Originally Posted by
BuzzBox
I think there are two major reasons. First, there simply isn't enough bandwidth available using 'traditional' systems such as VHF datalink and SATCOM. CVRs and FDRs generate a huge volume of data and when you multiply that by the large number of aircraft that might be airborne in the same area at the same time, the available bandwidth isn't sufficient to reliably support data streaming. Second, is cost. Data streaming is expensive and nobody's been able to justify the extra cost on safety grounds. That said, technology is constantly changing and there will no doubt come a time when streaming of CVR and FDR becomes feasible. Mind you, international regulatory change normally take years so it will no doubt be a long time before data streaming becomes the 'norm'.
I'm not an expert on satellite communications but would be interested to hear from anyone that is. Do the SATCOM packages installed on civilian aircraft require the antenna to be aligned with an appropriate satellite? If so, it is likely that any uplink is going to be terminated at the point where you are going to most want the data from the FDR/CVR when the aircraft departs from controlled flight (assuming there is such a departure).