Billionaire Microsoft founder Paul Allen and his mega-yacht Octopus were in the middle of an expedition last night to recover the sunken bell on the HMS Hood. The mogul set off with the British Royal Navy letting them use his 414-foot yacht free of charge, to raise the massive brass bell from the cruiser sunk in 1941 by the German battleship Bismarck in the freezing Denmark Strait between Greenland and Iceland. Allen is onboard Octopus and live-tweeted how they launched the ROV submersible to the wreck more than 2,800 meters below, before they had to reposition it because of strong currents. He wrote, “Recovering ROV to fix issues . . . another dive in a few hours hopefully, we did verify we are on the right spots and saw pieces of HMS Hood.” Octopus Capt. Glenn Dalby said: “The weather and associated sea conditions are as challenging as we expected . . . however the subsea current has been far greater than we anticipated. Our confidence remains high that we will have a successful recovery despite these hindrances.” HMS Hood, on which 1,415 perished, was the largest British ship ever lost in battle. The bell will be displayed at the National Museum of the Royal Navy in Portsmouth, England, in 2014.