The Aspro provided anything but pain relief when it sank to the bottom of Wollongong Harbour on Thursday night.Visitors to Belmore Basin yesterday watched on as an 80-tonne crane and a team of divers worked to retrieve the vessel.The Aspro's owner Ron Baxter was at a loss to understand how the 9m timber boat sank.The 88-year-old said he had checked on it just three hours before it was found underwater at 8pm."I saw it at five o'clock, another guy saw it at six o'clock with no water in it. There was nothing wrong with it," he said.Despite the boat being 60 years old, he said it was in shipshape condition having just passed a surveyor's inspection for insurance purposes."It's only just been done up to make it brand new again," he said.The boat was previously employed as part of Mr Baxter's Illawarra Communications service, assisting vessels with radio problems.Long since retired from official duty along with its owner, it is now used for fishing trips. It is not the first time the boat has sunk. Its first trip to the bottom occurred about four years ago, when the pumps failed during a heavy storm."But this time around the pumps were new," Mr Baxter said.Gwynneville man Bud Stjepanovic, who berths a boat near the Aspro, said vandals could have been responsible for the sinking. He said boats in the harbour were often attacked by intruders, with thousands of dollars' damage resulting over the years.Mr Baxter, a Wollongong great-grandfather of eight, said the cost of yesterday's retrieval, which took about four hours, would be about $15,000. Despite the two sinkings, he has no intention of retiring the boat."Why would I do that? It's a beautiful boat - and it's younger than I am!"