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 minute ago, it's real important that we establish the timeline, the communications timeline versus the acars timeline, make sure they match up and make sure that's accurate information before we start to rule out certain possibilities. meanwhile, mr. beatty made a comment a minute ago that i almost had to jump in.