Tons............149.41 t
Displacement..........115.93 LT
Centre of Gravity.....3.44 feet aft, 13.7 feet vertical (lightship)

Hullform

The hullform was typical of NSFV, with a low L/B ratio and large depth. The vessel was designed to stay below 65' and 150 gross tons (above which various restrictions and regulations begin to apply). The vessel was fitted with a bulbous bow. The vessel had little bow rake or flare, and a transom stern.

The design is an enlargement of her sister ship, the Elite Voyager. The Ryan's Commander was stretched 5 feet in length, 2 feet in width, and had her wheelhouse raised above the weather deck. The Elite Voyager had 7.5 tons of permanent ballast[1], while the Ryan's Commander had none.

Capabilities

The vessel was designed for fishing various catches. As such, it was fitted with refridgerated salt water (RSW) tanks, shrimp holds, a crab trap crane and warps/winches for working gear. The vessel was fitted with a bow thruster and anti-roll tanks.

Shelter Deck

An additional (non-watertight) deck was fitted above the main deck, running the length of the vessel. The sheltered area was fitted with spray-tight covers for working gear over the side. Atop the shelter deck was fitted a forward funnel, the wheelhouse, warp/winch, and crab crane.

Stability Factors

Regulatory

As a vessel not exceeding 24.4m (65'), 150 gt, & not fishing herring or capelin, the Ryan's Commander was exempt from the requirement to have a stability book produced & accepted, instead it was subject to Transport Canada's small fishing vessel regulations.

It is common for NSFV designs to try and avoid these regulations, most notably by fitting open shelter decks (an enclosed shelter deck would provide a level of reserve bouyancy, however the space would be included in tonnage calculations). Further, the 65' limit encourages designs to become broad & tall in order to maintain sufficient deck spaces and capacity. This tends to have a detrimental effect on tracking, and tends to raise the VCG.

Design

The vessels shelter deck, funnel, and shelter-deck mounted equipment produced a vessel with relatively high windage, particularly in comparison to its reserve bouyancy (an important counter to wind heeling moment). The weather at the time included winds of 40-45 knots, with the TSB report noting differential heeling (10 degrees port, 24 degrees starboard), beam wind and seas, and two rolls of atleast 35 degrees prior to capsizing.

The vessels transom stern and straight lines aft imply poor tracking in following seas, with poor flow reconciliation into the propeller and rudder, and a poor ability to part overtaking waves; the result is lowered rudder response, lower power delivery, with 'lifting' and rapid changes in buoyancy in the aft of the vessel due to wave action. While the true implications of the stern design would require model testing to verify, poor handling was listed by the TSB as a critical factor in the vessels loss.

Anti-Roll Tank

The anti-roll tank was mounted high on the shelter deck, with 280mm of water in the tank. The TSB reports neither of the tanks dump valves had been operated. When subject to a continual list, the water in an anti-roll tank will collect on the lower side (into the list), exasperating the vessels list condition. Tanks are maintained in a slack condition, producing a free surface effect (which resists roll when the roll period and tank level are correct, but can be detrimental outside the design range). In non-ideal situations, it is generally safer to dump the anti-roll tank contents to lower the VCG and decrease the FSE.

Loading

At the time of departure, a damaged trawl net was stowed atop the shelter deck, and the vessel carried a full compliment of crab equipment. Watertight doors in the vicinity of the RSW tanks had been removed.

Prior Stability Analysis

After construction, the vessel was subject to sea-trials in winds up to 20 knots and a brief inclining test. At the time, the vessel appeared to have sufficient stability. The inclining test seemed to generate a relatively high GM as well. This inclining test, however, lacked rigor. The TSB report also indicated the vessels initial stability, up to 19 degrees, generally exceeded the stability requirements. This may have proved misleading, as the vessel would not demonstrate a regulatory stability deficit until beyond heel angles of 24 degrees. The Ryan's Commander may have also suffered from comparisons to her sister ship (commonly done, see lightship survey). The Elite Voyager was fitted with 7.5 LT of ballast (nearly 8% of her displacement), which would produce a noticeable drop in the VCG. If this is not accounted for (i.e., during a weight estimate or lightship comparison) it could skew the comparison.

Transport Canada Report

The Transport Canada report describes the vessel as having a steady heel to port of 7 degrees (asymmetrical roll) induced by wind prior to the sinking. A combination of the wind heel, combined with wind gusts and beam seas, are attributed for pushing the vessel outside its range of stability. The vessel washed ashore & broke up.

Aftermath

The vessel sank with the loss of 2 brothers. The family of the brothers sued both the Federal government (for failing to ask for adequate crew training [2]) and the builders (challenging the design as unsafe). The lawsuit has not yet been resolved. As of July 31, 2009, the Supreme Court of Newfoundland has overturned a Workers Health & Compensation ruling against the lawsuit[3], which the families lawyers stated was crucial to the lawsuits continuation[4].

A review of fishing vessel safety was also conducted by Transport Canada[5], which is expected to be released in the fall of 2009[6], though some recommendations (such as the submission of stability data for all fishing vessels), have already been made [7]. A seperate independent review is being conducted by Memorial University[8]. The Department of Defense included this incident in an investigation of Search & Rescue responses[9], which calls for better boat safety.

A book on the incident was wrote by a sister of the two lost brothers, Johanna Ryan Guy, entitled Ryan's Commander: The Boat That Should Not Have Sailed.

External references

  • Transport Safety Board of Canada report [10]
  • Ryans Commander: The Boat That Should Not Have Sailed [11]
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