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Old October 31st 11, 12:08 AM posted to sci.geo.satellite-nav,rec.aviation.ifr
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Posts: 6
Default PRN133 ranging now useable for SoL, at non precision approach level

On Oct 30, 4:44*pm, macpacheco wrote:

NASA JPL operates a Global Differential GPS system with worldwide
coverage. They claim 10cm performance.

'The NASA Global Differential GPS (GDGPS) System is a complete, highly
accurate, and extremely robust real-time GPS monitoring and
augmentation system'.

I believe the John Deere Starfire commercial service is based upon the
NASA system.

Why can't airplanes use it ?

--- CHAS