March 2011 Archives

Dynon and Vertical Power this morning announced that the SkyView system will be supporting the VP-X.  After seeing the VP-X at Oshkosh last year, I decided to defer working on the electrical system as long as possible in the hopes that this will happen.  Thanks Guys; this combination is going to rock!

Here's the announcement from Dynon:

It's a little disappointing that they're charging an additional $275 for this given that they'll almost certainly sell more SkyView systems as a result and because every other avionics supplier is including it for free.  Dynon products are already priced much more aggressively than their competitors though, so I'm not going to complain too loudly.

Here's an overview of the VP-X:

After working through the load planning, I'll be going with the VP-X Pro.  Using the VP-X should not only simplify wiring, it should provide substantial new features to the electrical system as well as advanced fault detection.

Now, if Garmin would just announce a replacement for the GNS-430...
I fabricated the exhaust stabilizer strap tonight out of some aluminum angle that I cut one leg off of.  I primed and painted it and will install it tomorrow.  This ties each pair of pipes together at the back end so that they all move as a unit.

I installed the exhaust stabilizer strap that ties the two pairs of exhaust pipes together.  This significantly stabilizes the exhaust pipes over just having each pair supported by on hanger.

Construction work is slowing down on the plane a bit while I'm working on the electrical system design.  The VP-X is fairly significantly different than the architecture specified in the Aeroelectric Connection.  I'm reworking most of the schematics and still trying to decide how I'm going to handle backup circuits for several devices.
The stock throttle bracket that Van's supplies doesn't work with the Superior sump since the attach point is in a different location.  I'm going to fabricate a custom bracket out of some 16 gauge steel (the same thickness as Van's bracket).  I used some really thin (0.004") aluminum flashing I had on hand to mock up the bracket.  This puts the cable on a direct path to the hole in the firewall and keeps it well clear of the exhaust and sump.

Here's a shot from slightly lower in case that makes it more clear.

Here's what the rough bracket looks like.  I unfolded this and traced the pattern onto some 16 gauge stock I picked up from Home Depot.  Cutting it out will be easy, but I'm still not quite sure how I'm going to bend this.

The throttle bracket that I mocked up a couple of days ago had an extra bend that was unnecessary and I couldn't figure out how to bend it using the tools I have.  Instead, I mocked up a simpler bracket.  The slot on the end was only to make it easier to fit while mocking it up.

I unfolded the prototype and transferred it to a piece of 16 gauge steel.

I marked out the bends and bent them using this vise brake that I borrowed from my dad.  This thing had no problems bending 16 gauge steel.

I drilled the mounting and cable holes and temporarily mounted it to the engine.  Unbelievably, I absolutely nailed it on the first try.  The 1/4" mounting holes perfectly lined up with holes on the sump and the placement and angle of the cable hole was spot on.

Here's a closeup of the mounting end.  This picture makes it look like it comes pretty close to the exhaust pipe, but there's quite a lot of clearance.

After some adjustment, here's the throttle in the full open position.  Notice the slight gap between the nut behind the throttle nob and the friction control.  This ensures that the throttle arm hits the stop on the fuel injection servo which ensures that you can reach full throttle.

Here's the throttle in the full closed (idle) position.  Again, I'm hitting the stop on the fuel servo which ensures I've got the throttle fully closed.

This is a poor picture, but it shows the alignment between the throttle cable and the hole in the firewall.  It's a perfectly straight shot back to the firewall from the bracket and clears the heat muff inlet by a 1/2" or so.

Now that the throttle bracket fits correctly, I can clean it up and powder coat it before installing it for good.
I got an email from Joe Blank at Van's today.  After reviewing my cowl fitting issue further, they now think my cowl is made correctly and that if I trim the aft edge all the way around, I should have enough overlap on the sides to make a straight joint.

Anyway, tonight's little project was to determine the mounting position for the control cables.  I used the stock bracket that came with the kit to mock up a potential control spacing to see if there were any conflicts before drilling the actual bracket that I bought from Experimental Air.  My original goal (and what I mocked up here) was to put the three engine controls in the center, the parking brake on the left and the cabin heat on the right.  This resulted in 2" between the outer knobs and the outboard engine controls and about 2 7/16" between each of the engine controls.  After playing with it for a few minutes, I decided that this was too tight and that the cabin heat knob should be removed from the bracket.

