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Old June 22nd 11, 01:15 AM posted to rec.aviation.soaring
Eric Greenwell[_4_]
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Default Midair in Finnish nationals

On 6/21/2011 1:56 PM, Mike Schumann wrote:


The reality is that FLARM, ADS-B, or any other GPS based technology is
useless in collision avoidance at close quarters. At the very best, the
position accuracy is only 50 ft and is only updated once a second.
Flying at 50 knots, you are traveling ~70 ft / second, so a lot can
happen between updates.

These systems are great in warning you about aircraft in your area that
you might otherwise not be aware of, and to give you an overview of how
many aircraft are in a particular gaggle and their relative altitudes,
but you absolutely can't rely on them for collision avoidance in a thermal.


Is this conclusion based, at least in part, on your personal use of
FLARM in several contests?

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm
http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what
you need to know tinyurl.com/yfs7tnz