Investigators have found that a missing pin on a securing nut that held part of an engine in place, and problems with B.C. Ferries' docking procedures caused the Queen of Oak Bay to miss its berth and crash into a marina two years ago.
No one was injured in the June 20, 2005, accident, in which the 7,000-tonne double-ended ferry went out of control at the Horseshoe Bay ferry terminal in West Vancouver, hitting the seabed and grinding to a halt on top of 28 boats and docks as it was completing its second crossing of the day.
The Transportation Safety Board said yesterday in its report on the incident that both main engines of the 26-year-old ferry cut out about 200 metres from Horseshoe Bay. The lack of a three-centimetre-long split pin led to the disconnection of a speed governor from the fuel rack system in the first main engine, effectively causing it to fail. Since both engines are designed to work in tandem while docking, the second one shut down as well.
The master in charge noted that the ship's propellers were no longer turning and ordered the engines to be restarted. The first engine then revved out of control and triggered the second engine to do the same. This triggered a mechanism that shuts them down if they are going too fast, which in turn disabled the entire propulsion system and compromised steering, the TSB found.
The report said investigators could not determine why the split pin was missing.
Jonathan Seymour, a TSB board member, said he did not know of a similar ferry accident in the world, and that the mishap exposed a weakness in the way the Queen of Oak Bay's engines were set up.
"The way they were arranged allowed this to happen. We are concerned that a single-point failure affecting one engine has the potential to disable the entire propulsion system," he said.
Mr. Seymour contrasted the ferry's system with that of airplanes on which engines operate independently to prevent a faulty one from "dragging down another."
"We've registered [the problem]as a safety concern. One of the reasons we've done that rather than make it a recommendation is that Transport Canada has already recognized our concern and agreed with it," he said. "They are in a reform process with respect to the Canada Shipping Act and are looking at this."
Mr. Seymour said the TSB was confident Transport Canada will dictate that twin-engine ships must be made failsafe.
"That would affect any vessel that has that type of propulsion," he said.
Mr. Seymour added that the investigators also looked into B.C. Ferries' supervision and emergency-response procedures.
"We found there was a lack of supervision of safety-critical tasks and some inadequate recordkeeping. We were also concerned that it was not possible to deploy the anchor in the time available [because no one was on standby with the anchor as the ferry came into Horseshoe Bay]" he said.
David Hahn, the president of B.C. Ferries, said he welcomed the report.
"We've already taken action on almost all the report's findings. We knew most of it a long time ago; we've taken action. Our job is to embrace their findings in this particular case," he said.
However, Mr. Hahn said the cost of changing the engines as recommended by the TSB would cost $50-million per ferry and that he did not favour the idea.
He said there was no plan to replace the Queen of Oak Bay, which is considered to be in the middle of its working life.
"Our newer vessels will have more sophisticated alarm systems. I'm not saying that [the Queen of Oak Bay]is like having a character home, but they are what they are. To re-engine them and tear them apart and institute new, modern systems may have unintended consequences that may not integrate that well," he said.
One aspect of the accident that came out with the TSB report was that the Queen of Oak Bay usually docked at the No. 2 berth at the centre of the three berths at the terminal, but was directed to a different one because another ferry was occupying it.
Mr. Seymour dismissed as "speculation" the notion that this change prevented a worse accident.
Had the ferry been directed to its usual berth in the centre, it would have crashed into the terminal complex.
It wasn't all bad news for B.C. Ferries. Mr. Seymour said the TSB was encouraged by the company's swift response after the accident and the changes it has implemented.
"We've been very encouraged with what B.C. Ferries has done in response," Mr. Seymour said.
"They immediately put twice daily inspections to look at the fuel over-linkages, and they've done quite a lot of other things that would be associated with safety-management systems."
