Dynon GPS Doubler

The Dynon GPS will go on the top skin behind the baggage compartment.  I didn't have enough aluminum sheet stock to make doublers for all of the antennas, so I ordered a bunch of .063" sheet from onlinemetals.com.  Given that they have a location in Seattle, it ended up being a great way to go.  I'll have to remember that for the future.  I cut out a doubler just a little bigger than the GPS puck and drilled holes for the rivets to the skin and for the nutplates for the GPS screws.  I had to put a slight bend into the doubler to match the skin.

The other GPS (Garmin) will go a little further aft and to the other side of center.  For whatever reason, the installation instructions for GPS antennas say not to put them on the center line, hence the reason they're offset.  The second antenna also needs to be at least 12" away center-to-center.

ADAHRS & Flap Position Sensor

Catching up on a couple of days of work, although it's work that is 90% thought and 10% result.  The ADAHRS is mounted on the J channel and rib behind the baggage bulkhead.  I don't want to rivet it in place until after the top skin is on since having it in place would make it difficult to buck the skin rivets.  I want as much as possible ready to rivet once the skin is on though.  The pitot, static and AOA tubes insert into the ADAHRS from the front side and the dsub for the wiring on the aft side.  I don't love that the tubes would just be supported by the ports on the ADAHRS though, so I decided to make a bracket to rivet forward of the ADAHRS to pass the tubes through.  I knew there was a reason I keep all of my castoff parts!  I cut a chunk out of my junked rear wing spar and repurposed it for the bracket.  I'm just going to call the pre-existing holes from the wing spar lightening holes.  I just saved a few hundredths of an ounce!

One of the many other tiny tasks I have to complete is getting the flap position sensor set up.  I played around with it for hours trying to get the connection to the flap arm correct, but never quite got it right (the big movement of the flap arm has to translate into only 1" of movement of the position sensor).  I ordered some longer threaded push rod, so once I get that I'll take another stab and it.

Subpanel - ADSB & Transponder

The subpanel work continues.  I came close to making a mistake in placement of the ADSB and transponder.  I looked at a diagram from AFS that showed some suggested mounting locations on a RV7 (same as RV9).  It had the ADSB and transponder up near the top of the right side of the subpanel.  It seemed fine, so I started to lay things out.  That's when I realized that their diagram was for a slider canopy, not a tipup.  When the tipup canopy is closed, the front of its frame takes up almost 2" of space at the top of the subpanel.  Thankfully I realized that before I drilled any holes.  I moved the boxes down to clear the the frame and mounted all of the nutplates for them.

Once I buy the Dynon radio, that box will probably go right next to the ADSB (that's the black one).  Hopefully that gives enough space for the center radio stack, which is going to require a big hole to be cut into the subpanel to allow for the depth of the eventual IFR GPS.  Not being able to slide things up towards the top of the subpanel really limits the available real estate.  Things are going to be a lot tighter than I thought.  If push comes to shove and I don't have enough room on the subpanel itself, I will create some brackets to mount additional boxes between the panel and subpanel.

In preparation for routing the wires from the firewall to the subpanel, I riveted a cross brace in between the two outer ribs.  This will give me more flexibility in where I can put wire bundles.

The last thing I did today was route the static tubing from the tailcone up to the panel.  The AFS screens don't need the static input at the panel (the ADAHRS for the screens will set behind the baggage bulkhead and the static/pitot/AOA lines go there), but any backup EFIS that I use will require a static line to be the most accurate.  The Garmin G5, which I'll probably use as my backup, can operate without the static info, but having it allows it to be more accurate by not just relying on GPS data.  The tubing runs just under the longeron, so aside from being seen in the baggage area, it should be completely hidden.

