Weather Helm

A sailing vessel’s tendency to turn towards the wind unless opposed by helm or trim.

Weather helm arises from the relationship between aerodynamic force, underwater lateral resistance, heel, hull asymmetry and rudder angle. A small tendency can provide feedback and make the vessel round up if steering is released, but excessive weather helm increases drag and can overload or stall the rudder.

Sail balance, reefing, traveller and sheet settings, mast rake, centreboard or keel configuration and weight distribution can alter it. A sudden increase may also indicate a gust, excessive heel, damage or loss of steering effectiveness rather than a routine trim issue.