i m david muir. on world news this sunday, what happened? new clues tonight in the deadly air crash over the hudson river. and the view from the cockpit tonight from pilots forced to fly in busy skies. the power struggle after a cia missile strike kills a taliban leader. infighting over who should lead the taliban next turns deadly. the u.s. capitalizes on the chaos. the manson murders 40 years later. crimes that horrified the nation. why is there now a fight to free some of those murderers? and the daily snooze, the surprising number of americans sneaking a nap while on the job. and why some say their bosses ought to be thanking them. captions paid for by abc, inc. good evening. they have been pulling wreckage and bodies from the hudson river here in new york all day today after that midair crash yesterday between a sightseeing helicopter and a small plane. all nine people aboard the two aircraft were killed. tonight, investigators are learning more about how this ha