Wiring / Cleanup

I have been working on cleaning up the wiring mess I created for myself.  I call it 10 lbs of poop in a 2 lb bag.  But realistically, if you add up the weight of all the avionics and wiring its probably closer to 30 lbs all in.  Not that I have weighed it.

Having a super light engine, my plan was to move as much forward as possible to help offset the weight.  Between the panel and the firewall are the following components:

• 2X 10.3" displays
• Backup EFIS
• Prop controller
• Advanced ACM
• UL ECU, boost controller and aux box
• COM radio
• Room for IFR GPS and NAV/COM
• Avionics backup battery
• Header tank
• Audio panel
• EMS
• ADSB receiver
• Hall effect sensor
• GPS 2020 receiver
• Skyview expansion bus
• And all the normal 'stuff'.

Add all that together, and its 10 lbs of poop in a 2 lb bag.

Top down view of the mayhem...

The relatively clean panel hides the mayhem that hides behind it.

The GOOD news is everything works.  All the avionics are connected, the ECU is talking to the EMS, all the controls on the sticks do what they are supposed to.  Radio / audio panel / audio all works.  Servos are talking to the system.  Prop controller has power and just needs connection to the hub.  All of the lights (nav, strobes, taxi, landing, panel, overhead) all work.  Pitot heat is ready to go once the wings are attached and wiring finished.  ECU indicator lights.  Circuits for the engine and transfer pumps.  It all works.  Yay me.

It's not 'pretty' like I hoped it would be.  But to move the weight forward and contain it all between the panel and firewall is an extreme challenge.  If I could get rid of the ACM and use CANbus only, it would be way neater - but that is not the path I chose.

Once the weather dries out a bit, the engine will come off and the real firewall will go in, and then I can finish up the firewall forward wiring (fuel pumps, batteries, relays, shunt sense wires, prop controller, etc)

I am tired of wiring, and look forward to building parts again (which is totally ironic).

Merry Christmas.

Update...

Progress is being made... albeit slowly.

The wiring on the 'Longnose' Sportsman is pretty much done.  The last bits remaining:

1. Wire fuel pumps from the switch to the pumps.
2. Alternate air switch / panel indicator
3. EarthX battery fault wires
4. UL regulator to main bus

And thats pretty much it.  Everything else is installed, wired an functions as expected.

I have the next 1.5 weeks on vacation, and have a few goals to accomplish:

1. Clean up the rats nest of wiring.  OK, its not THAT bad, but needs some TLC
2. Finish the last of the firewall penetrations and determine routing for the prop controller to prop cable, EGT's/CHT's, cabin heat cable, fuel injection return, boost controller lines, and thats about it (as if that's not enough LOL).
3. Pull the engine and put it back in the crate
4. Drill the 'real' firewall
5. Rivet the flanges on the real firewall
6. Adhere the firewall blanket
7. Install the firewall and rivet it in place.
8. Rehang all the firewall components (regulator, coils, fuel pumps, relays, batteries, etc)
9. Reinstall the engine

Is all that doable?  Maybe - we will see.  I think I can get 1 through 7 done before January 2nd, maybe more.  But you have to have goals, right?

IF I can get all of the above done, then its onto engine / firewall forward 'stuff':

1. Oil cooler mount and lines
2. Oil cooler opening in the front of the cowl
3. Intercooler mounting
4. Ducting for the intercooler
5. Air intake and filter mounting / plumbing
6. Alternate air inlet
7. Finish the exit air ramp on bottom of cowl
8. Cowl 'finishing'
9. Cowl fasteners
10. Windows (front, top deck, doors (x3), fuselage) - the front window will be last (and probably just temp bonded until after first engine run)
11. Brake lines from park brake valve to calipers
12. Throttle and engine throttle (capture) bracket

Once all that is done, its off to the airport.  Hoping for mid 2023, then its onto final wing integration (wiring, fuel lines, hatch covers, wing tips, lights) and final wiring, etc for the tail.

80% done, 80% to go.  Will be finished on Tuesday.  Just not saying which Tuesday... 

Control Sticks

I am at that point in the build where progress is frustrating because I have overcomplicated a lot of things.  I decided to go with the Infinity Stick grips, and load up on functions on the grip itself.  They are a really good grip it a lot of ways.  Easy of installation and wiring is not one of them.

Well, thats not fair I guess.  The installation is fairly straight forward... but you have to trim 1" off the stick to get it to fit under the panel, drill a big hole for a plastic bushing, and a slot for the wiring to pass through.  But it nicely clamps onto the stick...

First things first... you need to set the fore / aft position of the stick.  That means you need uphostery (which I ordered) first, then the sticks have to be drilled to the yoke.  This is the part I have been avoiding because I was unsure how to tackle the issue.  Since I have the fuel lines installed, you have to work around them.

