Overspeed Protection Alarm Causes Ship’s Engine to Stop


On 4th of December 2016, the German-flagged Hanni ran aground in Hamburg. The master and chief officer were on the bridge. An overspeed protection alarm was issued for the main engine. After that, the main engine reduced the revolutions and finally stopped. 

The incident:

The same day, the bosun was instructed to operate the anchor. A few minutes later the vessel FINJA and avoided collision by little, setting the rudder to hard to starboard. After the main engine’s control system was switched to the engine control room.

Hanni then drifted to the other side of Elbe. More engine alarms sounded, including the shaft generator. The ship lacked its main engine, something that means that the vessel was not in control for a long time and only its momentum made the steering possible.

Hanni’s speed over ground stood zero and as a result she was grounded to the other side of the fairway. The vessel’s traffic service indicated the accident on a VHF channel.

After the traffic service informed about the accident, two tug boats, Rasant and Prompt attempted to salvage Hanni. Their first attempt was not successful, but the second attempt a few hours later was.

No injuries of personnel or pollution were noted after the accident.

Probable cause:

Germany’s Federal Bureau of Maritime Investigation stated the accident happened because an overspeed protection alarm made the main engine to stop automatically, in order to avoid irreparable damage. The alarm went off due to a defective pick up.

Hanni drifted to the other side of the fairway, because of hydrodynamic forces.


Germany’s Federal Bureau of Maritime Casualty Investigation proposed to Hanni’s owner the following:

  • To include the pickups and speed sensors in a maintenance plan and take precaution in exchanging them on vessels, in compliance with values suggested by the manufacturer.
  • To revise the wheelhouse poster and the pilot card, complement all queried data and include CPP’s direction of rotation.

Furthermore, the master of the ship was instructed to change the underway watch schedule so that officer are not on watch more than ten hours.

Moreover, the Federal Bureau of Maritime Casualty Investigation recommended the engine manufacturer, MAN Diesel and Turbo, to configure the main engine’s pickups, in order for plausibility check to be made between the sensors.

Did you subscribe for our daily newsletter?

It’s Free! Click here to Subscribe!

Source: BSU


This site uses Akismet to reduce spam. Learn how your comment data is processed.