Originally Posted by
Torquetalk
The docs referenced above show no ground stations or coverage UK and NI, unsurprisingly. It is the RIM stations that monitor the geostationary satellites (4 now?), and correct, encode and transmit the SBAS signals to the satellites. Each approach has a specific EGNOS channel and reference, so how hard would it be for these to be delisted?
2 RIMS in the UK. They’ve said they will keep them running. The Channel listed against each LPV has nothing to do with any transmission or receipt of a signal. It’s a legacy of how approaches are encoded in FMS. They use the same format as GBAS approaches which were associated with local augmentation transmitters at each airfield. The channel was the output of a mathematical formula based on the VHF frequency used. The aircrew plugged it into their GBAS kit like an ILS frequency. Of course LPV doesn’t have any VHF transmitter but they do need to be unique in the nav database so a big long list of new “channel” numbers were invented. ICAO and the FAA were at various times responsible for allocating these codes to approaches. There is no way of “switching off” channels in the EGNOS system - it’s just a legacy of days gone by.
Also interesting to note all the RIMS in non EU and arguably 3rd world countries who seem perfectly capable of having access to EGNOS from outside the EU….I feel an FOI request coming on here….