As you can see, I also moved the parking brake knob over to the right side of the bracket so that it's out of the way.  This also has the advantage of bringing the engine controls closer to me.  The three engine controls are spaced 3" apart and the parking brake knob is a hair over 2 1/2" from the mixture knob.  You can also see that I drilled the holes lower than the center of the bracket.  They're 3/4" up from the bottom edge which leaves plenty of room to provide labels for each of the controls.

A top view shows that my hand has plenty of room when operating each knob.

I fabricated the 0.020" spacers for the hinges that attach the bottom of the cowl to the firewall.

Next up, I cut and drilled the hinges to the firewall.  The plans call for the same 1/8" aluminum hinge stock that is used along the sides and top of the firewall, but this is an area that is subject to high vibration and it's quite common for eyelets to break off of the aluminum hinges here.  A number of builders have switched to stainless steel hinges and this appears to have cured all of the problems, so that's what I'm using.

After deburring everything and priming the aluminum spacers, I riveted the hinges to the firewall flange using the hand squeezer.  I was able to reach all but the outer two rivets on each side.  I'm going to have to shoot and buck these, but the access is really tight due to the engine mount.  I'm going to have to find something really thin to use as a bucking bar.

I installed the other half of the hinges using the included hinge pin.  The fit is really tight, so it took a bit of work to get the pin in.  I'll try lubricating the pin to see if that helps.

I only had a little time in the garage tonight, so I decided to drill the canopy side skirts, mostly to get them off my bench.

Here you can see that the front joint is aligned with the downward bend in the longerons.  Since the canopy rails aren't yet riveted down, there is a gap here that I'm hoping will go away once everything is riveted together.

Here you can see that I left the side skirts a little long so that they can be trimmed to perfectly align with the skin that surrounds the rear window.

I got an order from Aircraft Spruce today with some shielded 22AWG wire.  I soldered the inner wire to pin 6 of the lightspeed input connector and the shield to pin 13.  I then slipped inner and outer pieces of heat shrink over the wires and shrunk everything in place.

Also in the order was some 2" scat tube and some 2" hose clamps.  Here is the hose from the output of the heat muff up to the heat box on the firewall.

Here is the hose from the back of the baffles down to the heat muff.  I'm not sure if I need to secure this at an intermediate point or not; I need to do a little research on that.

I installed the alternator wire today.  This is 6AWG wire which is slightly larger than what is needed for a 40A alternator (8AWG would be fine), but there's a possibility I may swap this out for a 60A alternator at some point, so I went ahead and ran 6AWG.  Here's the connection at the alternator end.  A terminal has been crimped on, then heat shrink over that to act as a strain relief, then a boot over that to keep the hot lead protected.

I anchored the wire to one of the sump bolts where there was already a longer bolt for the prop line.

Here you can see that the line is anchored in two more places before connecting to the shunt.

After finishing up the alternator cable, I resumed work on the canopy side skirts.  I pulled the canopy and frame off of the plane and drilled the #27 holes for the #6 screws, then deburred, dimpled, and countersunk all the necessary holes.

The plans have you fabricate a boring, angular canopy lift handle and then rivet it to the outside of the canopy frame.  I thought it looked cheesy, so I'm deviating a bit here.  First up is to round the handle nicely instead of just chopping the corners off.

I then cut a slot in the canopy skirt and frame.  This will allow me to mount the handle on the inside and only have the horizontal piece be seen from the outside.  I made the initial slot with the cutoff wheel in the die grinder and then used needle files to get it perfect.

I then clamped the handle to the inside of the canopy frame only.

And drilled the frame to the handle.

After deburring, countersinking, and priming the mating surfaces, I riveted the handle to the frame only.

Finally, I installed the skirt and riveted in to the frame.  This looks so much nicer than the handle specified in the plans and only took about an hour to do.  While I was working on the side skirts, I rewatched (mostly just listened to) Evil Dead III: Army of Darkness for about the 20th time.  That is such a fucking awesome movie; Bruce Campbell rocks.

In preparation for installing the canopy bubble to the canopy frame permanently, I needed to pain the glareshield a flat black so that there won't be any glare on the inside of the canopy.  I scuffed the surface with scotchbrite and cleaned it thoroughly since this will be nearly impossible to repaint later.  I then primed it and painted it.

Here's the finished surface.  Other than a couple of minor boogers, it looks good.

