On Friday, October 11, 2019 at 11:01:09 AM UTC-4, John DeRosa OHM Ω http://aviation.derosaweb.net wrote:
Ever seen one of these? Pictures at; http://derosaweb.net/aviation/cambridge/filter. It seems to have a large ID at one end and a much small ID at the other end.

- What is its function?
- What airline does it go with?
- Which direction should it point?

Back Story: A friend (IA/A&P) was working on the airlines of a glider.
From what I gather there is a Cambridge CVS-50 installed. There is also a
Winter vario installed. He removed all the airlines from instruments
before noticing this hard plastic component until it was too late.
Now he is lost as to what to do with it.

Thanks, John OHM Ω

Oh dear.
Always take pictures prior to removing/disassembling stuff.
I still have a polaroid box camera I used to use for this!
But in these modern times a phone camera is excellent.
Though useless unless one takes the photos, and puts prints
in the box with the parts...
End of sermon, you can genuflect now.

Anyway, you're looking at a calibrated leak for a netto system.
Works in either direction.
But, such things only work correctly at a single weight and
a particular density altitude.
And thus are rarely seen anymore...

See ya, Dave