by MillenniumFlight » Thu Nov 20, 2008 4:54 pm
Don:
Since the terrain isn't going to change much (except for error corrections), I'm not sure I would bother keeping the terrain database updated if I was flying VFR only. In view of new cell-phone towers, windmills etc popping up all over the country, though, I suppose a reasonably up-to-date obstruction database is nice.
However, you don't need all the current instrument approaches, and the airports don't move around, so if you're using the navigator for VFR only work, I don't think I would feel a need to keep those databases current.
For IFR purposes, I understand that the 430/530 navigators must have up-to-date databases to be legal. That's not actually the case for the GX-60 series, which are legal to use under IFR even with an out-of-date database..... all you need to do is confirm the accuracy of the data with current charts, which you have to carry in any case. The reason for the restriction on the 430/530 systems is probably that they are capable of automated frequency switching, which could be a little awkward if a frequency has changed.
For VFR-only work, I would probably update the aviation database once a year, but even that is probably overkill. For my IFR work, the GX60 is my primary navigation source, so I keep that up-to-date. I also keep my 396 database updated, because I use that as a reference for frequencies etc. I update my MX20 MFD annually, because that's really just a back-up, and it's the most expensive to keep updated.
Bryan