Understanding the stability of your vessel will help keep you and your crew safe. Capsizing due to insufficient stability is a major cause of fatalities for fishing vessels, especially those under 15m.

There have been some high-profile vessel and life losses recently due to poor vessel stability. Know your limits. Check the stability of your vessel.

“I would definitely recommend the roll test. It’s really easy, and it’s not going to take you very long.”

Ashley Mullenger, whelk fisherman, Wells-next-the-Sea.

Benefits of checking your vessel’s stability

  • Vessel stability is complex and influenced by different factors, changing continuously when at sea and throughout the vessel’s lifetime. Regular checks mean you can identify potential issues before you go to sea.
  • Your vessel must pass a stability test to get your fishing vessel certificate and give you the information to operate your vessel within its safe limits. 

Top tips

  • Your vessel will be required to take a stability test. The type of test depends on the vessel. Read MGN503 to find out which test you need.
  • Make sure you’ve performed a stability test (roll or offset load test) on your vessel so that you have a good idea of your vessel’s stability before your inspection. These tests are simple to do. Watch the videos to see how. 
  • Always seek the professional advice of an expert before making modifications to your vessel as this can affect its stability.
  • Be aware of your vessel’s loading recommendations. The overloading of fish can reduce the freeboard and raise the centre of gravity, which may reduce the vessel’s stability and increase the risk of it capsizing.
  • Make sure you understand the principles of the free surface effect and how to prevent it from happening on your vessel.
  • Take caution when hauling, as this can alter the vessel’s centre of gravity and increase the risk of capsizing. The lower the hauling point, the lower the risk of capsizing.
  • Stability Awareness training courses are available for all levels and experience. These are highly recommended and also a requirement for the Under 16.5m Skippers Certificate.

Watch more safety videos

Do you know the point of no return?

Watch the animations below to understand the main causes of instability in fishing vessels:




Free surface effect

Safety tips from fishermen

Ashley Mullenger, whelk fisherman from Wells-next-the-Sea tests the stability of her vessel Saoirse.

MCA surveyor Roger Gee takes us through how to do a roll test to assess the stability of a fishing vessel.

The Seafarers’ Charity

Charles Blyth, NFFO Risk, Safety and Training Lead, discusses stability basics.