Kristin Paniptchuk’s water broke on Christmas Eve at her home in the western Alaska Inupiat village of Shaktoolik, and then she began to bleed profusely. Five days after a military helicopter and then a cargo plane whisked Paniptchuk to an Anchorage hospital, she delivered her daughter Kinley, premature but healthy. The Alaska Air National Guard conducted 159 such missions last year in largely roadless Alaska, many during vicious storms.