last-known position but almost nothing else to go on. >> reporter: so far, no one has heard the underwater pinger attached to the black boxes that should be good for up to 30 days. no emergency locater beacon signals and no radar track showing where the plane might be. >> meanwhile, nbc's keir simmons is in malaysia with more on the search and, frankly, the families that are frantic. >> hey, chuck, good morning. ware hearing from reuters quoting a malaysian military source who says it believes it may have tracked flight 370 all the way west of here to the straits. at the same time the plane itself stopped giving out signals hundreds of miles northeast of here over the south china sea. that suggests that it may well have diverted and traveled some distance before it did finally disappear. >> that would go to the theory of going back to that payne