Joshua's RV-9A Project

Finished pulling the phone and mic lines through the airframe, and soldered them to the corresponding jacks.  Terminated the transponder and #2 comm antenna coax and installed the antennas, at least temporarily (they’ll eventually have a bead of sealer underneath).  I may end up putting doublers in for the comm antennas, as the skin flexes a fair bit with left/right motion of the antenna.

The audio system essentially complete, I had an urge to test if the jacks were wired correctly.  Slid the audio panel and intercom into their trays, hooked up the two test leads from the VP kit to the master buss feed (one at a time, first) and flipped the switch…lit right up, beautiful.  Once I had both running together (I knew there must be a reason VP provides two test leads!), I fetched my headset and plugged in.  Works like a charm; audio is there, the PTT’s on the stick and the canopy deck work.  I had to look up how to adjust the sidetone volume on the SL-40, as it comes set quite loud.  Tested the copilot side too, also works.  I think I have an old headset knocking around in some random box, I’ll have to pull it out and test it so we can both plug in at once…better than standing around talking to myself on the intercom!  I couldn’t remember the AWOS freq for any of the local airports, though I doubt it would have come in anyway (nearest field is ~15 miles away).  No music input handy to check that with, so that’ll come later this weekend.  No noise heard from the panel or cabin lights, either.

Finished up the wiring of the GPS/Icarus distribution block, crimped sockets on the ADS-B wires, and checked through the wirelist for the 430.  Everything had been run except the ground wires, which were somehow left out, so I ran those in place.  That essentially finishes up all the behind-the-panel avionics wiring, so I went through neatening and putting final wire ties on everything.  I still need to terminate the cables to the 430, and run the mic/phone lines aft.  Started feeding those through the fuselage, and got as far as the spar before bed called.

Once those last few wires are in, all that’s left to do electrically is plug in all the boxes and fire it up.  Wiring has taken more time that I expected, and it doesn’t look as perfect as I’d hoped, but I enjoy the process and the work, and it’s a bit sad to see the end; though I’m excited to get the AFS screen and light that up.  I expect that something will have gone awry and will need troubleshooting, too.  Next, it’ll be on to the engine sensors and control cables, which means I should get the exhaust on order (and sort out what prop I’m going to use, so that can be ordered if it has a long lead time!)…but with the avionics purchased, I’m back to waiting for the money tree to bloom before any of that can happen.

Many tie wraps were harmed in the making of this project…

Decided to go ahead and provision the mounting points for the ADS-B box above the VP CU.  I offset the mounting points to the left side, so the units are not centered on one another, to give a better mounting geometry.  Two of the bolts for the ADS-B will also penetrate the VP mounting bracket, which will clamp it down even more; those two will need to be removed to remove the VP CU, but the other two will hold the ADS-B box in place while it’s out.  Seemed like a reasonable compromise deal, so it’s done.  Of course, done in this case just means that the holes are drilled & deburred, and a template made for future use.  The nutplates will be installed on the mounting brackets of the box, with hex head screws capturing it from below.  I have tried to install everything forward of the subpanel with a mind toward working on it laying under there on my back…no fasteners that need to be access from the top, nothing should needs in-situ soldering to remove, and so forth.

That figured out, I went on wiring the feeds to and from the box; serial to the AFS screen, encoded altitude, antennas, and a serial service port.  I’ll need to order another minijack for the service port connection.  Ran the power and ground wires, which were the last of the power system wiring, so I started tying up those cable paths.

Spent some time working on a distribution “manifold” for GPS signals from the 430, which need to go several places, and the encoded altitude signals (aka Icarus) from the AFS, which also go several places.  Wired up a 15-pin D-sub with a series of jumpers to give 4 points for GPS and 3 points for Icarus, and began wiring it in.

…and still more left to do.