Special to The Globe and Mail
Chronology of the accident
6:24 a.m. on June 30, 2005: The double-ended ferry the Queen of Oak Bay makes its scheduled run from Horseshoe Bay, West Vancouver, B.C. to Departure Bay, Nanaimo, on Vancouver Island, without incident.8:34 a.m.: The ferry leaves for Horseshoe Bay, in slightly foggy but calm conditions, on its second trip of the day, with 544 passengers, 76 vehicles, and 36 crew members on board. During the crossing, the main engines were operating in Mode 1, and, via clutches 1A and 2B, were supplying power to the stern propeller. 10:02 a.m.: The Queen of Oak Bay arrives at Lookout Point, near the ferry terminal. 10:05 a.m.: The ferry is changed over to Mode 2, engaging all four clutches and the vessel lined up for the centre of the No. 1 berth.10:08 to 10:10 a.m.: At about 200 metres from the floating leads, all propulsive power is lost. There is a severe reduction of steerage. In the engine room, the engineers see that the clutch-control levers are still in the lock position but that the clutches have become disengaged and the No. 1 main engine has stopped while the No. 2 is still running. Alarms are triggered. The engineers try to restart the No. 1 main engine to restore power.
Repeatedly sounding the vessel's whistle, the master calls for the anchor to be deployed, but the anchor station is not crewed. The anchor is not released. The ferry hits 28 pleasure craft berthed in Sewell's Marina before running aground in the seabed. No one is injured; however, there is considerable damage to the pleasure craft and marina. After the accident: Ferry passengers are kept on board for up to six hoursCathryn Atkinson, with data from the Transportation Safety Board
Since the accident, B.C. Ferries has instituted 11 changes to its operating procedures. The most significant: Maintenance: Revised maintenance plans for the Queen of Oak Bay and other c-class vessels (those operating on the Nanaimo to Horseshoe Bay run) have been implemented. They are based on the results of a Failure Modes, Effects and Criticality Analysis (FMECA) study, which was completed in 2006. A subsequent rewriting of maintenance job plans as a result of the study is still in progress. New standards: Improve fleet-maintenance standards to more clearly specify critical systems - and the maintenance procedures to be followed for them - were completed in May, 2006. Also brought in was a new program of checklists and other standardized documentation to help keep up to date with the information. This system is currently undergoing a peer review.Daily review: The use of a daily defect review has been set up to determine if further improvements to safety can be made. This is still in progress.Testing: A fleet directive was issued regarding the trials and safety-device testing on c-class vessels, like the Queen of Oak Bay, ensuring that shutdown tests are made with engines at normal operating temperatures. As well, visual checks of fuel rack positions - which ultimately led to the accident - will be made from now on to ensure fuel shutoff occurs when needed. This system was implemented in December, 2006.Recordkeeping: Recordkeeping of the shipboard planned maintenance system was simplified in April, 2007. It is hoped this will encourage more comprehensive use by staff and contractors.
A list of some accidents involving B.C. Ferries:
Aug. 27, 2007: The Queen of Chilliwack rammed the dock at Port Harding when its propulsion system failed. Five passengers suffered minor injuries.
Jan. 9, 2007: M.V. Quinsam pulled away from the dock too soon and sent a pickup truck into Nanaimo Harbour.
March 22, 2006: The Queen of the North sank after hitting a rock off B.C.'s north coast, prompting a rescue operation in the middle of the night amid stormy weather. Two passengers were never found and are presumed dead.
June 30, 2005: The Queen of Oak Bay lost power as it entered the Horseshoe Bay terminal at West Vancouver, slamming into a nearby marina and crushing 22 boats. There were no injuries.
July 21, 2003: Four passengers suffered minor injuries when the Spirit of Vancouver Island collided with its dock at Swartz Bay. May 12, 2003: The Queen of Surrey, on a run between Horseshoe Bay and Langdale, had a diesel oil fire in its No. 2 engine. The fire was extinguished without injuries.
Sept. 14, 2000: The Spirit of Vancouver Island hit a 10-metre power boat outside the Swartz Bay ferry terminal near Victoria. Two people on the power boat were killed.
Nov. 7, 1995: The Mayne Queen crashed into a private marina on Bowen Island, damaging several moored boats.Aug. 13, 1992: Two people were killed at the Departure Bay terminal in Nanaimo when the Queen of New Westminster pulled away from the terminal as a van was driving across the ramp leading to the ship's upper deck and plunged 15 metres into the water.
March 12, 1992: The Queen of Alberni en route to Nanaimo slammed into a Japanese coal freighter shortly after leaving the Tsawwassen ferry terminal. Eighteen ferry passengers were injured.
Source: Editorial Research; Canadian Press