Fuselage Wiring

January 23, 2022 Georgeairplane, avgeek, aviation, Dynon, engine, Flying, Fuselage, homebuilt, pilot, RV-7, vansaircraft, Vertical PowerLeave a comment

Today I did a lot of wire organizing in the forward section of the fuselage, under the panel. All of the cables routed from the aft fuselage and under the seats funnels into the center section and routes on the floor up to the panel.

Once I organized the rats nest of wires I ended up with two nice bundles. These include the two trim motors, flap motor, ADSB, transponder, ELT, and ADHARS unit. These will be wired to the different serial and power connectors under the panel.

On the right side of the fuse I’ve separated out the radio antenna wire so that I reduce interference as much as possible. This will be behind there side panel from my interior, so it won’t be seen. The RG400 coax wire has a minimum bend radius of 1in, which I am well above in all these bends.

On the left side of the fuse I’ve bundled my two autopilot harnesses. These are separated out from the power wires and autopilot disconnect which will route directly to the pilots stick. The Dynon autopilot harnesses are the standard SkyView Net 9 conductor harnesses except for power. So the only wires needed are the paired data wires.

Here are the Dsub15 connectors for the GPS, ADSB, and Transponder. The red wire for the ADSB and Transponder are left off the connector in order to connect to the VPX. The GPS is powered by the SkyView screens, so it’s fully pinned into the connector.

There are 5 components that use serial connections. In order to connect all the serial to both the PFD and MFD screens, I made a serial bus board that has 7 connections. These are all hooked up in parallel on each pin. When I connect all the connections to the board, each screen will be hooked up to each component properly. I’ve done the pins so that each Rx and Tx from the screens are assigned properly.

VPX Installation

January 16, 2022January 16, 2022 Georgeairplane, avgeek, aviation, Dynon, homebuilt, pilot, RV-7, vansaircraft, Vertical PowerLeave a comment

Yesterday I spent most of the day at the hangar cleaning up and working on the installation of the VPX mounting brackets.

I started with the rough position of the mounting brackets under the sub panel ribs. This will be the final position of the VPX under the panel.

Each corner needed a nut plate installed, so I match drilled the brackets to the ribs, and then lined up the nuplates and clamped them in place.

I then drilled all the nut plates, deburred, dimpled, and riveted the nut plates to the sub panel ribs.

Here’s the close up of one of the nut plates riveted in place with the angle bracket loosely held in place with a mounting screw.

During the day, a friend of mine visited the hangar to check out the project. He took this awesome picture, thanks for hanging out (and helping) Andrew!

It was fun to chat about the project, and airplanes in general. I always enjoy sharing my love for aviation with other people.

Later in the day, I received a nice shipment from Dynon! My autopilot panel, and my comm radio were delivered! These are some of the final components in my avionics package. The remaining component is the second HDX screen.

These buttons are very satisfying to push! I’m looking forward to installing this in the plane soon!

VPX Wiring

January 8, 2022January 8, 2022 GeorgeLeave a comment

Today I spent a few hours working on the main power harnesses. Since I’m using the Vertical Power VPX, all the power wires connect to a central distribution point including the panel switches. It’s all very straightforward once you have the pins all planned out.

Here’s the VPX mounted under the panel (it’s all upside down) so that I could reference the two D25 connectors for J1 and J2. The J8 connector, as well as the J10 and J12 connectit’s on the other side are used for the larger power distribution, whereas the J1 and J2 connectors are for switches (connects to ground), flap position sensor, and serial Tx/Rx for communicating with the EFIS.

Here’s the backside of the J12 connector. Not all the pins are used, and they are left empty. I used my heat shrink tubing labeler to mark each wire for each of the five connectors.

Here are all five of the main power harnesses completed. The final wire runs will need to be done in the plane, but that won’t take too much effort once I rivet in the sub-panel and can start installing components. There are 50 wires here that each are labeled with their respective pins and connectors in order to easily route and attach to the correct components. I genuinely enjoyed this work and look forward to more of the avionics installation and wiring!

EMS wiring

November 7, 2021November 7, 2021 Georgeairplane, avgeek, aviation, Firewall Forward, homebuilt, io-360, pilot, RV-7, vansaircraft, Vertical PowerLeave a comment

This weekend I spent time working on the main EMS wiring harness. It includes everything for engine monitoring including oil pressure, temperature, fuel flow, fuel pressure, manifold pressure, rpm, etc. It’s quiet extensive.

