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Interview with Ann Tedford - 11/8/00

  • Mentioned free-flight as a possible consequence from terrestrial-based to space-based navigation system. She says that it's still far away, and that the current focus is incorporating a solution that addresses a problem. That problem, she thinks, is still not well-defined, because there are so many diverse interests at play. For instance, US ATC systems envision the need to see out to a 60-90 mile radius, but European ATC systems insist they need a 100-120 mile vision. Airlines already have TCAS onboard, and are in controlled-flight all the time. Thus, they don't think there is much to gain from ADSB, at least in terms of safety. However, they do see that they could increase efficiency by using GPS, and thus view the GPS-squitter technology as a traffic-based technology. The General Aviation commitee, on the other hand, has always lobbied for safety, and view ADSB as a way to increase situational awareness and weather reporting capabilities (in other words, they don't care about efficiency). In the end, developing the standards will be all about "balancing budget, technology, and need."

  • FAA's power has diminished in the last 20 years. In the past (before the explosion in the number of airlines, etc), the FAA took a more pioneering and leadership role; they did a lot of coordinating on the equipment buying by many of the aviation players. Today, the FAA "is not in the mandate business." They no longer mandate equippage, so the recommendation is only the first step in standardization. They must now also persuade everyone to follow the standards.

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  • The Story of Mode S: An Air Traffic Control Data Link Technology last modified: 12.06.2000