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.