[Buy the Way]

I bought-a flying RV-9A that I've equipped for IFR. It has the baseline bent-tube pitot installation, which I'd like to replace with a heated pitot. (I've read the back and forth about the need for this change, just want to cut to the chase here assuming it'll be changed.)


Apparently others have done this swap by expanding the hole at the existing mounting location, but I'm put off by the difficulty of accessing that spot through the rib separating it from the outer access panel. Mounting to the outer panel itself isn't attractive due to interference with the tiedown and possibly the bellcrank, as others have noted, but how about using the middle panel, which I didn't find discussed?


I imagine one concern would be interference by flow from the prop tip. The pitot input would be about 5' behind the prop and about 6.2' from centerline, while the prop radius is 3', so it doesn't seem like an obvious call either way. Does anyone have practical experience as to whether this could work, or perhaps know of a study that might be applicable?

 

[Mike S]

Mike, welcome aboard the good ship VAF

 

[blaplante]

You might want to think about adding AOA capability while you are at it.

I'm trying to visualize the spot, I think I have it in my mind correctly. The job seems far from the most awkward thing I've had to do. Wouldn't you make all the enlargement cuts from outside (bottom of wing) up into the wing? Then just a matter of fasteners and attaching the tubing. Pre mounting a quick fitting such as https://www.steinair.com/product/fitting-straight-18-npt/ on the pitot mast will make the line fitting easy.

 

[mburch]

The toughest part of this job will be running the wires - the actual installation of the new pitot mast and associated pitot plumbing tweaks will actually be fairly trivial in airplane-building terms. Mark your new hole location in the wing skin near the bellcrank, get out the tools, and make a hole! If the edge of the hole isn't quite perfect, a proseal bead will cover it.

 

[ERJDriver]

I did a dynon heated pitot on a flying 8, put it in the next rib box outboard of the inspection panel and mounted the controller to the inspection panel plate. 0 metal work experience, had a guy that built a 7 help. Was easy

 

[rockyfatcat]

I'm doing the IFR upgrade. My aircraft used to have the simple bent tube. My avionics guy recommended the Garmin AOA/ heated pitot and gave me the part number for the installation kit. It mounts the AOA/heated pitot tube to one of the removable inspection panels.