The flight over the Transantarctic Mountains took about an hour. Sunlight glistened off the exposed expanses of blue ice on the glaciers. Although the roar of the Herc engines precluded much talking in the hold, in the cockpit Margaret and Brian had radio headsets on so they could discuss the landing spots with the pilots. As we circled around the area we could see that the route we had chosen up the McCleary Glacier was going to be a challenge for there were several large crevasse fields along the way. We would have to stick closely to our planned route, which looked safe enough visually, but one could really never be sure until you were there on the ground.
Crevasses have a bad habit of being lightly snowed over.
This occurs when winds blow fresh snow across the crevasse and it freezes to form a bridge of thin ice. Later, after light snow falls blanket the whole region, the crevasse becomes virtually invisible. It then turned around and came in to land. Landing on the ice is always a little dangerous as no one can exactly predict or know what the conditions will be like. If a large crevasse had been covered over by snow, the plane could suddenly crash down into it and the plane would cartwheel over on the hard ice.