Pictures of Angle of attack install in 7A
Hi Bill, sorry for the delayed response. We had a couple epic winter flying days, and I just adopted an un-started RV4 project.
Here is a photo of the installed ADAHRS in the rear fuselage:
I have back up steam gauges on the panel in addition to the rear mounted ADAHRS unit, so I teed the static line in the rear fuselage and ran a line forward, and also teed the pitot line under the pilot seat and ran a line forward and aft.
Here is a photo of the A of A line running aft to the rear fuselage:
I drilled holes for grommets in the side fuselage bulkhead ribs for these lines because the quick build floor came riveted from the factory. I will run these under the floor if I have the chance to do it again
Here are the tubes and wires mounted through the wing ribs
I would have preferred to run the wires in a lightening hole further aft. The adhesive is a tough commercial sealant to stop chafing the pitot or A of A lines
I find it interesting to be writing on this this topic now, because I was uncertain how to handle it a couple years ago when I was completing the wings and fuselage, and paid close attention to what others were doing. Now that my airframe has 100 trouble free hours on it and I am planning my next build, I would offer the following suggestions:
Plan all your systems before you close any structure, and run all the required wires in advance. I got too focused on completing the primary structure, and paid for it later by performing wiring yoga in the completed airframe. In addition to pitot tube plumbing and wiring in the wing, consider antennae, nav light, stobes, syncronizing wire, landing light, wig wag, fuel gauge, auto pilot servos, and the associated grounds. In addition to the ADAHRS in the rear fuselage, consider ELT, Transponder, nav/com, ADS-B, position light, OAT, trim, and other remote equipment. Even if you don't install equipment now, run the wires if you think you may want it later.
I have practiced landing in day VFR with instrumentation covered up, and will not bother with back up steam gauges in my next build.
I much prefer AN rubber grommets to Van's plastic grommets for running electrical wire. The plastic grommets work fine for pitot static plumbing.
Look for opportunities to run multiple devices on shielded multi conductor wire to save weight, money, and clutter.
Jay