From: Andy Zeitlin <email@example.com> Organization: The MITRE Corporation Date: 07 Mar 96 02:04:40 References: 1 2 3 Followups: 1
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Currently, FAA and industry are developing a new capability called Automatic Dependent Surveillance - Broadcast (ADS-B) which would broadcast certain parameters in real time, both to nearby aircraft (for collision avoidance, traffic display, or future operational traffic procedures), and potentially to the ground. In the near term, the system probably will use the Mode S data link, which is very limited in its capacity. The messages will carry aircraft position, velocity, direction, identity, but little else. Contrast this to a flight data recorder which tells about engine speeds, flaps, vertical rates, bank, pitch, etc etc. In the longer term, another data link could greatly expand the message contents. However, it doesn't make sense to continuously broadcast info. that rarely will be needed if bandwidth is at all scarce. ATC might make regular use of some data; crashes are rare, even more so where the FDR can't be easily located. Also, the problem of receiving data on the ground implies receivers will be put in place. The problem this thread is discussing mainly applies to a crash far from "civilization"; hence, the low likelihood of finding a receiver there. A better approach might be a satellite-linked path such as ADS-oceanic uses. However, this bandwidth is somewhat limited and expensive. In fact, another satellite, SARSAT, is used internationally for search and rescue; but it couldn't support retrieval of flight data recorder parameters.