>> and the disappearance highlights the weaknesses in aviation tracking technology. andrew stevens is joining us live now from hong kong. it's been a year since 370 disappeared. tell us about the changes in technology now to make sure that a boeing 777 doesn't just disappear off the radar again. >> well it's still a very much work in progress at this stage, zain. when mh 370 disappeared, the transponders were sending back at an interval of every 30 minutes information about the location of the plane and its general well-being as far as the aerodynamics and the engines were concerned. so that would go back every 30 minutes. now the transponders were then turned off. so nothing went back. so what the global authorities civil aviation authorities are now work on is to get that 30-minute interval to cut back to 15 minutes. so every 15 minutes, there would be a signal sent from the