I spent the rest of the night trying to tweak the canopy frame to follow the curve of the fuselage.  The left side was overhanging the side about 1/16".  I used my stretcher to stretch the canopy channel and unfortunately, way overshot it.  I tried using the shrinker to pull it back, but ended up breaking the shrinking dies in the process.  I finally had to use my vise and a contraption of parts to bend the frame back into alignment.  It was a major pain in the ass, but it looks pretty good now.

Finally, I pulled the canopy bow off the plane and drilled the splice plate.

I ordered a bunch of small (10x16mm) LED lights to build an annunciator panel with.  The colored plastic covers can be popped off and labels can be placed underneath to indicate the condition that is being annunciated.

The last time I spoke with Brett at Bonaco, he indicated that they now have black anodized fittings, so I ordered replacement AN822-3D fittings and new hoses from the reservoir to the master cylinder with black fittings on each end.  This looks so much nicer now that everything associated with the brakes and rudder pedals is black anodized aluminum.

I torqued down all of the fittings and decided to fill the brake system tonight.  I'm using Royco 782 fluid.  I was able to find quart sizes of this at

Royco 782 is a MIL-PRF-83282 fluid which is the replacement for MIL-H-5606 and has a much higher flash point.  There have been brake fires with MIL-H-5606, so I didn't want to use that.

The general consensus seems to be to use a pressure system to fill the brake system from the bottom, but people sometimes still have issues with bubbles in the system.  Getting the bubbles out of the system has nothing to do with the direction you fill the system, it's all about getting a high flow rate through the system.  If the flow rate is too slow, bubbles will get stuck in high spots in the system since they tend to migrate fairly slowly through the narrow lines.  With a high enough flow rate, the bubbles can't help but be carried along with the fluid.

Instead, what I did was create a closed system to pump the brake fluid through.  I hooked up a fitting and hose to the brake fluid reservoir and put the other end in the can of brake fluid.  I then hooked up another hose to the fitting on the bottom of the wheel caliper and also put that hose in the can of brake fluid.  Now, as fluid is pumped out of the can and through the system, it's returned back to the can.  All I had to do after that was operate the brake pedals fully and moderately quickly until nothing but clean fluid was being pumped back into the can.  This only took about 30 seconds on each side.  The brakes are absolutely rock solid and no leaks!

I primed and riveted the canopy bow together.  One of the rivets intersects a tooling hole, but I'll fill both of these with filler anyway.

I clecoed on the canopy bow and then drilled the latch lugs to the canopy frame.  There is very little room to fit these, so Van's basically has you just guess where to drill the holes and then cheat them over if you guess wrong.  I didn't like that approach, so I slipped the lugs in from the bottom and then engaged the latch to define the lug position.  I then ran the drill bit through one of the holes in the weldment to mark the lug.  I then removed it and center punched along the scratch and drilled to #40.  I reinstalled the lug, held it vertical and drilled the second hole.  This worked perfectly and the lugs seem to be in just the right spot.  Finally, I reinstalled the struts and raised the full canopy frame for the first time.  Without the canopy, the struts nearly eject the canopy frame from the airframe.

I temporarily installed the canopy to see how it affected opening.  With the extra weight of the canopy, it opens nice and smooth.  You really have to manage it coming down though since it hits the neutral point about 12-18" up and will slam down it you're not careful.  I'm also going to have to add some guides that help align the lugs with the holes in the side rails.  Without that, it's too easy to have the canopy come down slightly cocked and have the lugs hit the top of the side rails.

Finally, I spent about an hour inside the cockpit.  I put down enough padding to simulate the thickness of the seats to see how much head and knee room I was going to have.  I also tried the control bracket to see how it affects my knee room.  I ended up biasing it to the right so that the prop control is centered on the panel.  This will give the passenger less knee room, but they're not flying so it shouldn't be that big of a deal.  I also spent a bunch of time thinking about the placement of switches, buttons, etc. on the panel.  The radio stack will be centered with the SkyView displays as close to the stack as I can mount them.  This should leave room on the left for a TruTrak Gemini and some switches.  There will also be some switches below the SkyView displays and a few other odds and ends on the right side of the panel.  I'll lay this out more precisely eventually.

No pictures tonight, but I worked on getting the canopy to close more smoothly.  I then spent a little more time working on the panel layout and put in an order for some electrical goodies from B&C.
I stopped by the hobby shop tonight and picked up some small 4-40 threaded rod and some threaded clevis ends to connect the flap arm to the Ray Allen position sensor that will feed the flap position to the VP-X.  I stole the dimensions from Mike Bullock's site and they worked perfectly.