So today after (what seems like months) of indecision (and talking to other builders), I tore into it.  The holes have to be drilled through the yoke and stick, but I couldnt get my alignement jig on the yoke, so that means freehand drilling, which is prone to errors, plus you have to line up the sticks and I dont have the wings attached to center the ailerons.  But, there is some adustment on the yoke, and turnbuckles.  So I decided to just center the yoke with some wood blocks, center the sticks with a board (per the manual), and carry on bravely.

After marking 3/8" in from the yoke weldments, I drilled 3/32" pilot holes through the top only (yoke and stick) and clecoed them in.  That should hold everything in place.

I dont have the right length drill bit for the forward hole, but did for the aft (again, working around the fuel lines).  So both aft holes were drilled and a AN3-14 bolt dropped in replacing the cleco.

With the right length bolts I can proceed.

To the wiring.  UGH.

The infinity grip the following options:

• 4 way hat switch
• Trigger switch
• Left and right thumb switches
• Middle thumb switch
• Pinky switch

After thinking a lot, and consulting the forum I decided on the following:

1. 4 way hat switch:  Pitch and roll trim
2. Trigger switch - Push to talk
3. Left and right thumb switches - Left(a):  Autopilot disconnect / CWS.  Right(b):  Momentary toggle - forward, COM1 flip flop.  Aft - COM2 flip flop.
4. Middle thumb switch - Audio panel swap from COM1 to COM2 and vice verse.
5. Pinky switch - Transponder IDENT

That equates to a whole bunch of wires.  Items 1, 2, 3a are handled by the ACM wiring to the 'control stick' port.  Items 3b, 4, and 5 need to be wired directly.  The transponder IDENT will be handled through the ACM using a general purpose input.

Here is the wiring diagram for just the sticks.

This is not going to be fun.  10 lbs of poop in a 2 oz bag.

Grips mounted to the sticks after drilling.

Sticks fully drilled, ends cut and filed, grips mounted and wires fed through.

The Infinity Stick Grips are very nicely made, as assembled really well on top of the stick.  After about 15 disassembles / reassemblies I am reasonable good at it.  The issue is the wires... there are so many wires, and if they get caught in the channel for the stick, or against one of the bosses that the screws go through it wont go together.  If any little thing is wrong, you are taking it all apart again. If you want a grip that you just mount on the top of a stick, this is not the one for you.

Next is to connectorize the cables from the sticks and integrate in the ACM, Dynon Radio, Audio Panel, etc.  I thought I had enough connectors, pins and housings, but apparently not.  Ordered from Digikey today.

Connectorizing was not fun (I have an aversion to connectors anyway, specifically getting pins out of shells - never goes well).  There is a colour code for the wires, but there are duplicates.  For the most part, black is ground (but not always), and there are multiple red and blue wires.

1. Sorted through all the wires and found the ground (using an ohm meter), and separated them from the pack
2. Tied all the ground together on the stick side using solder sleeves.  There are 6 ground - so 3 into 1, then 2 into 1, then that wire went to the connector.  Sleeves are hidden under head shrink.
3. Checked functionality of every switch at all points in the process.  Would really suck to get everything done and have a busted wire or bad ground.
4. Connectorized the end using a d-sub 15.
5. The connector will fit through, but without the shell, and it has to go through sideways.  I left enough bare wire to get it through.

Onto final wiring.  I have the ACM harness for each stick, but it doesnt come with IDENT, COM flip flops (x2) and Audio Panel swap.  These all have to be added to the harness.

So I cut open the pilot side harness, and added the 3 wires.  Oh what fun...

These 4 wires need to go to various places:

• IDENT:  Goes to a PFD input on the AC Rear Connector
• COM 1 SWAP:  Goes to the Dynon radio
• COM 2 SWAP:  Will go to the yet to be purchased GARMIN NAV/COM
• Audio Panel SWAP:  Goes directly to the Audio Panel.

I put everything together to test, and it all worked - except the Audio Panel COM SWAP.  It seemed like it would work every once in a while, but not like I expected.  I checked with both PS Engineering, and Advanced - but at the end of the day I just miswired it.  I had it connected to pin 21 on J2, when it should have been pin 20.  The issue was getting the connector apart on the audio panel without losing any hardware in the fuselage or panel.

To finally everything is done.  Sticks are wired, connectors attached, everything tested good.  Sticks are bolted in place.

Starting on the cleanup now.  It sure needs it.

BNC Connectors

I have an aversion to all connectors.  They always seem to make my life hard, and I mess things up and cannot get them apart.  The top of the list has been BNC connectors, because I didnt understand them.

A buddy of mine showed me how to put on a BNC, and still I messed them up.  You have to strip 3 times - center conductor, inner jacket, outer jacket - I get that - but how long does each of them need to be?

I have 3 types of connectors for the Sportsman

• BNC Male
• BNC Female Bulkhead
• TNC Male

I found it extremely hard to find the correct assembly instructions for each type of cable.  After searching, I found it for the Amphenol BNC male and TNC Male, but not the BNC Female Bulkhead.

