On Feb 23, 5:52*pm, Papa3 wrote:
On Feb 23, 1:08*pm, "Bill Daniels" bildan@comcast-dot-net wrote:



Simularly, fusing pressure data with GPS altitude data could work the same
way. *For example, a millisecond scale spike in GPS altitude, not confirmed
by presure data could be ignored with impunity. *A slow drift of the
pressure signal from the smoothed GPS signal is almost certainly a synoptic
pressure change and can be canceled by the long term stability of the GPS
signal making the pressure signal more useful in detecting airspace
incursions. *(Think automatic Kollsman settings.)

Bill Daniels

Which, interestingly, is exactly what the $200 Garmins with Pressure
Sensor do!

P3

So, in effect, IGC/GFAC are holding back progress on better altitude
measurement--at lower cost--by refusing to allow [certain] COTS
receivers? Come on, folks, this is the 21st century. Technology
should be welcomed, not feared!

Chip Bearden
ASW 24 "JB"
USA