The stern rudder presents a formidable challenge to the power of the sea. Already extant by the twelfth century in the Frisian region, it has long been compared with the quarter rudder of antiquity. Past scholarly studies have focused almost entirely on the reasons for its creation, ignoring the complex evolution of this steering system. The disastrous consequences of the rudder's loss mid-voyage made its replacement necessary, although this was a last resort. Through a close analysis of the printed sources, the article considers the attempts of the English and French navies to incorporate emergency and spare devices on board. The present review reveals the importance of the stern rudder to seafarers and the means undertaken by these two naval forces in order to find substitutions in the event of damage to the initial rudder.