Russia's navy said on Wednesday it had launched a new attempt to rescue 116 sailors trapped in a powerless nuclear submarine grounded on the bed of the Barents Sea since the weekend. Two previous attempts to dock a rescue capsule, capable of evacuating up to 20 people at a time, with the Kursk submarine had failed amid fears that the crew was running out of oxygen, Reuters reported Itar-Tass news agency quoted the navy press office as saying the operation started at 8 a.m. A spokesman said the last time rescue vessels in the area monitored SOS signals tapped by the submarine crew was on Tuesday afternoon. The vessels monitor tapping using electronic equipment. Navy commander Admiral Vladimir Kuroyedov said on Tuesday that if attempts to dock with the submarine fail, the whole vessel could be lifted using pontoons. Officials say the Kursk's oxygen supply could last until Friday. Meanwhile, a giant Antonov AN-124 freighter carrying a British deep-sea rescue submarine was reportedly scheduled to leave as soon as possible for Trondheim in Norway, a HeavyLift Cargo Airlines executive said. "We've been given the goahead by the Ministry of Defense and the crew are getting ready," he told Reuters on Wednesday. The 120 ton capacity cargo plane will carry the 21 ton LR5 submarine and support equipment on a two and half hour flight to the Norwegian port. There it will be loaded on a chartered ship ready to help in the rescue of 116 sailors on the stricken Russian Kursk submarine. He said he did not know whether the Russian authorities had made a formal request for assistance. The aircraft is operated by HeavyLift and its Russian joint venture partner, Volga-Dnepr Airlines.