Row2Rio rower Zirk Botha
The 59-year-old rower Zirk Botha, who is currently making a voyage from Cape Town to Rio de Janeiro, was just off the coast of St Helena island on January 11, making his way toward crossing the Greenwich meridian line.
January 11 marked the twenty-fourth day of his three-month journey in support of the environment and sustainable development.
The Trans Atlantic crossing requires him to row completely unassisted for about 90 to 100 days, over about 7 000 km, or 3 800 nautical miles, in difficult weather and sea conditions.
He has completed about 2 500 km, or 1 350 nautical miles, so far.
Botha says he is a week ahead of his originally anticipated schedule, and should sea conditions not prove more challenging, he could complete the row in under 100 days.
Botha, who is being sponsored by renewable energy company Juwi, says he did a great deal of research on his route, as well as on finding a weather window, considering that wind direction was key.
His voyage is informed by a historical maritime practice going as far back as when Vasco Da Gama was travelling the seas. Da Gama used trade winds to his benefit. The same route and similar timing have been used during the Cape to Rio yacht race.
Botha opted to use a closed cell foam open class design ocean-rowing boat designed by esteemed naval architect Phil Morrison.
The current norm for ocean rowing boats is to be built from marine plywood or in a fibreglass and epoxy mould. However, Morrison’s design uses closed cell foam laid up with fibreglass and epoxy resin.
The specific design incorporates honeycomb construction principles, which ultimately makes it strong yet lightweight. The boat is constructed like a life boat to self-right, meaning the boat will roll back upwards in case the boat is tipped in extreme weather.
The boat is 6.5 m long, with a 1.62 m beam and weighs about 550 kg, including all equipment, spares and food loaded. The boat is powered by two 12 V batteries connected in parallel with a combined 200 aH capacity.
These are deep cycle batteries used for charging with solar panels. Botha opted to use Solbian flexible solar panels, with a peak capacity of 276 W at 46 V.
The boat also has a desalinator fitted on board that provides fresh water for the rower, making up to 16 ℓ of fresh water an hour, while the boat is also fitted with three electric bilge pumps and a manual hand bilge pump in the event of a flood.
Botha can communicate through a very high-frequency radio equipped with a global positioning system, automatic identification system (AIS) and digital selective calling (DSC) facility. The AIS allows Botha to get early warnings of ships in his vicinity, while the DSC allows Botha to communicate with them.
Additionally, Botha has a satellite phone that is charged by lighter socket or USB.
Botha served 17 years in the South African Navy, during which time he completed three Atlantic crossings.