Can Technology Help Stability?

 maritime safety news  Comments Off on Can Technology Help Stability?
Jan 282013
The Stabilicube

The Stabilicube

So your GM is good, your GZ areas exceed the required minimums, you’re all set for a safe passage, right?

Not necessarily. Your calculations may become invalid once you cast-off because stability is a moving target.

There are dynamics at work on your vessel, a mechanism that depletes stability reserves in a dynamic process whereby energy is gained from the wind and waves.

A ship underway at sea has energy on all six axes of motion and there are energy exchanges between these axes. The 6 axes are pitch, roll, heave, sway, surge, yaw.

For example energy on the yaw axis can build until directional control is lost, rudders and thrusters become ineffective. Continue reading »

Heather Anne – “No Lifejacket Fatality/Roll-Tests May Not Tell Stability Story

 Accident, Accident report, capsize, maritime safety news, Sinking  Comments Off on Heather Anne – “No Lifejacket Fatality/Roll-Tests May Not Tell Stability Story
Jan 272013
Recovering Heather Anne. Stability tests 'misleading'

Recovering Heather Anne. Stability tests ‘misleading’

Britain’s Marine Accident Investigation Branch, MAIB, has warned that roll-tests may give a misleading assessment of vessel stability in its accident investigation report on the capsize of the fishing vessel Heather Anne. It has also called for the Maritime and Coast Guard Agency to determine what behavioural changes are needed to ensure that fisherman wearing lifejackets on deck.

At about 2200 on 20 December 2011, the UK registered fishing vessel Heather Anne capsized and foundered in Gerrans Bay, Cornwall. The skipper and his crewman were soon recovered from the water by a nearby fishing vessel. Neither the skipper nor the crewman was wearing a lifejacket; the crewman had drowned. There was no significant pollution.

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Tankers Get The Paris Touch

 maritime safety, Paris MOU  Comments Off on Tankers Get The Paris Touch
Aug 022010

image The Paris Memorandum on Port State Control starts a concentrated inspection  campaign, CIC, to verify correct damage stability on oil tankers, chemical tankers and gas carriers from 1 September to 30 November 2010.

Says the ParisMOU: “The reasons for this CIC include that inspections showed tankers frequently sailing when not complying with damage stability requirements or had no means of assessing damage stability or were sailing in a loading condition not covered by the approved stability book.

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Lessons From Aquila Triple Fatalities – Check Your Mods Professionally

 Accident, Accident report, capsize, fishing, MAIB, Safety Alerts  Comments Off on Lessons From Aquila Triple Fatalities – Check Your Mods Professionally
Apr 162010

Scalloper Aquila - Ballast had been modified

Planning to add ballast or make other modifications to your vessel? Get a competent person to check the effects on stability, says a safety flyer for the fishing industry from the UK’s Marine Accident Investigation Branch, MAIB. Also make sure that the risks of fishing gear becoming snagged, particularly when trawling downwind, are fully assessed to ensure appropriate control measures are in place to prevent water ingress or capsize.

The safety flyer comes in the wake of MAIB’s report on the capsize of the scallop dredger Aquila after she became snagged on the seabed while trawling, downwind, in moderate to heavy seas near the isle of Eigg.

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