"Andrew Gideon" wrote in message
online.com...

For example, how important is a backup electric AI given that we've
standby
vacuum systems (off of manifold pressure)? How does a backup AI compare
to, for example, Cockpit WX, in terms of safety?

Equipment intended for emergency use often has no utility in day-to-day ops,
but may save your hide in a bad space. Think about one of the new 406Mhz
ELTs, for instance. If you never crash where no one sees you, it won't do
you any good. But do the deed out in the sticks and it may mean searchers
find survivors instead of bodies.

I have the precise flight standby system in my 172 and I'm comfortable with
that, but an electric AI is better, so long as you mount it in a reasonable
line of sight. IIRC Mel Carnahan's plane went down with a suspected blown
vacuum pump and a functioning electric AI on the far side of the panel. The
standby vac supports both AI and DG without requiring you to change your
scan, but they have idiosyncracies that an electric AI doesn't.

Personally, I'd be looking at the big 3: weather, traffic, and terrain.
These benefit you every time you fly, VFR or IFR. Flying in the Northeast
I'd sure like to have TIS, and if you do operate IFR a lot, terrain
avoidance gear addresses one of the single most common IFR (and MVFR)
accident modalities. You've already got sferics so you're not blind, but
datalink Wx would fill the picture in much more clearly.

Also, do you have autopilots already? In terms of practical IFR, that's the
first thing I'd add.

Planning? Stockpile a lot of money. That's the only thing you can count on
not changing.

-cwk.