200868 Controllable pitch propeller systems

Official report: abridged from USCG Alert No. 3-2008

A recent marine casualty involving a large fishing vessel resulted in multiple fatalities and loss of the vessel. Based on the survivors' testimony, the crew experienced difficulty with launching and entering the three liferafts because the vessel was making considerable sternway when the order to abandon ship was issued. Evidence indicates the main engine was still running with the propeller remaining in astern pitch. Consequently, two of the liferafts quickly drifted past the bow of the vessel soon after they were launched. Attempts to retrieve the liferafts using the painter lines were unsuccessful.

As a result, most of the crew members were forced to jump into the near freezing water and attempt to swim to the liferafts. Ultimately, only 22 got into the liferafts. All these crew members survived. Of the other 25 who never made it into a liferaft, four died and one remains missing.

The Coast Guard strongly recommends that owners, operators, and masters of vessels with controllable pitch propellers (CPP) understand the design and operation of the system. This includes the primary and emergency sources of power for both the control and main systems, the location and procedures for using alternate control stations, and the locations of the emergency shutdowns. While controllable pitch propeller systems are generally designed and constructed to fail in the 'as is' position, in hydraulic CPP systems, the actual blade pitch may change. In this case the vessel was making considerable sternway.

In light of this incident, vessel owners, operators, masters and crew members should also be mindful of the following safety issues:
Shipmasters and officers must maintain situational awareness at all times and understand the effects of their actions and decisions on the safety of their crew, especially during emergency situations involving flooding. This includes understanding what impact the vessel's speed, heading, heel, and trim will have on the crew as it abandons ship.
The master or individual in charge must evaluate the particular circumstances of each emergency situation (weather, seas, experience of crew, condition of vessel etc) and adjust emergency procedures accordingly to provide for the safety of the crew, vessel, and the environment.
All crew members should understand that immersion suits will affect their dexterity, limit mobility, and may make it more difficult to launch survival craft, particularly when the survival craft are covered with snow or ice. Crew members responsible for launching the survival craft should practise and be able to launch with their immersion suits on. Lifesaving gear should be kept free of ice and snow whenever possible.
When abandoning ship, crew members should make every effort to enter directly into a liferaft or lifeboat before entering the water. If crew members must enter the water, they should stay together and attempt to enter a liferaft, climb on to floating debris, or use any other means available to get themselves out of the water as soon as possible.
Emergency drills should not be limited to routine procedures such as donning immersion suits. Emergency drills should ensure all crew members, including bridge and engine room personnel, understand and practise what to do in various emergency situations under actual conditions. Additional information regarding emergency procedures for commercial fishing vessels can be found at: http://www.fishsafe.info