A Russian tanker carrying desperately-needed fuel supplies for the far northern Alaskan city of Nome keeps getting stuck in thick ice flows as it crosses the frigid Bering Sea in the dead of winter.

Fortunately, the 370-foot tanker Renda is escorted by a specially-designed Coast Guard ice breaker, the USCGC Healy, whose extra-thick hull is capable of crashing through ice several feet thick.

But that means going is slow. The two ships are covering just five to six nautical miles a day, even though they still have more 300 miles of sea ice to burst through before they can reach Nome.