I spent a long time trying to decide if using smaller diameter tube runs would be detrimental to the air speed and AOA readings, when building the wing I did not want to drill any extra holes if I didnt need to. So after much research I could not find any reason why using 4mm tube (about3mm ID) wouldnt work. After connecting everything up today I made a test rig to blow a fixed velocity of air at the pitot head, I got a reading of 58 mph on the Dynon and a similar reading on the standby ASI. Just to put my mind at rest I then swapped the tube for the standard 1/4 and got exactly the same readings.
Connected the Pitot head to the tube runs
The big advantage of the smaller tube, they will pass through std grommets
And I have run them alongside the wiring and up the coduit to the rear of the panel
