When the wreck of Ernest Shackleton’s ship Endurance was found nearly 10,000 feet below the surface of Weddell in Antarctica. sea in March 2022, it located only 4 miles from last known positionas recorded by the captain and navigator of the Endurance, Frank Worsley, in November 1915.
That’s an amazing level of accuracy for a position determined using mechanical devices, book-length tables of reference numbers, and pen and paper.
The ship-finding expedition searched the undersea area of the 150 square kilometers – a circle 14 miles wide. No one knows how accurately Worsley’s position was calculated, or how far the ship traveled while sinking.
But as a historian of Antarctic explorationI wasn’t surprised to learn how accurate Worsley was, and I imagine those looking for the wreck weren’t either.
Navigation is key
The Endurance left England in August 1914, with Irishman Shackleton hoping to become the first crossed the Antarctic continent from one side to the other.
But they didn’t even land in Antarctica. The ship became stuck in sea ice in the Weddell Sea in January 1915, forcing the men to disembark into tents pitched on the frozen sea nearby. The force of the ice slowly crushed the Endurance, sinking it 10 months later, and began what would become a remarkable – and almost unbelievable – saga of survival and navigation for Shackleton and his crew.
Shackleton’s own leadership was done stuff of legendas he was committed to making sure that not a single person was missing from the group under his command – though three members of a 10-person Ross Sea expedition team destroyed.
Less well known is the importance of the navigation skills of 42-year-old Worsley, a New Zealander who has spent decades on British Merchant Navy and the Royal Navy Reserve. Without him, the story of Shackleton’s survival might have been very different.
Time to mark
Navigation requires determining a ship’s location in latitude and longitude. Latitude is easily found from the angle of the Sun above the horizon at noon.
Longitude required compare to local noon – the time when the Sun is at its highest point – with the actual time at another location where the longitude is known. The key is to make sure the time measurement is accurate for the other location.
Making these astronomical observations and making the resulting calculations is very difficult on the ground. At sea, with few fixed points of land visible, in the midst of bad weather, it is almost impossible.
So navigation is largely dependent on “dead reckoning.” This is the process of calculating a ship’s position using a previously determined position and incorporating estimates of how fast and which way the ship is moving. Worsley calls it “the seaman’s calculation of courses and distances.”
Wanting the land
When the Endurance was crushed, the crew had to find their way to safety, or die on an ice floe drifting somewhere in the Southern Ocean. In April 1916, six months after the sinking of the Endurance, the sea ice where they were camped began to break up. The 28 men and their remaining tools and equipment loaded into three lifeboats – James Caird, Dudley Docker and Stancomb Wills – are each named for major donors to the expedition.
Worsley was in charge of landing them. as the journey beginsShackletonsaw Worsley, as navigation officer, balancing himself on the gunwale of the Dudley Docker with his arm around the mast, ready for the sunset. He got his observation and we waited anxiously as he rehearsed the scene.
To do that, he compared his time measurement with his chronometer and written records of calculations.
A last hope for survival
When they reached a small rocky strip called Elephant Island, off the coast of the Antarctic Peninsula, they were still facing starvation. Shackleton believed that the only hope of survival was to get help from elsewhere.
Worsley is ready. Before Endurance was crushed, he had “works on courses and distances from the South Orkneys to South Georgia, the Falklands and Cape Horn, respectively, and from Elephant Island to similar places,” he recalled in his memoir.
The men used parts of other lifeboats to strengthen the James Caird for a long sea journey. Every day, Worsley”carefully observed the sun or stars to appearon correcting my chronometer, on the accuracy of our lives and the success of the journey will depend.”
On April 24, 1916, Worsley obtained the “The first sunny day with a clear horizon to get a view for rating my chronometer. ” That same day, he, Shackleton and four other men sailed under the sail of the 22.5-foot James Caird, which carried Worsley’s chronometer, navigational books and two sextants, which were used to fix the position of the Sun. and the stars.
The boat trip
These people, in this little boat, set off from one pinpoint of rock in the Southern Ocean to another, facing strong winds, strong currents and rough waters that can push them astray or even sink. The success of this journey depended on Worsley’s absolute accuracy, based on the observations and estimates he made in the worst possible environmental conditions, while sleep-deprived and freezing.
They spent 16 days in “supreme strife among the raging waters,” as the boat sailed through some of the most dangerous sea conditions in the world, experiencing “mountainous” downpours, rain, snow, hail and hail. That time, Worsley did the right thing four strong fixes in the position of the boat. Some are “a happy mockery of guesswork” to know where the wind and waves are taking them, and adjust the steering accordingly.
The stakes are high – if he misses South Georgia, the next land is South Africa, 3,000 miles away across the more open seas.
As Worsley later wrote:
“Navigation is an art, but words fail to give my efforts a proper name. … Once, perhaps twice, in a week the sun smiled in a sudden flash of winter, through a storm-tossed cloud. If ready for it, and smart, I got it. The procedure was: I looked out from our hole – precious sextant hugged under my chest to prevent the seas from falling on it. Sir Ernest stands under a canvas with a chronometer, a pencil, and a book. I shouted ‘Stand by,’ and knelt on the barrier – the two men on the other side grabbed me. I sent the sun down to where the horizon was and as the boat leaped very fast up the top of the wave, guessed the height well and shouted ‘Stop.’ Sir Ernest took the time and I worked on the result. Then the fun begins! Our fingers were so cold that he had to translate his trembling numbers – my own so illegible that I had to recognize them through the works of memory.
On May 8, they saw floating seaweed and birds, and then saw land. But they arrived in South Georgia in the middle of a storm, and for two days had to fight being driven by the wind to an island they had spent weeks desperately trying to reach.
Finally, they arrived at the beach. Three of the six men, including Worsley, trek across uncharted mountains and glaciers to reach a small settlement. Worsley joined the rescue boat to retrieve the other three. Shackleton later arranged for a ship to collect the other men from Elephant Island, all of whom survived. their own unimaginable difficulties.
But the key to all of this, and indeed the new discovery in the destruction of the Endurance, is how Worsley fights in desperate situations and many times knows where they are, where they are going and how to get there.