So I measured everything and mapped it out (BNC Female Bulkhead).

Dimensions are available if you have the part number.  Below is the Amphenol TNC male.

This may be 'old hat' to some, but i was just inexperienced - and after wrecking some pins I thought there has to be a better way.  Now I can do a BNC and not waste any parts.

Happy days.

CANbus / UL Power Integration

Finally got around to wiring the Dynon EMS-221 to the UL ECU.

The Dynon manual does not give a lot of detail, except the pinouts - and there are omissions.

Here is what came with the engine and harness:

On the EMS side, the manual gives some info on UL Power installations, but it is not overly helpful.  However, I asked Advanced specific questions about the ground wire, 120 ohm resistor, and shield from the UL side.  Below is what I got back.

This is what I followed.  I added the termination resistor (however, Advanced noted that they probably have many Rotax installs in the field with no resistor, and no issues), ground, and tied the shield to the EMS ground.

When I fired everything up, there was no obvious was to see the CAN bus status.  I poked around forever and nothing was obvious.  I had a 2AM brainwave that I needed to change the engine selection.  My PFD was set to '6 cylinder turbo', when it should have been 'UL 6 cylinder turbo'.  As soon as I changed that, I now had the option to select CANbus inputs for the different gauges and I could see that CANbus was connected and working.

As you can see, there is an OIL PRESSURE A and OIL PRESSURE B - where A is valid, and B is not.  I assume B is for if you have a 2nd ECU.  Confirmed on 12/6/2022 that the 'B' lane is for a 2nd ECU..

Everything appears to be working.  I have to set the limits on everything still, but that can wait until closer to first engine start.

UL Power - ECU Wiring

I thought the UL ECU wiring would be simple, and in some ways it is simple.  But as always, the devil is in the details.

Power:  The ECU has 6 wires that all need to be attached to an ECU switch.

Ground:  The ECU has 5 wires that go to ground.

FPCR (Fuel Pump Control Relay(s)):  The ECU can control the pump(s).  I opted to do so, but there is a 2nd bypass circuit around the relays just in case.

Ignition:  Circuits for left / right or 1/2 coils to switches (or a standard key switch).  Grounded they are OFF, open they are ON - just like a mag.

Aux box:  Provides ambient pressure.  Plus other things, but this is all I am using it for.

Boost controller:  Control line from the ECU to the Boost Controller, plus power and ground.

CAN-bus:  Data lines to grab engine data via CAN.

RS-232:  Separate RS-232 connection for an EFIS feed, or to use the UL-READ software.  I need to order this cable.

Discrete engine inputs:  Separate inputs for Engine RPM and fuel consumption.  I am not using these, as they are provided over the CAN-bus.

Dummy lights:  2 LED's.  1 for 'check engine' (which indicates a sensor fault), and 1 for 'low battery'.  I planned for both of these in the panel.  The ECU only provides a ground to activate these LED's, power is separate.

The above is the basic lay of the land.

Current schematic below.

At present, everything is wired except the key switch.

The challenges:

• The ECU is mounted on a tray forward of the instrument panel.  If it needs to be removed, take out the MFD, remove the two harnesses, loosen the bolts and its free.  You should be able to do all this sitting upright in the seat.
• Making the above happen is a challenge.  I had to route all the wires in two consistent bundles (one firewall forward, and one for the cockpit interconnects) and not running in 4 different directions.
• To do so, I fabricated some wiring 'braces' that everything is tie wrapped to.  But its all very condensed. Hopefully this works out.

Progress:

• Everything is wired for the ECU, and it powers up (the LED's flash upon startup).
• The next big step is to see if the ECU connects to the CANBUS on the EMS221.
• The wires are not in their final position.  I want to make sure everything works before doing the final tie wraps (hence no pictures, it looks pretty ugly right now)

What's left to wire:

• Magnetometer:  Cable is run, but needs to be shortened (ordered it too long)
• Fuel tank probes.  Wires to the EMS, needs to head out to the wings.
• Sticks:  Sticks themselves are wired, just need to route them and connectorize from the ACM (plus the pull downs from the audio panel, com, and ACM aircraft rear connector
• RF / antennas:  VOR, 2xCOM antennas.

Probably forgetting something, but its almost there.

TO/GA Button

I had figured I would eventually figure out where to wire the TO/GA button (Take Off / Go Around).  That never happened, so I needed to ask Advanced.  Well, that feature is not available yet - coming in release 17 (current release is 16), with no planned delivery date that they would commit to.  Well I am not ready to fly yet, so no big deal.

The button needs to be wired to one of the PFD inputs on the Aircraft Rear connector:

From the Advanced Manual:

Will use PFD2, pin 14.

I was really nervous about opening up my AC Rear harness, but of course it was a non issue and took 2 minutes.

Last step is testing it, but that will have to wait until the displays are back in.