I started by reviewing my wiring diagram that I made, and reviewed the pin out of the EMS D37 connector.

I then opened up the main harness that is included in the skyview EMS in order to identify every pin.

I used my multimeter to check each wire and then I used that to label each one according to the function.

Here’s the EMS and the main harness (silver) plugged in. As you can see in this picture, the wires are labeled and then separated out into the appropriate pairings (e.g. oil pressure power, ground and signal). Then I began to wire the engine sensors and measure the wiring runs.

Here you can see the main EMS harness come through for all the firewall forward components. Mounted to the top of the firewall is the sensor manifold, which includes oil pressure, fuel pressure, and manifold pressure.

Here’s the oil and fuel pressure sensors mounted to the firewall. These are wired into the main harness and share their 5v source on the same pin (pin18) of the EMS. It’s a common source for low power components and is shared between several other sensors.

Here’s a close up of the oil temp sensor wired to the harness.

Here’s the manifold pressure sensor. It has a tube that’s connected to a T in order to share a manifold pressure source with the ignition system. E-Mag ignitions also need to know the pressure of the intake in order to adjust timing of the spark.

Continuing the work is a bit slow, but it’s getting there. Lots left to do.

Roll Trim System

June 23, 2021 Georgeailerons, airplane, avgeek, aviation, homebuilt, pilot, RV-7, vansaircraft, WingsLeave a comment

This weekend I spent a few hours working on the roll trim system. I’m using the Ray Allen trim system from Vans, so everything is nicely packaged together into its own subsystem.

I started out by modifying the plastic block that holds the pivot arm. This needed two holes drilled through it foe the AN3 bolts that hold it to the aluminum plate. I also botched the larger counter bored hole to allow access to the cotter pin that holds the pivot arm in place.

I then trimmed and match drilled the mounting plate to the seat pan holes. This allowed for a perfect fit. Once I drilled the two holes on the left, I temporarily installed it to drill the two holes on the right to the floor ribs.

Here you can see the original hole where the nut plate was. I removed the nut plate and then used the center hole to mount the plate in order to drill the bottom hole. This was done on both sides of the center channel.

Cutting the pivot arm to the right length

I then cut the pivot arm tube to the right length so it can sit in the block and then be mounted to the metal plate. I cut off about an inch of tube. Once I did that I drilled a 1/16th hole for the cotter pin.

After drilling the block to the mounting plate, I dimpled, and mounted the nut plates to the mounting plate. I will complete this plate by priming it before final installation.

I then installed the pivot arm into the plastic block, and then installed the washer and cotter pin to hold it all together.

I then test fit the assembly by installing the bottom two screws. The top two are where the floor is held on to the ribs. The pivot arm needed to be adjusted to not rub on the control rod.

In the bottom left is the servo block. I need to drill that to the floor rib for final installation as well.

The final thing to do next time is to finishing the assembly with the control stick springs and cleaning up the assembly with some final adjustments.

Wing tank brackets

February 8, 2021February 8, 2021 GeorgeLeave a comment

This weekend I spent a few hours working on the plane. I wanted to get some specific things done in order to make a little progress towards fitting the wings.

I spent the day installing the fuel tank attach bracket to the outside of the fuselage. This required fabricating the internal support bracket and spacers. It took a little longer than I though, but got it done.

After taking these pictures, I buffer and then primed the brackets. These are steel so they are very susceptible to corrosion. Now that these are installed. I can prep to mount and test fit the wings!

After this I spent an hour or so finishing up the exhaust hangar modification. I didn’t take any pictures, but because I’m using the Vetterman 4 pipe exhaust and the heat muff, the standard Vans exhaust hanger can’t be used on that side. So I fabricated a support bar that shifts the hangar mounting point outboard of the heat muff. I finished it by drilling the bolt hole for the mount and attaching it with all metal lock nuts.

I also removed the bolts for the exhaust attaching it to the engine in preparation for riveting the firewall to the bottom skin where the exhaust exits the cowl. This isn’t accessible when the exhaust it attached to the engine.

