GPS 'drop out'
Yesterday I had a long flight to East Anglia in the morning and my Skymap IIIC worked perfectly.
On the return later in the afternoon I had no GPS fix throughout the whole of the return flight.
I thought perhaps it was my installation but the companion aircraft had no reception on their Garmin handheld either. The only difference was that the return leg was flown 1000' lower then the outbound trip.
Can any of the PPRUNE experts give a view as to what causes this sort of problem. I know that having a properly installed fixed aerial is best but it isn't an option for me at the moment.