Ships and aircrafts have been at the site where the UC3 Nautilus submarine sank on Friday August 11, off the Danish coast, to try to salvage the vessel.<br /><br />Entrepreneur Peter Madsen, from Denmark, made headlines when he successfully financed the building of the submarine through crowdfunding.<br /><br />He designed and built the UC3 Nautilus along with fellow submarine enthusiasts in 2008.<br /><br />After being rescued, Madsen was arrested on suspicion of murder after a Swedish journalist who joined him for the voyage was reported missing.<br /><br />Madsen, 46, denies killing the missing woman and says he dropped her off on Refshaleøen island about three and a half hours into their trip on Thursday night.<br /><br />The only people on board were Madsen and the journalist, whose partner alerted authorities to her absence on Thursday evening.<br /><br />The police in Sweden said they had tried without success to contact the woman by phone. Her family had not heard from her.<br /><br />Madsen, an entrepreneur known as an artist, submarine builder and aerospace engineer, is appearing before a judge for preliminary questioning.<br /><br />Police said the submarine was on the seabed in Koge Bay, south of Copenhagen, at a depth of seven metres. Divers had not been able to enter the vessel.<br /><br />Madsen said “a minor problem with a ballast tank … turned into a major issue” that caused the sinking of the vessel.<br /><br />The ballast tank is a compartment that holds water to provide stability for a vessel.<br /><br />The 18-metre Nautilus is one of three subs built by Madsen. It can carry eight people and is considered to be the largest privately built submarine of its kind.<br />
