Over a century has passed since the Endurance, reputedly the strongest wooden ship ever constructed, met its fate in Antarctic ice. Recent evaluations of historical evidence indicate that it might not have been as resilient as other polar vessels of its era, casting doubt on expedition leader Ernest Shackleton’s awareness of its limitations.

Shackleton aimed to journey across Antarctica from the Weddell Sea to the Ross Sea, making stops along the way. However, the Endurance never reached the Antarctic coastline. In 1915, it became trapped in ice in the Weddell Sea, leading to its sinking.

Jukka Tukuri, who was part of a significant expedition at Aalto University in Finland, discovered a shipwreck on the seabed in 2022. Upon researching the polar vessels of that time, he found that the narrative surrounding the Endurance was misleading; it lacked the structural strength attributed to it.

During the late 19th and early 20th centuries, several ships were engineered specifically to navigate sea ice. Many featured an oval hull shape and shallow keels, which helped prevent ice from creating strong hold on the side, allowing it to slide beneath. Additionally, the internal structure of these vessels included a continuous deck spanning the hull’s entire length, which enhanced their rigidity.

In contrast, the Endurance was longer and had taller keels. Tukuri’s calculations indicated that other contemporary polar ships could withstand 1.7 to 2.7 times more compressive force than the Endurance. Furthermore, the ship’s large engine restricted the lower deck to only part of the vessel, creating structural weaknesses due to the absence of a reinforced box-like configuration.

In his review of Shackleton’s letters, Tukuri found evidence that Shackleton was aware of these design flaws. Just before departing for Antarctica, Shackleton noted in a letter to his wife that Nimrod, his previous ship, was more robust. Yet, he pressed on with his journey: “He was willing to embrace the risk,” Tukuri commented.

As predicted, the Endurance could not withstand the immense pressure of the sea ice. The vessel was compressed and distorted until its keel was ultimately torn apart and submerged.

Despite this, a myth arose portraying the Endurance as the world’s most resilient wooden ship, potentially fueled by an article in The Era. According to Tukuri, Shackleton perpetuated this narrative; the reasons remain unclear, but it seems to add an element of drama to his ill-fated expedition. “Endurance may have symbolized strength and heroism poetically,” he said. “Regrettably, that was not the case from an engineering perspective.”