Roald Amundsen and Umberto Nobile were very different personalities, but both great dreamers.
The former was a Norwegian explorer, an adventurer who had already traveled to both poles; the latter was an Italian aviator and aeronautical engineer who had designed the first airship destined to reach North Pole.
Their collaboration gave life to the Norge expedition, an Italian made aircraft led by the Norwegian chief: in 1926 they successfully flew from Europe to America, being the first ones to fly across the polar ice cap and the whole Arctic Ocean.
Captain Nobile got most of the credit, and inspired by the successful venture he started planning his own flight to the North Pole on a newly-built airship, that he called Italia.
The expedition took place in 1928, but was troubled since the beginning. On the way back from the North Pole, the dirigible crashed onto the Arctic sea ice. Out of 16 crew members, two died during the accident, and six remained trapped in the airship envelope, which floated away and disappeared forever.
The causes of the accident are still partially unknown, but likely fatigue-related: General Nobile was sleep-deprived on that May 25th, and the expedition lacked a second-in-command that could replace him in the lead.
The explorere Roald Amundsen himself died during the rescue mission in the Arctic, while seeking for the missing members of Italia aircraft.