I fabricated a small clip that bolts to the adel clamp to connect the clevis to the flap rod.  I used a piece of 0.063" angle with one leg mostly cut off.  This wraps around side of the adel clamp flange and will prevent it from rotating.

Here's the other end.  I didn't tighten the nut fully since it interferes with the nut on the clevis.

I turned the screw around on the clevis and tightened it more fully.  I ended up also having to use one of these tiny lock nuts to provide clearance from the clevis screw.

The SkyView DB37 connector comes with a long USB cable with a type A female end on it.  The other end connects to pins 16-19 on the DB37 connector.  This cable is kind of useless as the female end can't be mounted to anything.

I extracted these pins from the DB37 connector so I can replace it with a more appropriate connector.

I picked up this 18" USB 2.0 A M/F panel mount cable.  I could have just connected this to the preinstalled SkyView USB cable, but it won't have been extremely long and would have just ended up coiled up behind the panel.  I clipped off the male end and crimped on some d-sub sockets.

I then reassembled the connector.  I really wish Dynon had just installed this sort of cable in the first place.

Here you can see that the cable is long enough to reach anywhere near the SkyView screen.  To confirm everything was working correctly, I upgraded the SkyView to 2.6 using the USB thumb drive plugged into this cable.  I'll install an identical cable on the other SkyView screen once I order it.

While I had my electrical tools out, I went ahead and soldered some lead wires to the controls that will be installed in the control stick grips. 

Before I can install the controls in the stick for good, I wanted to put a couple of coats of tung oil on the grips.

After soldering all the wires to the control stick switches, I slipped some expandable sleeving and finished the end with heat shrink.  This is the copilot's PTT button.

The copilot's stick is removable, so the PTT switch needs a connector in it at the joint in the stick.  I'm using a small 0.062" 2 circuit plug.  The wire will exit between the rod ends at the bottom of the stick.  I added a layer of heat shrink around the sleeving where it passes between the rod ends to provide an extra measure of abrasion resistance.

I drilled both control stick grips and epoxied in some small 8-32 t-nuts.

I then installed some 1/4" long socket head set screws that will be used to anchor the grips to the sticks.

With all of the wire soldered on the switches and buttons, I installed them in the grips.

I slipped some sleeving over the nine wires coming out of the pilot's grip and then installed it on the pilot stick.  Just like on the copilot's side, I routing the wires out through the bottom of the stick.  Many builders drill a hole in the side of the stick near the pivot point to avoid routing the wires near the moving parts, but Van's recommends against this as it will weaken the stick.

Just like on the copilot's side, I installed a length of heat shrink where the wire bundle passes between the rod end bearings.

I'm planning on having 7 or 8 annunciator lights.  Some will be triggered when a signal is pulled to ground and others when a signal is pulled to 12V.  I also wanted a button to test all of the lights and a dimmer so I can reduce the brightness for night flight.  I couldn't find an off the shelf controller that I liked, so I decided to dust off the old EE degree and design a simple circuit that did what I want.  I prototyped a two light version of the circuit below.  You can sort of see the two lights (red and yellow) near the top center of the picture.  The left switch at the bottom simulates the push-to-test button.  When thrown, both lights should light up.  The right switch simulates one of the circuits that should light an annunciator light when pulled to ground.  This circuit doesn't handle signals pulled to high because I didn't have any diodes on hand to do that portion of the circuit.

Here's the push-to-test switch thrown.  You can see both lights are on.

Here's the single signal light illuminated.  The lights only require 20mA at 12V, so a simple 2N2222A TO-92 NPN transistor can handle this without even warming up.  The end circuit only needs one diode, one resistor, and one transistor per light.  There's one additional resistor in the circuit to handle one edge case that could blow a diode if one of the high signal pins were pulled to ground accidentally.

I've spent the last couple of days refining the annunciator light circuit and laying out a PCB that I'm going to have fabricated by  They require a minimum order of three boards, so I'll have a couple of extra if anyone wants to buy them.  Email me at the address in the left bar if you want one.

I also designed a couple of other simple PCBs to replace the SkyView splitters as well as the interconnect between the SkyView and the other avionics.  I'll post pictures of the boards when I get them.

Unfortunately, the PCB design software only runs on Windows and is really shitty.  I haven't had to use Windows this much in almost 10 years, but it was just as bad as I remember.
I ordered three of the solid state dimmer circuits from Perihelion Design.  They're completely self contained and use a LM317T chip to regulate the voltage to the lights.

