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.

船尾舵对海洋的威力提出了巨大的挑战。它已经存在于十二世纪的弗里斯兰地区，长期以来一直与古代的四分之一舵相提并论。过去的学术研究几乎完全集中在其创建的原因上，而忽略了该转向系统的复杂演变。尽管这是不得已的方法，但由于舵在航行途中损失而造成的灾难性后果使得有必要进行更换。通过对印刷资料的仔细分析，本文考虑了英海军和法海军的尝试，将应急装置和备用装置整合到船上。本篇评论揭示了船尾舵对海员的重要性以及这两个海军部队为在初始舵受到损坏的情况下寻找替代品所采取的手段。