11.   The round-the-world balloon trip is described as the last unconquered aviation challenge.

12.   Three balloonists streaking across the Pacific Ocean were caught in a dangerous weather system early Friday that threatened their attempt at the first nonstop balloon trip around the world.

13.   Three balloonists streaking across the Pacific Ocean were caught into a dangerous weather system early Friday that threatened their attempt at the first nonstop balloon trip around the world.