• Pulled in the ARINC lines between the EFIS, autopilot, AP source switch, and 430.
• Wired the autopilot controller connector.
• Drilled a hole, installed a rubber grommet, then wired and installed a mating connector for the GPS 18x.  I wanted a connector on the subpanel to allow the canopy to be removed (since the current plan is to mount the GPS on the glareshield), and the connector is also a convenient spot to split the GPS signal out to multiple devices: the EFIS, ELT, and APRS all receive a feed, and another line will run to the 430 location, to feed the devices that will take their GPS signal from the 430 (autopilot, transponder), until the 430 is installed.  I put female standoff nuts on the connector, so the connector on the GPS end can be fixed to the subpanel connector.  The connector mounts in a rubber bushing to allow it to be pulled out for service when needed, to add or remove a device.
• Re-ran the boost pump annunciator wire using a route that made me happier.
• Decided to locate the ARINC module on the outboard side of the left subpanel rib; this is pretty open from below for access when it comes time to install the module, and I will drill the mounting holes now, install nutplates,  and make a template to keep on hand for later, when the box is in hand and brackets need fabrication.
• Ran the wires to the ARINC module location and terminated the module connector.
• Tidied and tied up some wire bundles, most notably everything in the switch row.

Need to figure out if the SL-40 should be receiving any serial feeds; can the AFS push frequencies from it’s database?  I don’t have any open serial ports on screen 1, but I have a spare on screen 2, which would allow me to use that feature (assuming it exists) once I have the second screen.  Also need to figure out where the ADS-B box will reside and sort the wiring to that.  Wondering if I might install rails to mount it above the VP CU, though that’s a lousy spot for accessibility, and worse for installation/removal (at least without pulling the CU first).

Started the day by removing the panel after marking where the top of the subpanel cutout needed to be.  Filed the opening up to the line, and fabricated an angle to reinforce the left side of the cutout.  Panel back in, and marked the angle to drill a mounting hole for the SL-40 tray.  Primed and painted the angle and riveted it in place, and put in all the panel mounting screws.  It’s pretty solid, even without any attachment from panel to subpanel (except via the radio stack).

With the panel in, it’s time to get to work wiring.  The rest of the day was spent working on wiring the panel, both to itself and to the airframe.  There’s not really much to show, since it doesn’t look much different than it did yesterday.

• Drilled out the pitot heat indicator holes for LED holders and inserted some LEDs.  I was originally going to just Goop the LED’s in place, but this allows for the possibility of serviceability, at a minor aesthetic expense.
• All the wiring to the VP CU is complete, except for the backup alternator, since I don’t have that, nor do I know where it will be mounted.  The only “flying lead” at this point is for the ARINC converter, as I don’t know yet where that will mount, either.
• The power and grounds are run for the radio stack, and some other connections have been made, such as transponder encoder input and audio from EFIS 1.
• All antenna cables except for the ADS-B and GPS 2 (which is to feed the ADS-B)  have their panel ends terminated.
• All the switches are hooked up, as are the annunciator lights.
• The CO/SpO2 sensor’s serial connection is done.
• DB backshells are on the CO detector and both of the VP CU connectors.
• The PTT switches on the canopy decks are connected.
• Airframe autopilot wiring is routed, and a terminal block installed for the power and ground–a single power line feeds both servos plus the control head, so it needed to be split.
• A million zipties, give or take a few, have been installed and cut away.
• Scratched the panel on the upright between the EFIS screens while being (apparently) careless with a screwdriver.  Dang.  Will have to figure out how to best repaint that segment.

Need to look up a few things, and hopefully will get in a couple hours tomorrow between church commitments.

The only picture I managed to take today…

Some more progress on the panel tonight, things are shaping up nicely.

Installed the LED strips that will provide the backlight for the switch legends.  There being no easy way to make a mechanical attachment (riveted Z-clips would work, but that would require more holes through the panel, and I already painted it…), and the LED’s having an extremely long expected lifespan, I clamped the channels to the back of the panel and affixed them with several spots of Goop.  After setting, it should provide a solid hold, and still be easily removed if needed for service or replacement of the light strips.

While the glue was drying, I marked and cut the hole in the subpanel that provides room for the radio trays and harnesses to pass through.  The right side is quite stiff, as it’s immediately adjacent to the subpanel rib, while the left side is a bit floppy.  I’ll run a piece of angle vertically along the left side to reinforce it there, which will also provide a convenient place to tie the radio stack to the subpanel if that appears beneficial.  I had to provide a larger cutout above and below the trays that actually penetrate the subpanel (430 & SL-40) — even though the others (audio panel & transponder) are not that long, the bundles of wire exiting their connectors are too close to bend to a central hole.  I had previously installed a rubber grommet for that purpose, which is the reason for the half-circle cutout at the top of the stack.

