Anything that might make the plastic tube "bunch up" so as to create a leak
path is a bad idea. Wire and clamps seem to do this. The solution is
"castrating rings" (No kidding).
See: http://www.agri-pro.com/Castrate.html#rings

Roll one of these over the plastic tube after you slip it over the aluminum
tube to get an air tight fit.

Bill Daniels

"Ernest Christley" wrote in message
.. .
What is the best way to secure plastic tubing to aluminum pitot tubes.
The plastic hose will slide over the aluminum tube, though it requires
quite a bit of push to get more than 1/2". Would a couple of spring
clamps work, or is something more significant called for?