It’s complicated and difficult, but they keep coming back because, said one, ‘it’s the hardest.’
In sailboat racing, the fastest route between Port A and Port B is rarely a straight line.
This is certainly true of the annual Rolex Sydney Hobart Yacht Race, which starts on Monday. This classic test of seamanship and teamwork involves many complex navigational decisions, including negotiating the course’s mix of coastal and offshore waters, its fast-moving westerly weather fronts and the generally south-flowing East Australian Current.
Navigators invest huge amounts of time and bandwidth before and during the race, leveraging navigation tools and experience to determine how weather and current will affect the course’s challenges.
Lindsay May, who has served as navigator or skipper on boats that have won the race’s top trophy, the Tattersall Cup, three times, described the race’s 628-nautical-mile track as six navigational tests. There’s the start and the sprint out of Sydney Harbor, past the Sydney headlands; the run down Australia’s coast; crossing Bass Strait, which separates Australia from Tasmania; the stretch down Tasmania’s eastern coastline; the crossing of Tasmania’s Storm Bay; and the final leg up the River Derwent.
Bungle any of these and a team’s results can go south, fast.
In addition, teams sometimes elect to sail extra miles to reach faster or safer conditions, or sacrifice mileage for tactical positioning relative to the fleet. “You invest those extra miles sailed with the expectation that you’ll get a return on them,” said Stan Honey, an America’s Cup and Volvo Ocean Race-winning navigator who helped LDV Comanche set the race’s elapsed-time record in 2017. “The job of the navigator today is making these risk-adjusted investment decisions.”
Getting this right — or less wrong than the competition — demands that navigators possess world-class meteorological and technical skills to select the fastest course for their yacht.
This isn’t trivial.
“The mixture of the East Australian Current, the coastlines of New South Wales and Tasmania with Bass Strait in between, then Storm Bay, and then finally the Derwent River make the racecourse a real navigational-meteorological challenge,” said Will Oxley, a navigator who has also won the Tattersall Cup three times, and who plans to navigate the 100-foot Andoo Comanche (previously LDV Comanche) in this year’s race.
Weather is notorious in the Sydney Hobart. From 1945 to 2021, the race had an average attrition rate of 15 percent. In 2021, 38 yachts out of the race’s starting fleet of 88 retired, many because of equipment or vessel damage.
“The navigator’s role now is largely about weather and strategy, and it’s very much now electronically driven,” said Adrienne Cahalan, a two-time Tattersall Cup-winning navigator who plans to start her 30th race aboard the 39-foot Sunrise this year.
Local knowledge can also be important. “Just because of having lived and breathed the weather systems in this country, that will give you an advantage,” Cahalan said.
So will modern navigation tools. These include computers, software and lots of data.
Before yachts even leave the dock, navigators leverage these tools and information from the yacht’s instruments, its designer and handicap-rating systems (think golf), to create vessel-specific models called polar diagrams.
These predict how fast the boat will sail at different wind angles and velocities. Navigators then use digitized weather and current forecasts — called gridded binary files or GRIBs — which are prepared by official meteorological services. Navigators also use the yacht’s polar diagrams and performance information about each of its sails to advise the skipper on which ones to bring.
Navigators rely on the yacht’s satellite-communications equipment to continually download GRIBs as different models are released. These are fed to computers running weather-routing software to help determine the fastest route based on a specific yacht’s polar diagrams in the forecasted conditions.
Navigators game out multiple routing options based on the latest GRIBs and their yacht’s position relative to the competition.
“In the 2019 Sydney to Hobart race, there was a split breeze in Storm Bay,” Oxley said. “The high-res GRIB files did not show this perfectly, but they did provide strong evidence that it existed.” The team chose a route on the west side of Storm Bay, rather than taking the more standard routing. “This paid off and we managed to win,” he said.
This analysis is critical for making the most important decisions. For Honey, who plans to navigate the 100-foot Hamilton Island Wild Oats this year, these include making calls on how far offshore to sail after passing the Sydney headlands, how to handle the East Australian Current, how close to Tasmania to sail and how to approach Tasman Island.
Even with the polar diagrams, up-to-date meteorological data and weather-routing tools, human expertise still matters.
“The global met models do a great job these days in managing the big picture,” Oxley said. “Where they fall down is in managing the fine detail and dealing with land shadows and breezes.”
“If the forecast is wrong, it won’t be entirely wrong, but it will be wrong by being too fast or too slow, or windy or too light,” Honey said. “You have to think through what kind of characteristic errors you expect to see in the different forecast models, and that’s just experience.”
And it’s also where eyeballs can supersede screens.
“It is important to get your head out of the boat and look around,” said May, who plans to start his 49th race this year aboard the 74-foot Kialoa II. “The art of navigation is to be aware of the science, but the same time use your experience and see and sense what is happening.”
This often entails studying the clouds and sky, and peering between the lines of GRIB data.
“I do believe that intuition and gut feeling is an important part of decision making,” Cahalan said. She added that while contemporary weather modeling was clever, humans still needed to assess what the data presents.
“That’s the experience that you bring to the team, that’s where you bring value,” she said.
Wind whispering aside, navigators must also foster trust with the team’s brain trust.
“For me, the best system is where I spend a lot of time before the race laying out the plan with the whole crew, and especially the key decision makers, and then working to execute the plan,” Oxley said. “I always benefit from watch leaders asking questions and probing my recommendations to improve the final decisions.”
Crew knowledge also matters. Honey said he briefed the on-deck crew every two or three hours. “The better they understand it, the better they’ll sail,” he said, adding that this helps the sailors negotiate gusts, lulls and unexpected squalls.
Communication is especially important if a strategic move that results in a short-term loss of position is made for better position later, or when decisions are not obvious. “I make it clear whether I am 90 percent strong on a recommendation, or whether it is closer to 50-50,” Oxley said.
And in the Sydney Hobart, jump-ball calls can apply until the finish line.
While most of the race’s miles involve exposed coastal or offshore sailing, the out-flowing River Derwent stands as the race’s final crux.
May described the Derwent as miles of frustration, a time when navigators need to play their lucky cards. Arrival time is crucial. Most afternoons and evenings feature a useful breeze, while most nights are calm. “Light winds will only allow you to ghost along the shore, keeping out of the adverse current,” May said of nighttime arrivals.
Cahalan added that many races had been won and lost in the river.
Add up the race’s variables, coupled with its attrition rate, and there’s little question why this race attracts world-class navigators, who keep returning.
“It’s just so complicated and so difficult for the navigator,” Honey said. “It’s my favorite race because it’s the hardest.”