If my refreshed G memory serves, it was a four sided glass tube "loop"
with vertical instrument panel mounted portion indicating pitch via fluid
level while firewall vertical portion was much shorter and remaining
portions were therefore not parallel. Apparently it was used on early mail
planes after WW1 for flight in IFR conditions. Believe thinking at the time
,how simple to replace "glass" with plastic tubing..

Thanks for the comment but in any case, it is the airspeed alternative I'm
seeking.


"Paul Tomblin" wrote in message
...
In a previous article, "Dick" said:
A while ago, I remember someone describing an attitude gage consisting of
a
tube loop (the loop was orientated fore and aft) filled with a liquid.

That wouldn't work. It would point straight down during an coordinated
turn.


--
Paul Tomblin http://blog.xcski.com/
We'll burn that bridge when we come to it.