I was reading some NTSB reports (i.e. plane accident reports), and read about yet another instance when a plane had been vectored into a mountain, or a plane heading right for a mountain in VFR but with quite poor visibility, never got a call from the air controller who got collision alerts on his radar, because the controller felt the pilot didn't need the help because he was flying VFR (that turned out to be incorrect, but his call cost several lifes).
Anyway, I came to the conclusion that since I had decided that I was going to get my instrument rating (IFR), I would not want to rely on just a few old instruments in the plane, and a controller who after all is human, and could make a fatal mistake one day. It did not seem to make sense to fly without visibility, at night, or in instrument conditions, without a GPS with terrain awareness (i.e. a map showing you terrain around you that is close to your altitude, or above you)
Given that, since I was going to get some new piece of handheld equipment, I decided to go all out and just get the best available today: A Garmin 496 with XM weather. I ordered it overnight on thursday and got it on friday in time for my saturday flight to Reno.
I've then spent most of my Sunday reading the manual and playing with it.
My impressions are:
- It's really a full IFR GPS except that because Garmin can't get it certified, it says everywhere "not for use for IFR", but it seems much better than most IFR certified GPSes out there
- It has high resolution terrain awareness, just what I wanted
- XM weather is quite nice. Ok, it's a $50/month XM satellite radio/weather subscription, but I think that's well worth it if it can help you avoid a mountain wave, or "controlled flight into terrain" (that you couldn't otherwise see)
- Real Time TFR information is even better. Nowadays, TFRs can pop up anywhere, even while you are in flight, and you are somehow responsible for avoiding all of them. Graphical TFR zones that show up on my moveable map screen just seem essential. Now, if you're sold on that, try up to date AIRMETs, and SIGMETs. That too, is essential in my opinion.
- XM radio is a nice added touch. I didn't have XM radio at home, and now I do :)
- It's also a very good car GPS, and even a marine GPS with sonar capability.
- My first down point on it is that you can't use its internal memory to upload new maps. You have to buy some custom Garmin memory that is huge in size and price. They really should have used an existing format like CF or SD/MMC
- My other problem with it is that the connectivity it's supposed to have with other Garmin equipment that's already in planes, is effectively useless: you need an aviation shop to do custom wiring work beforehand, which means that as a renter, you can't hope to use TIS (which would have been useful), or exchange data with other avionics inside the plane (A Garmin guy told me that the FAA prevents them from uploading a route or flightplan to an IFR GPS anyway, because their equipment isn't IFR certified, so it can't upload data to IFR equipment. Swell...)
In a nutshell, while it's not cheap, neither is renting a glass cockpit equipped aircraft, and flying with a Garmin 496 comes close, but you can do it in an older plane with antiquated avionics that you can then proceed to mostly ignore.
Unfortunately, the GPS doesn't have RAIM, but still has very good accuracy through tracking up to 12 satellites. I guess you just have to be careful to have a track on enough satellites + WAAS to know that you are getting reliable position data
Two essential features for me were real time TFR info, as well as terrain awareness when you can't see what's around you
Winds are both essential to know which altitude you'll get the best winds at, but also when you're thinking about crossing a mountain ridge
If you lose your instruments, a GPS derived backup might still come in handy
It's not a Garmin 1000 (for one it won't talk to your autopilot), but it gets close