Fuselage gussets

December 30, 2020 Georgeairplane, avgeek, aviation, engine, Flying, Fuselage, homebuilt, io-360, pilot, RV-7, vansaircraftLeave a comment

Today I spent a couple hours putting the forward fuselage gussets in place. They are unique to the -7 vs the -7A. The tri-gear plane rear landing gear are mounted just forward of the center section. Since the -7 is a tail trager, there is a gap here that need to be reinforced using these gussets. They are attached to the sides of the fuselage with 5 bolts that need to be match drilled. The gussets also line up with the bottom wing attach bolts.

I lined everything up and then drilled the holes to #40 and then enlarged for the AN3 bolts. I prepped and primed these and then attached them to the fuselage. The whole interior will be painted with my interior paint, but it’s good to prime all the parts especially mating surfaces.

I also sent a bit of time working on the panel attachment brackets. Since I’m using twin Skyview HDC screens, I need to move the Vans panel supports inboard. This requires making some custom brackets to attach the panel to the sub panel. I received a shipment of L stock from vans that worked perfectly for this.

I decided to wrap up the center section bolts that are used for the tricycle gear. In the tail dragged version the bolts need to be put into the center section.

The bottom bolts were difficult to reach but everything is now in place and torqued.

I also placed the remaining two cover supports on the sides of the fuselage, forward of the center section.

Next up is to wrap up the exhaust hangar modification. And to drill the wing fuel attachment bracket to the sides of the fuselage.

Behind the scenes and Wire Harness

December 21, 2020 George2 Comments

Over the last two weeks I’ve spent many hours working out how much stuff there is left to do. I put together a list of everything I can think of, adding effort estimates to each item and adding time spent.

Google sheets has been awesome to organize my to-do list. I’ve completed about 100 hours since I made the list a few months back, so I’ve updated it all to be as accurate as possible. I then took the remaining items and I’ve been organizing them in a JIRA project I made to track my active work. This is a product I use at work on a daily basis to manage my teams’ projects, so I figured I’d try it for managing my own project.

Here is the collapsed view of my project. By using this interface I can manage all my project links on the left, as well as drag and drop my to-do items into their respective statuses based on what I’m working on.

An Item I just completed – the full aircraft wiring harness. I’ve spent the last week designing and verifying the wire harness using http://www.diagrams.net by Google. Its been great to look at pinout diagrams from my avionics suppliers and then visualize the harness pin-to-pin. It really helps me to understand the way I will make the harness.

I made a system overview block diagram to make sure I was accounting for all the items in the system. This probably doesn’t have every item, but it was still great for visualizing the system.

I then used all the documentation I had for all the ECUs and components, and made the full system wiring harness. Again, I think this has everything covered, but I will continuously be checking the system before completely turning it on. I have a power supply that I will use for testing that has protection circuits in place in order to prevent any overcurrent or shortage issues.

Closed out the wings!

November 22, 2020November 22, 2020 George3 Comments

Today I hit a huge milestone! With the help of my fiancée Britney and my friend Mina, we were able to close out the final skin on the wings.

With all that’s going on, I was worried that I wouldn’t make much progress on the project, which has turned out to be somewhat true. But when I do get to a new milestone, it feels amazing.

After we wrapped up the final rivets, Mina helped me put the wings back in the cradle. I couldn’t help but take a wide angle pic of the whole hangar. There is a lot more space now that the wing isn’t on the saw horses.

There’s still lots to do on the project, but getting to this point has been a great adventure!

Vertical Power PPS

July 21, 2020 Georgeairplane, avgeek, aviation, Firewall Forward, Flying, homebuilt, pilot, RV-7, Vertical Power1 Comment

This weekend I had a few hours to work on the plane. It’s been a couple months since I’ve spent a good chunk of time on it.

I decided to take off the old conventional master and starter contractors. I’ve decided to go with Vertical Power Primary Power System. This is a single unit that replaces the contractors, as well as current shunt and fuses. I’m also using the Vertical Power Pro solid state VPX. These two will work really well together.

For easiest access I mounted this on the edge of the firewall near the battery as far away from the exhaust as possible. Every bolt and post is accessible. I also crimped on the ring terminals for the alternator and for the starter once I had this mounted.

I also wired up the J1 harness that includes all the inputs for the master switch, battery and alternator current sense and fault indicators. This will all feed into my EFIS and be displayed on the engine monitoring page.

RV-7 N890GF

Build Log for George's RV-7 Project

Menu

Author: George