Sail in Irons

This spell can only be used when an enemy ship attempts a turn. The spell causes the target vessel to lose inertia when coming about so that it stops with its bow pointing into the wind, which renders its sails useless. The ship remains in irons for a minimum of one round per caster level. The captain of the target vessel receives a saving throw vs. spells for one-half effect. In addition, the captain of the enemy vessel must make a navigation or seamanship proficiency check to get the ship moving again, once the spell expires. Putting an enemy ship’s sail in irons is something of a coup and will cause the enemy sailors to curse and swear heavily.

The material component (consumed) is a link of heavy iron chain worth not less than 1 gp.