The zig-zag trace that connects the outer two pads regulates the minimum voltage.  With this short, the dimmer puts out 1.3V at the low end.  This is too low for the annunciator and cabin lights I'm using.

I broke this connection so that I could solder a more appropriate resistor in place of this trace.

The cabin light needs a 330Ω resistor to set the low end of the voltage range to 5V.  Below that, the cabin light I'm using shuts off, so there's no point in letting the dimmer go below that voltage.

The dimmer that controls the annunciator lights needs a 150Ω resistor to set the low end of the voltage range to 3V.  The third dimmer will be used to dim the lights that go under the glareshield.

Heres where I mounted the light.  It's basically as far forward as I could mount it without interfering with the roll bar.  This is still low enough that it illuminates the whole panel, but far enough forward that I can illuminate my lap reasonably well.  This can also be turned left-to-right as well as angled up and down.  I'll most likely wire this directly to the battery bus so that I can use it to illuminate the cabin and baggage area when loading/unloading the plane.

Lots of Random Tasks

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I zip-tied the EGT and CHT wires to the ignition wires on both sides.  These are just temporary, but I need to get the wires in their final positions so that I can begin cutting things to length.

I then installed the 1/4" nipples into the EI FT-60 (colloquially known as the "red cube").  This will be mounted between the fuel injection servo and the spider and will measure the fuel that's being delivered to the engine.

Here's roughly where it will be installed.  I will need a 2 3/4" hose that connects the fuel servo to the input side of the red cube.  Hopefully Bonaco can make one this short.

The output side of the cube has a 90º elbow that points directly at the inner end of the right-side intercylinder baffle.  I'll drill a hole through there to pass the hose that connects the red cube to the spider.

I also removed, re-lubed, and reinstalled the fitting in the spider so that it points straight down.  The shiny area between the cylinders is the intercylinder baffle where the hole will be drilled.

I removed the right side intercylinder baffle so that I could drill the hole.

I drilled a 13/16" hole...

...that will hold a grommet that has a 1/2" interior hole.  That is roughly the outside diameter of a 1/4" hose with firesleeve.  I'll have to install the grommet over the hose before installing it in the hole, but I wanted to make sure it fits properly.

I stopped by OSH and picked up some #10 brass hardware and installed the SkyView ADAHRS.  The ADAHRS contains a magnetometer, so there can't be any ferrous metal near it so that it can get an accurate heading reference.

I crawled back in the tailcone (hopefully for the last time) to install the static tubing from the tee on F-708 (near the bottom of the picture) through F-707 and into the front of the ADAHRS.  There is a tee installed here because the static line will also run forward to the TruTrak Gemini that I'm using as a backup EFIS.

One of the things I got in my last order from B&C is the alternator field connector.  I installed a jumper between the terminals and added some heat shrink.

I added a couple of extra pieces to build up the thickness of the single wire.

Then installed a larger piece of heat shrink over the whole thing.

Here's where it connects to the back of the alternator.

The wire will likely run along the alternator b lead along with the wires for the fuel flow sensor.

I installed some one leg nutplates on the SkyView EMS box because I need to install the screws from the other side in case this box ever needs to come out.

I then installed the EMS on the outboard side of the subpanel support rib.  You can see here why I needed to install the screws from the other side.  The top skin curves down here, so there would be no room to get a screwdriver on these screws if they were installed from this side..

I also installed nutplates on this side to attach the lightspeed ignition box.

Here's the Lightspeed ignition box.  You can see the screws that attach the EMS just above this box.  There is another pair just below the ignition box.  These are all reachable without removing the ignition box.  There is just enough room in front of the ignition box for the RG-400 wires to curve downward to run along the top firewall stiffener without contacting the firewall.

I didn't like the strain put on the ignition wires by the tight bend necessary to curve down toward the top firewall stiffener, so I picked up a couple of right angle BNC adaptors from Fry's.  These were only a few bucks each vs. the $17 each (plus shipping) for right angle crimp connectors.  This creates an extra connection in each line, but they're on quite solid, so I'm not worried about it.

