instrument pitot/static thread sealer or dry?

[scard]

Is any kind of thread sealer or other compound called for on the (plastic) NTP threads of the pitot/static connections on instruments? I'm thinking these should just be dry but would like confirmation.

[Ironflight]

I've always installed them dry Scott, but I can't cite any documentation that says that. Never had any leaks I coudln't solve with a little more tightening...

Paul

[robertahegy]

The plastic fittings (the pipe thread part) should be dry and only slightly more than hand tight. I think the tube and nut end may bottom out on most types. Any thoughts on that out there?

Roberta