Two researchers and their pilot were rescued from an Alaska volcano Friday, according to NBC News. They were stranded after their helicopter's blades were covered in ice by freezing rain. The researchers had been working on recovering short-term volcano-monitoring equipment, according to The Associated Press. When freezing rain iced over the helicopter's blades, the three became stranded. The freezing rainstorm started Wednesday evening, and the bad weather prevented an earlier rescue. A rescue helicopter airlifted the trio to safety Friday, but the iced-over chopper was left behind on Mount Mageik, the AP said.