Once the clamps for the backlights were removed from the panel, it was time to fit the radio trays.  This was a relatively simple task, since the stack angles were already drilled for the trays and riveted in place.  It’s a little tricky to work with nuts & washers in the small space between the left side of the stack and the adjacent EFIS tray, but persistence and appropriate tools pay off.  I had picked up a long #1 phillips screwdriver earlier in the day, which came in handy for the skinnier trays; the transponder is a bit taller than the others and a stubby driver will fit inside.  I used a square to set the trays perpendicular with the panel face and tightened them down.  A test fit of the SL-40 and transponder said that alignment of the faces was still good, and the audio panel tray was adjusted until the gap between it and the SL-40 was equal front-to-back.  Once everything was in place, I made some straps to tie the rearward portion of the trays together.

At that point, I had to see if the trays would align with the subpanel cutout, so the whole assembly was set in place on the plane.  The cutout was almost perfect, though I need to trim a little more off the top of the large center portion, to ensure that the 430 tray will fit through there when the time comes, without the need to go in and file it out later.  The left stiffening angle also needs to be installed.  Allison came out to inspect the progress, so I hooked up the light switches and dimmers and we messed around with the lights for a bit.  The backlit switch labels turned out exactly as I’d hoped, they look great in the dark.

The panel, having sat for a couple days to let the paint cure, was ready to have some parts loaded.  The paint turned out alright, though there are a couple blemishes I’m not too worried about them.  Took some time tonight to attach the placards, then loaded in the switches, dimmer pots, and annunciator lights, and tightened the nuts down.  To finish it off, I loaded in the CO/SpO2 detector, and the blank panels for the autopilot and 2 1/4″ instrument hole.  The blanks for the second EFIS and the 430 still need to be fabricated, and the radio trays installed, though I need to cut the subpanel hole as well.

Panel looks pretty good!

Started off working on the panel, by riveting the EFIS trays in place.  The design of the trays really helps stiffen up the panel, pretty much eliminating flex in the vertical, and the radio stack angles help as well.  Once the EFIS trays were riveted in, the panel was clamped to the bench and I started fitting the radio stack trays.  This was fairly easy, using a ruler, calipers, some wood blocks, duct tape, and a stack of popsicle sticks for fine adjustment.  Once the trays were clamped in position, the mounting holes were marked with a drill bit, center-punched, and drilled to size on the drill press.  Dug around for suitable screws to mount everything, and the SL-40 needs thin washers on either side, as it’s tray is just a bit narrower than the rest.  I aligned the 327 and SL-40 to the bottom of the panel cutout, and the audio panel to the top, and the resultant gap in the middle measured out at the right size for the 430…the miracle of CAD.  Finally, took it all apart to debur, prime, and rivet together.

Once the panel was all riveted, I scrubbed the rivet rows with scotchbrite and slathered on a light coat of epoxy.  When it cures, I’ll sand it smooth, which should effectively make the rivet rows disappear when painted.  I wouldn’t have bothered with this, but there are a couple of extra holes that needed to be filled, because of the late discovery that the right rib would need to be moved.  Found that the epoxy takes awhile to cure, 10-15 hours according to the can (West Systems w/206 hardener).  Should be ready for sanding & paint tomorrow if I bring it inside overnight.

With the panel curing and unavailable for further work, I set upon other tasks…torqued the CHT sensors and put drip loops in their leads; this lead to fabricating and installing the starter cable, more adel clamps installed to hold that cable and give a place to tie the CHT’s to.  EGT’s will tie into the same place, but with no exhaust system, it’s hard to install those!  I’ve left the cable unattached at the starter end, to avoid inadvertant activation.

Finished installing the nutplates for the manifold pressure sensor, and bolted that in place.  Connected the silicone tubing from the sensor manifold to the sensor.  Filed down the center heat box cable eyeball to give it better grip on the cable, the finished installing that cable and terminated on the flapper arm.

Started on installing the wiring for the AFS system, by running the magnetometer wires to the tailcone.  I hope I’ve got everything I need back there, because there is zero room left in the snap bushings at the rear spar bulkhead…  The only thing that is left to go aft of the main spar (except for all the connectors, of course) is the mic & phone lines, which won’t need to pass through the rear spar bulkhead, than goodness.  The magnetometer wires were just long enough to get where they need to go.

