Fisrt of all, Thanks for all of the great information. It helps a bunch.
As for why I need two airspeed indicators, I'm planning to use a standard
airspeed indicator (read cheap) to start with, and I want to eventually
place a Dynon Aviation EFIS-D10 in the panel when I'm finished. I just
wanted to know if I needed to replace my old airspeed indicator or could tee
in the new instrument. Plus I didn't want to have to add a second
pitot/static system if I didn't have to. Thanks again

Louis G.

"Jay" wrote in message
om...
Curious why you would do that in the first place? Couldn't you get
away with GPS speed (average of 2 runs in opposite direction to pull
our windage) to check your differential air pressure based airspeed
instrument.

Also, if you put 2 instruments on the same ports, one of the biggest
sources of error (port placement) will be applied equally to both
instruments.

I'm leaning towards the idea of an all electronic panel (GPS centric)
with minimum no-electric emergency cluster.

Regards

"Louis Gallego" wrote in message
news:kdMKb.80815$xX.581325@attbi_s02...
Does anyone know how one would install two separate airspeed indicators?
I
suspect one would need a separate pitot tube systems. Is this correct?
Also, how does one go about correcting an error (either too fast or
slow) in
the indicator. I'm 2/3 done with the fuselage of my Zenith Zodiac 601XL
and
was just thinking ahead.
Thanks in advance,

Louis G.