The commuter flight that crashed on Alaska sea ice last week, killing all 10 aboard, was part of the workhorse network of short-hop flights that people in the immense and rugged state rely on to get to medical appointments,

Officials are still investigating what caused a small commuter plane to crash out of the sky over Alaska last week, killing all 10 people aboard — but Joel Natwick, a longtime pilot in the state, thinks ice could be to blame.