Those lines in, worked on the rest of the AFS wiring, putting in the engine monitor harness, after removing a bunch of pins from the connector, inputs such as amps, trim, and flap position, which will be supplied via the VP-X system.  Figured out which wire was which, and ran them to the approximate locations FWF.  Removed the pre-installed fuel level wires and replaced them with the ones already run in the airframe.  Switched the RPM input line to the electronic ignition pin, to connect with the Pmag.  Sensor harness done.  Next up, the main harnesses, running serial and audio wires in the right general directions, power & ground, and tying up the external inputs, as I don’t believe I have any uses for them at the moment.  I may just pull these from the connectors as well, and stash them aside with the wires I pulled from the EM harness, for later reinstallation when necessary.  Along with all this wiring, of course, goes the regular installation of bushings, grommets, tie bases, and so on, as and where necessary.

Discovered that the adel clamps I put in to secure the wire bundle on it’s vertical run from the tunnel to behind the panel, -14′s — which I assumed were oversized and would be swapped with something smaller once wiring was done — have reached their capacity.  I have 4 more wires to insert there (mic/phone lines), so they’ll probably need to be -15′s.  Of course, the next larger size I have from -14 is -18.  Sigh.

To do:

• Print alternator wiring diagram
• Print mockups of ARINC and ADS-B boxes for panel space arrangement
• Find torque spec for oil temp sensor
• Install starter cable boots, torque starter cable at contactor
• Run additional ground wires for EFIS case grounds (18AWG)

Lots of parts new to the shop at the moment — recieved an order of adel clamps and misc. hardware from ACS, random stuff from McMaster, a crimper frim Digikey, and picked up a boxful of Garmin gear, plus a box of engine sensors, from SteinAir yesterday.  The AFS screen isn’t ready yet, hopefully in a month; word is that there’s a shortage of a part needed to build them.  I did get the tray, sensors, and all the harnesses, so there’s plenty to be done, and the screen should be able to pop right in when it’s ready.

Tonight I sorted a bunch of hardware into the bin racks for easy access later on; washers, nuts, nutplates, and so forth.  Also sorted the large collection of adel clamps I’ve amassed; pretty much fills a medium sized cardboard box.  (In case you’re wondering: the engine mount tubes are -12 and -14; you’ll want lots of those.)

With the adel clamps neatly organized, it was a good a time as any to start clamping things.  Worked on securing the alternator wiring and other wires that run around the engine mount.  There’ll be plenty more clamping to do as more wires get added to the FWF.  Put rubber grommets in the subpanel wiring harness holes, and ran the CHT/EGT harness through to start looking at wire run paths.

Worked on the panel and trays: modified the right edge of the EFIS 1 tray where it interlocks with the other one, drilled and countersunk the rivet holes to attach it to the panel.  Stripped part of the primer off the panel where I’ll use epoxy to smooth over the rivets around the trays and radio stack.  Primed the tray and back of the panel.

Pulled open the box of engine sensors and distributed them around: put the CHT’s in the cylinders finger-tight, the oil temp in its place.  Started work on mounting the manifold pressure sensor by drilling for nutplates, but called it a night when it was ready to rivet, since it was past midnight (think of the neighbors…)

More wiring work tonight, doing some bundle tying and terminations.

• Tied up the bundles forward of the subpanel, so that things would be at the correct place for cutting to length and termination.
• Crimped the Dsub pins and installed into the connectors on the Vertical Power CU.
• Shrunk the labels onto all the wires currently running to the CU.
• Combed out bundles and rearranged some support brackets for better runs and to avoid chafing.  Also added some split brake tubing over a couple nearby edges, in case vibration moves the bundles closer over time.
• Rerouted the master buss feed to travel through a rib using a snap bushing, rather than under it with an adel clamp; this gives me better separation between that big wire and the bundle of other wires that has to pass under it.
• Changed the power feed to the light dimmer to use the spare slot on the terminal block I mounted to the lid, to use as a buss point for all the interior lights.  (The dimmer module is fed from here, which drives 4 channels of lighting; a line runs to the map light panel overhead, and a third line will provide power to the annunciator lights).
• Combed out the mess of ground wires at the firewall, crimped on connectors, shrunk the labels, and landed them on the ground block.  Added a ziptie base to secure them on the route up to the block.

Got word today that my avionics are ready to be picked up, once I get them some money.  Hopefully by the end of the week, since I don’t have much going on next weekend…it’d be exciting to have the panel fired up by this time next week.  It’s also time to measure for control cables and fuel lines, and order that stuff up, since it’s all made-to-order pieces which may take some time.