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Van's standard pitot tube is simply a piece of aluminum tubing which comes straight down from the main wing spar and is bent to point forward. It's effective, simple and cheap, but is not heated. I plan on flying IFR, so I need a heated pitot tube to cover the possibility of getting caught in icing conditions.

I bought a standard AN5812 heated pitot tube from Aircraft Spruce, and a mounting kit from GretzAero. The mounting kit is very well done. The bracket is a piece of aircraft streamline tubing welded to a plate, and the whole thing is nicely chromed. A backing plate to rivet inside the wing and all the needed hardware are included. The instructions are very clear.

The pitot tube was a pretty tight fit into the mount. I had to put a bit of never-seize on it to allow it to slide in without scratching up the chrome on the pitot tube. One of the bolt holes on the mount had to be enlarged slightly with a needle file to allow the mounting screws to fit properly.

I will be using the Van's standard static source on the rear fuselage because it appears to work well, and should not collect ice. I will have an alternate static source in the cockpit just in case. Some builders use an AN5814 pitot tube with static source, but I would expect to get large static source position errors that way. A static source needs to be in an area with the same pressure as the free stream air, but a wing is specifically designed to have high pressure underneath, so it takes a lot of trial and error to find a decent location for a wing mounted static source.


Read on for more.

A piece of angle (supplied by the builder - I used some left over from the elevator stiffeners) is riveted to one of the wing ribs to better tie the backing plate into the structure.


The forward edge (at the top in this view) of the backing plate is joggled so that the forward part overlays the back edge of the main spar. This allows it to catch the rivets at the back of the spar. The joggle was only 0.040 inch as it was originally designed for the RV-4 and RV-6, but the RV-8 main spar is 0.063 inch thick, so I had to make up a spacer plate (0.020) to get the fit that I wanted. That is my only complaint with the mounting kit and it is a very small issue for the builder to deal with.

The four large holes on the backing plate are where the flat head screws go that hold the chromed pitot tube mount in place. The smaller holes are for the rivets that hold the backing plate to the wing skin.

I moved the pitot tube one bay outboard from Van's location to get it further away from the tie down. The location of a pitot tube is not critical as long as it is clear of the prop-wash, out of the boundary layer, not in the wake of anything, and is aligned within about 10-15 degrees of the local airflow.

All in all, I am very satisfied with Warren Gretz's pitot tube mount. pitot tube mount clecoed to wing skeleton.