Another mid-air (UK)
On Thursday, August 7, 2014 8:49:07 AM UTC-7, Stats Watcher wrote:
At 15:04 07 August 2014, jfitch wrote:
Isn't the Flarm GPS WAAS corrected? The WAAS standard of
performance is
1.6M nominal horizontal (95%). When the NDGPS system is
functional (and GPS
engines take advantage of it) this will be reduced to 15 cm.
Not in Europe as WAAS is US only. A search of the Powerflarm
website returned 0 (zero) occurrences of the term 'WAAS'. So it
seems unlikley.... Same result for NDGPS, so that seems unlikely
too.. If someone finds something different I will obviously be wrong
but until that point it's still +-16m (ie a whole wingspan) at 99%
confidence
From the Flarm.com product page:
"FLARM incorporates a high-precision WAAS 16-channel GPS receiver and an integrated low-power radio transceiver. Static obstacles are included in FLARM's database."
Nevertheless, WAAS is intended to correct for atmospheric and geometric anomalies, to improve absolute position accuracy. For gliders in close proximity, these errors are tracking. The fact is, the Flarm GPS has several times the accuracy required to perform the expected function.
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