I'm guessing the previous owner intended them to be water traps; if
the nose statics weren't used they wouldn't bother, and in the TE tube
(although just as likely to give water ingress as the tail boom statics)
might be worried about adding undesirable vario lag.

At 10:55 14 April 2016, Surge wrote:
I'm re-plumbing and re-wiring a Nimbus 2 cockpit and want to know
why there
are filters in some of the instrument tubing.
There is a filter on the nose mounted pitot tube as well as on the
static
tube from the tail boom.
There was no filter/gust filter on the TE tube, nor on the four nose
mounted static ports.

Since I'm upgrading all the flow based instruments to pressure
transducer
based instruments is there any benefit in retaining these filters?
They look like the one on the right in this pictu
http://www.svsponline.co.uk/user/pro...t%20filter.jpg