acars system that sends back data about the plane's health were apparently switched off. >> it wouldn't surprise me at all in the aftermath of this investigation, a safety recommendation comes typically from the national transportation safety board, certainly this country, to say you just have to put on a tracking system in every airliner that cannot be disabled. >> reporter: another piece of technology that could be due for an upgrade? flight data recorders. their batteries are only require too old last 30 days and, what's more, the signals they send have a range of only about two miles, making them difficult to find unless search teams are close by and lucky. athee that jones, cnn, washington. we'll update you on the latest of the search for the flight coming next and look at what the u.s. is contributing to the search coming next as well. we'll also take a look at other international headlines. ukrainian men join the military as fear of russian forces grows. [ garner ] there's a lot of beautiful makeup out there,