The last thing he needs is wind-whipped eyes while trying to follow the directions indicated by "the silly bugger who sits next to me" - his Glenorchy navigator, Pete Reid.
"I'm boating the water directly in front of me and he is looking ahead and picking the channels."
The pair will be giving Williamson's new boat its first long-distance outing when they compete in the six-day world jet-boat marathon beginning on Sunday.
The Eagle 6.5m race hull was purchased from Canada "purely on the back" of their New Zealand marathon result last year, when they finished second in their debut race season.
With the design shape of its base providing superior speed and handling, coupled with the imported turbine jet unit running "pretty much the latest technology from America", Williamson is feeling confident.
"I think we've got a pretty good package there to give us as good a chance as anyone else to get a world title."
Dart Engineering owner Williamson (33) said his team had already had a "wee marathon on our own" getting the boat ready in two and a-half weeks to enter a short shakedown event on the Waitaki River.
His silver-flame emblazoned racer will be one of 14 entered in the marathon's unlimited class and will cover between 100km and 150km a day.
"It's hard on the body and hard on the mind. You get quite fatigued."
His boat is powered by a 572 big block Chev engine, but Williamson insists it has a "reasonably modest" 750hp.
"Some of the boys will be running 1000 to 2000 horsepower."
An example of a fast crew is the United States team led by Ryan Ringer, which event organiser Jeff Horne believes has entered arguably the fastest marathon-style racing jet boat in the world.
"Their Eagle boat is powered by a Hughes 500 helicopter gas turbine engine and is reputedly capable of achieving speeds in excess of 130 mph [209kmh]," he said.
Williamson will also be racing against New Zealand's multiple world champion, Mark Cromie, of Whangarei, whose jet-boat holds the New Zealand speed record.
Racing for the 34 entries begins on Sundayon the Waimakariri River and finishes there the following Saturday.
The six days of racing - there is one rest day - will encompass the Waiau, Rakaia and Waitaki rivers, with Wednesday providing the best viewing opportunities for North Otago residents.
The competitors will race along the Waitaki River from the State Highway 1 bridge to Kurow and return.
Jet Boating New Zealand Otago branch member Pete Templeton said spectators could catch the boats flying by at the irrigation intake below Duntroon on the south side and from the stone wall on the north side, above Ikawai.
