If a pressure transducer vario and a flow measuring
(mechanical or electric) vario share the same TE line
and that line is divided near the varios then there
cannot fail to be some degree adverse effect on the
pressure transducer vario as varying the flow up and
down the TE line generated by the flask vario will
cause pressure changes that will be sensed by the pressure
transducer - especially if any sort of restriction
is placed in the TE line on the probe side of the division
of the line to the 2 varios. If you do mix the 2 vario
types then divide the line as far aft along the TE
line from the varios as you can reach.

The flask vario is the only pneumatic instrument in
the panel that measures flow - all the others are various
types of pressure sensor.

John Galloway


At 21:00 24 February 2005, Bruce wrote:
Time to start a new debate.

How do pressure transducer varios compare to traditional
mechanical varios in
club use?
Can you mix and match a capacity vario and a pressure
transducer vario on a
single TE probe?
Do students - please note NOT experienced pilots -
find the lcd display units
easy to use, or are moving needle varios better (I
know we should be using the
audio - but for the times when we want to see the climb
performance the question
is still valid)

We are looking at replacing some vintage mechanical
varios, and have some debate
about the advisability of needing electrical power
for the vario and the
relative benefits of the Borgelt B40 and the Tasman
V1000, and of course another
set of Winter mechanicals...

Being a computer type, I am biased towards the 'no
moving parts' V1000. So - any
views?

Bruce