This is the second in a series.

During the summer of 1925, the United States possessed two giant airships. The USS Shenandoah was designed to be a weapon of war, while the USS Los Angeles was to be a trailblazer for promoting the commercial possibilities of lighter-than-air travel.

There was one major problem: The nation had only enough helium, the nonflammable lifting gas, to keep one of the giants aloft at a time.