Prandtl multi probe receptacle used for TE only?

On Wednesday, February 14, 2018 at 3:44:59 PM UTC-8, Dave Nadler wrote:
Hi Matt!

On Wednesday, February 14, 2018 at 6:03:47 PM UTC-5, Matt Herron Jr. wrote:
I have a Prandtl type receptacle in the fin of my ASW27.
The previous owner converted to to TE probe only, by tying off the static
and pitot lines behind the panel. Anything wrong with this set-up?
I get my static from the ports on the boom about 2/3 back.

You mean a 3-way probe, right?
The probe pitot and static are better than fuselage ports (though pitot
is easily wiped out by a bug). If your instrumentation is working OK with
fuselage ports, why mess with it?

I guess there would be more potential for leaks, at a minimum.

Nope.

will the extra volume of air connected in the unused tubes create
any adverse effects on the TE line?

No, they are not connected in any way.


See ya, Dave

The three circuits are not supposed to be connected, but if there is a bad O-ring, all bets are off.
In a perfect world, your system as plumbed will work fine. If the mod was done due to crosstalk, and there is a leak in the plugged static or pitot lines, it will be erratic.
After the lines were disconnected and plugged, there's a chance nobody has leak checked them.
They're a pain to replace. I have a spare fitting for ASW27/28/29 at home, hope to never need it. Fortunately my leak was found to be two things, a bad probe and a hidden connector in the back of the panel, which Rex found instead of replacing the fitting.
Jim