"Most current GNSS use the GPS constellation. However, with commercial use of GLONASS being promoted by Russia and with Galileo sloooowly emerging, will any existing Garmin Wonderbox navigation systems be capable of using systems other than GPS?
I note that EGNOS is supposedly able to improve the accuracy of my automotive Garmin using signals from Inmarsat (ID33) and Artemis (ID 37). However, in practice I've noticed no difference and the system rarely sees any EGNOS signal. Presumably aviation systems track EGNOS in Europe these days?"
Nick,
I'm not convinced that this constant sneering at Garmin GPS navigation systems really does a man in your position much credit. However, in case you had forgotten, the commonest certified GNS fitted to GA aircraft, the Garmin 430 is perfectly able to operate as a VOR in VLOC mode, so the suggestion that they can't operate in any other mode using data from another source is simply not true. As for using the Russian system, I suspect that if there were any suggestion of our systems relying on a Russian satalite network, the CAA would attempt outlaw any kind of GPS navigation, which isn't far from the position we have at the moment.