A father and son have been rescued after their boat crashed onto Black Jack Rocks at the mouth of Hobart's River Derwent on its maiden voyage.
The pair from Western Australia were suffering from hypothermia after their six-metre pleasure craft, worth about $100,000, became stranded on the rocky reef south of Hobart.
Police say the pair, aged 73 and 48, struck the rocks near South Arm just before 7:00pm Thursday night on their initial trip from Orford.
Inspector Lee Renshaw said it took water police about an hour to actually locate the boat on the reef.
"One of my staff then got off the police vessel onto the reef, managed to get both parties off the boat onto the reef," he said.
"One of them went into the water, Constable Fogarty managed to grab him before he disappeared into the drink, and then we got them onto the police vessel."
Inspector Renshaw said it was a difficult rescue in the dark.
"Obviously, the water's very cold, but there was a bit of swell about last night which made it difficult for the police vessel to get them off the reef, it took a bit of time but we managed to get them," he said.
"It's an unforgiving environment ... you've got to plan your trips a bit better, in any event it's happened and it's unfortunate and the best thing is they are both still alive."
Black Jack Reef is synonymous in many Tasmanians' minds with the grounding of an InCat ferry during sea trials in 1994.
It took salvage crews eight weeks to refloat the ferry.
