594 - 8/08 - Controllable Pitch Propeller Systems & Situational Awareness - Worldwide


A recent marine casualty involving a vessel in the Bering Sea resulted in multiple fatalities and complete loss of the ship. Although the subsequent investigation is not complete, safety issues associated with casualty have been identified that merit immediate public dissemination.

Based on the survivors’ testimony, the crew experienced difficulty with launching and entering the three liferafts because the ship was making considerable sternway when the order to abandon ship was issued. Evidence indicates the main engines were still running and the ship was backing with significant astern pitch.

Consequently, two of the liferafts quickly travelled forward past the bow of the vessel when they were launched. Attempts to retrieve the liferafts using the painter lines were unsuccessful. As a result, the majority of the crew members were forced to jump into the 34°F water and attempt to swim to the liferafts. Ultimately, only 22 members of the ship’s crew made it into the liferafts. All of these crew members survived. Of the other 25 crew members who never made it into a liferaft, four died and one remains missing.

In Marine Safety Alert 3-08, the United States Coast Guard strongly recommends that owners, operators, and masters of vessels with controllable pitch propellers 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. This was not a unique occurrence. The MS EXPLORER also experienced this problem before it sank in November 2007. Vessel operators, masters and crew members must be prepared to respond accordingly.


Staff Author