LOCKHART, Texas — It appears a hot air balloon made contact with high-tension power lines before crashing into a pasture in Central Texas, killing all 16 on board, according to federal authorities who are investigating the worst such disaster in U.S. history. A power line was tripped at 7:42 a.m. Saturday, and the first call to 911 came a minute later, National Transportation Safety Board member Robert Sumwalt said during a news conference.