ELT & ACM

A long time ago I installed the ELT mounting bracket from Van's.  It was a real pain to install because of how it's riveted to the J channels.  So I was thrilled to discover today that the mounting holes provided by Van's don't match the holes required by the ELT I bought (a little odd, given that this is also the ELT that Van's sells).  There wasn't really an easy way to drill new holes and install nutplates with the bracket in place, so I had to drill out all of the existing rivets and pull the bracket out. With it out, I drilled new mounting holes for the ELT and put nutplates in place.  Getting the bracket back on the plane was easier said than done, just like the first time!  It looks so simple, but the bottom pop rivets are inside, between the bracket and the side skin.  Of course as is par for the course in airplane construction, it took ten times longer than I thought it would.  With the nutplates in place and bracket installed, I mounted the ELT plate and strapped the ELT on.

After struggling with the ELT I needed something simple to do, so I pulled wire to the subpanel for the Dynon GPS puck that will go on the top of the tailcone just behind the baggage area.  The wiring is turning into spaghetti and needs to be organized, which means it's time to actually start mounting things to the subpanel so I can figure out routing.  I located the ACM as low as it could go on the subpanel and installed nutplates for mounting.  Things are starting to look real!

Roll Servo & OAT Wiring

Not much to report today, aside from tidying up some wiring.  I routed the roll servo wiring up to the corrugated tubing and pulled it through.

On the left wing, I finally made use of the hole in the spar flange that is supposed to be used for Van's homemade pitot tube.  Since I went with a pitot tube that looks like it belongs in this century, I had the hole to either fill or use.  Luckily it's the right size for the outside air temperature probe.  I put the probe in place (loosely - it'll have to be pulled away a bit to paint) and pulled the wires through.  I haven't been able to figure out a super clean way to punch through the tubing, so my method of choice is simply a rough cut hole and RTV to hold things in place.  It's kind of odd - the instructions for the OAT wiring say that if you need to make the wire longer or shorter, cut it in the middle and splice more wire in.  The wires come pre-crimped to some tiny molex connectors that connect to the ADAHRS module, so I'm assuming the instructions are there because most people don't have crimpers that tiny to deal with putting new pins on.  The wire is barely long enough to reach the fuselage, so I'll definitely have to extend it.

Autopilot Servos

The Dynon autopilot servos have arrived!  Pitch and roll use the same model of servo, just with a slightly different attach point on the servo arm.

First step for the roll servo was to wire a 9 pin dsub connector onto it.  I must have forgotten how to count when I placed my original wiring order, because I am missing a number of dsub clamshells.  Given that a lot of builders don't even use clamshells and just leave the dsub connectors bare (every ounce counts I suppose), I am not going to stall out waiting to order more.  I have all I need to still be able to connect the dsubs with screws, so the shell is just window dressing.  That being said, since these servos get hidden out of the way, I decided to zip tie the connectors together as well as use the screws.  Belt and suspenders approach.

Installing the roll servo in the right wing wasn't hard, just fiddly.  It was very doable with the wing already closed up, but definitely would have been easier had I done it when everything was still wide open.  I had to do a lot of head scratching on the install - the drawings on the installation instructions don't show how a number of spacers are put in place to offset the pushrod.  Well, they do attempt to show it, but the angle of the exploded view they chose to include in the instructions covers up so many parts that it's impossible to see how it all goes together.  Someone was sleeping on the job when they decided that was the view to use.  After a lot of research, including finding an old version of the installation instructions online that had a useful drawing, I finally got everything sorted out and installed.  My first attempt at safety wire (on the three bolts that hold the servo to the bracket) was super ugly.  The second attempt was passable.  For such a simple task, I still don't have the hang of it.  I suppose learning to do it in a small confined space wasn't exactly setting me up for quick success.

I still need to figure out the wire routing up to the corrugated tubing.  The pushrod will also need to be adjusted once the wings and ailerons are mounted.  I couldn't figure out a good way to adjust the length of the servo pushrod without having the aileron in place to identify the neutral position.

I wired up the pitch servo the same way - my last remaining clamshell and zip ties.  Working on the pitch servo was far easier just because of the open access to the area.  Once again, safety wire was my downfall.  One of these days I'll figure out the trick to it.