A Tauranga entry in the Bridge to Bridge Water Ski Classic this weekend is going to turn heads because of its sound.

Alongside the piston engined competition in the 82km long race is the jet engine powered boat Dean Landon has built for Mark Cromie.

The Canadian built Eagle alloy hull is powered by a General Electric T58 gas turbine.

When the jet was started this morning its noise drew a crowd of onlookers from nearby businesses (pictured). A second start-up demonstration is today at 4pm at Steve's Marine Supplies at Sulphur Point.

It is a helicopter jet engine, more commonly found in Sea King helicopters, like the one flying over Tauranga recently while engaged in the Rena salvage.

It produces about 1450hp, pushes the boat along at 200km/h, or about 125mp/h, via a marine jet unit.

Dean regards the Bridge to Bridge as a shakedown cruise for the boat which is intended as Mark's ride in the 2012 world championship jet boat marathon, to be held in the US.

Last year's boat, which Dean also built, was powered by a twin turbo big block Chev.

The fuel consumption of the two engines is similar, says Dean.

The gas turbine consumes about eight litres of JP1 a minute, compared with about seven litres a minute for the V8.

'But it's a lot cheaper to run,” says Dean.

'The gas for the twin turbo costs about $9 a litre – we could burn $30,000 in an afternoon. Instead, this is about $1.75 a litre.”

The turbine runs on jet fuel, kerosene.

With a bit of tweaking, Dean's hoping to get the top speed up to about 217 km/h, or 135mp/h, before the boat is shipped.

At that speed the boat is nearly flying and trim is achieved with canard wings mounted on the bow.

'It's all about getting water into the jet unit,” says Dean.

The boat is on display at Steve's Marine Supplies at Sulphur Point where the engine will be started at 4pm. It's loud.

'I've usually got ear muffs on when I start it,” says Dean.

When Mike Cromie wanted a turbine powered boat for the marathon he went to Art Arfons son in Akron Ohio.

Art Arfons was the land speed record holder in the mid 1960s driving a series of Green Monster jet powered cars.

'It was his son I bought the motors off, and who showed me what we needed to do.”

The engine, on show at Steve's Marine Supplies today at 4pm.

The Bridge to Bridge Water Ski Classic is on this weekend with racing on the Waikato River taking place over both days.

The event has seven components, the main event being the Long Race that is an 82km sprint, against the clock from Cambridge to Taupiri and back to Hamilton.

This race attracts the best ski racers from the North Island and South Island and this year plenty of Australians.

The event starts on Friday night in central Hamilton, on Hood Street, with the Ebbett Prestige Show & Shine.

This runs from 5pm until 7.30pm and is a static display of the powerboats that will be competing in the event.

The first ski race of the weekend is on Saturday morning when the novice, masters and sub juniors race from Hamilton to Taupiri and return.

The next event is the family and social class event, which is a 20km ski on a slalom ski or wakeboard from Ngaruawahia to Hamilton.

It is a race that is long enough to be challenging, but short enough for everyone to give it a go. Any type of boat can be used for this event with a range of classes.

At a glance, the helicopter-modified boat looks quick.

Saturday afternoon is the time trial for the Long Race, which is the crowd's first opportunity to see the main racers in action and gives the competitors a chance to gain top seeding for Sunday's main event. This runs from Hamilton to Ngaruawahia and return.

The last event on Saturday afternoon is the Poker Run, a fun cruise up the river from Ngaruawahia to Hamilton with stops along the way to collect cards which at the end are submitted as a poker hand.

This is not a race as the last boat to the finish line could end up taking the cash prize away.

There are plenty of spot prizes just for turning up and putting the boat in the water and the boat can be almost anything with an engine that floats.

Sunday morning brings the Powerboat Sprints, Thundercats and Jetskis from Hamilton to Ngaruawahia, returning in the afternoon.

The main event starts at 1pm Sunday.

The start in Cambridge will be shown on the big screen at the Grantham Street boat ramp in Hamilton.

The boats will pass through Hamilton at speeds in excess of 160km/h and full noise heading down past Ngaruawahia to Taupiri.

Buckle up!