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In
the February issue of PMY, editor-in-chief Richard Thiel cautioned
readers to always navigate with a pencil-on-chart backup plan because
GPS–in fact any electronic device–is inherently susceptible
to failure. Frankly, I was a wee bit skeptical. While I’ve regularly
heard old salts like the chief expressing wary views of high-tech ways
around the bridge, I’ve personally experienced a high degree of GPS
reliability, not to mention the splendid operating features of GPS-driven
chartplotters and PC nav programs.
Nonetheless, with more
references to "GPS vulnerability" cropping up in the press,
I decided to do some deeper research. I’ve now actually read the
113-page Vulnerability Assessment of the Transportation Infrastructure
Relying on the Global Positioning System, also known as the Volpe Report,
after the government research center that compiled its dry text. In addition,
I spoke at length with a gentleman named Langhorne Bond, who retired from
public service in the transportation sector–including a stint as
Administrator of the FAA–only to spend the last five years shouting
from lonely rooftops about the dangers of over-dependence on GPS. I surfaced
with an entirely new attitude. It appears that the satellites seduced
a great many of us, from top government regulators on down; and it’s
time to get real.
When the U.S. military
released a GPS frequency for civilian use in 1990, no one anticipated
how rapidly it would turn into a widespread technological religion. Soon
I was packing my adored handheld on yacht deliveries and, like many of
my brethren, thought the evolution to constant plotting on digital charts
was the greatest advancement in navigation since radar. In 1994 the Coast
Guard announced that Loran, the previous somewhat cranky method of electronic
navigation, would be phased out in 2001. Foreign stations were turned
over to host countries, and the market for Loran pretty much vanished.
Aviation authorities
also began to see GPS as a total electronic navigation solution. Both
the Coast Guard and FAA started working on their own "differential"
systems to overcome the Selective Availability (SA) inaccuracy mandated
on civilian GPS to prevent enemies from using it for targeting. In fact,
about this time last year, the big GPS issue for us marine electronics
pundits was the relative merits of the FAA’s WAAS versus the Coast
Guard’s DGPS. How naive we were. Both have value for intensely precise
navigation, but the truth is that when SA was rather suddenly turned off
in 2000, GPS became sufficiently accurate for most pleasure boaters.
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Dark Side continued > Page 1, 2,
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