Stability Decay

Did you know that a perfectly stable vessel can become unstable and useless?  Understand how stability decay affects your vessel life.

I knew a ship owner with an old boat that was perfectly functional.  After a USCG inspection, the owner was suddenly forced to do a completely new stability test for the vessel and create a whole host of new documentation.  Why?  The owner suffered from stability decay.

Stability decay:  dreaded words.  Did you know that a perfectly stable vessel can become unstable and useless?  Its insidious.  It slowly creeps up and destroys the vessel stability.  In this video, I cover the three essential things you need to know for stability decay.

• What creates stability decay.
• How to control stability decay.
• How to prevent and reset stability decay.

Stability decay comes from weight changes to the ship.  These weight changes can be summarized as three basic rules to remember.

1. All ships change weight as they age.
2. These changes usually raise the vertical center of gravity (VCG) and reduce stability
3. Small weight changes add up.

So how can you control these weight changes?  The best prevention is recording the weight changes.  You need to maintain a written records of any permanent weight changes to the vessel.  Record the following items.

1. Date of weight change.
2. Weight change (weight removed, added, and amount).
3. Center of gravity for weight.
4. Brief description of what changed.  Something like:  installed new radar, removed old radar.  Or:  renewed antifoul paint.

Why should you record these weight changes?  They give you control and allow you to predict when you will need a new stability test.