How can we aim for better steering?

摘要

Q I purchased our boat moon river last autumn and am not a novice. At low revs it will not respond to the steering (coming into locks when we are being considerate of others), however, at normal cruising revs it is lovely. The boat is steel, 34ft long with an 11ft beam. The rear cabin was attached at a later date, years after construction. The prop is approximately 4ft from the stern and the rudder is aligned with the prop. The engine is a Ford with plenty of power. There is a bathing platform attached to the stern.