a second. >> yeah. so this one is for mary from tristan. why would one program a computer system if they didn't plan on landing somewhere? >> ordinarily you plan your flight come ut pooers for places you don't intend to land because you have to have emergency plans before you ever take off. you have to have enough fuel to get to your primary and secondary in case something happens. so you actually program and have flight coordinates for airports other than the ones that you're going to but it's to deal with emergencies or weather or problems at the airport and you can't get in. so it's just a backup plan. >> patrick, i want to ask -- let's see. this one is from keith. could the transponder have been reprogrammed to emit a different flight identity? >> no. no. and don, i want to back up a second. richard made a good point a