I received my Vertical Power VP-X empty shell today.  Instead of using the included mounting brackets, I cut a couple of pieces of 0.063" angle so that the VP-X could be mounted to the bottom of the two subpanel ribs.  This location will create plenty of room on each end for the connections.  It's high enough that it won't interfere with the control cables, but low enough (and forward enough), that it shouldn't interfere with any radios that poke through the subpanel.  The forward mounting angle is 1 7/8" aft of the top firewall stiffener, which provides plenty of clearance for the parking brake valve arm.  You can also see in this picture that the ignition wires fall naturally along the forward mounting angle (now that the right angle adaptors have been installed).  I'm likely going to use that angle as an anchor point for a forward wiring bundle.

I drilled and attached the mounting angles to the VP-X.

After cutting the angles to length and drilling them to the subpanel ribs, I installed nutplates on the ribs and reinstalled the VP-X.

Here you can see the nutplates that are used to anchor the mounting angles.  This is *very* strong.  The actual VP-X (as opposed to the empty shell) weights 2lbs.  There might be as much as a pound or two of other stuff hanging off these mounting angles.  Even at 6 Gs, that's no more than 25lbs or so.  This can easily hold twice that, so there is plenty of margin built in to this.

I'm having my interior done by Classic Aero Designs.  I really want to go with the Aviator seats, but I had some concerns about the amount of headroom I'd have.  I spoke with Luke at Classic Aero and he offered to send me out both an Aviator and a Sportsman seat so I could try them out.

The Aviator seat has a rounded top and an integral frame.  It's also offered with a headrest and looks much more like an automotive seat.

Since it has an integral frame, the back is covered and has a pocket.  There is also an adjustable lumbar support.

The Sportsman seat has a square top (because it uses the Van's seat back which has a square top).

It also has an adjustable lumbar support, but the back must be un-velcroed from the frame to adjust it.

I installed a couple of nutplates on the B&C voltage regulator and installed it to the right subpanel rib.

There are two bundles of wires on each side of the VP-X that need support.  I also need a way to route wires between the left and right side of the aircraft.  I installed some adel clamps on the bottom of each subpanel rib.  They're just clecoed on since I'm sure I'll have to swap them out for different sizes after I know how many wires will run through each clamp.

It's not clear from this picture, but they're aligned with each set of connectors on the VP-X.

I also installed a couple of adel clamps on the forward VP-X support angle.  Wires that need to cross from one side of the plane to the other will step up and cross on to of the VP-X through these adel clamps.

Here you can see that the ignition wires cross over the VP-X, down through the forward adel clamp below the subpanel rib and then out through the firewall pass-through.  Once these are zip-tied to all the other wires running along side them, these will very well supported.

EMS and Ignition Wiring

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I removed all of the unused wires from DB-37 connector on the SkyView EMS.  I ended up taking out a couple more after this picture was taken.  This was a surprising amount of weight that I don't have to haul around without benefit.

Here's the remaining wires.  I'm only using about half the pins in this connector now.  Part of the reason is that all of the position sensors (aileron trim, elevator trim, and flaps) now connect to the VP-X.

I noticed that one of the BNC connectors on the Light Speed ignition box was loose.  I probably violated the warranty (which is likely expired now anyway), but I popped the cover off to tighten it up.

Here's the connector in question.  You can clearly see that the lock washer isn't even compressed.  They simply forgot to tighten it fully at the factory.

By comparison, the other BNC connector was tightened fully.  Now they both look like this and are rock solid.

I decided to reroute the ignition sensor wire so that it takes a more direct route back toward the firewall.  This also keeps the wire away from the snorkel (not yet installed).

The wire follows the starter wire back to the engine mount then will get anchored where my finger is so that it will not interfere with the oil cooler.

It then turns up and follows the CHT/EGT wires through the firewall.  It was a pain getting the connector through the pass-through.  I had to remove most of the other wires as well as the connector housing to squeeze it through.

From there, it follows the manifold pressure back and through the aft adel clamp.

Both then turned upward and connected to the Light Speed ignition box.  You can also see a red and black wire running through the right adel clamp.  These are the wires from pins 1 and 3 of the EMS.  The red wire connects to the battery bus and the black wire connects to the firewall ground block.  Together, they're used to measure battery voltage as well as provide a small amount of power to a couple of the engine sensors.

Both wires run along side the ignition wires.  The black wire then separates here and connects to the ground block.  You can also see that I connected the two VP-X ground wires to their appropriate pins on the J10 and J12 connectors.  These are 18AWG (vs the 22AWG from the EMS) since they carry power for the flap and trim motors which can draw several amps.

The red wire continues on through the front adel clamp and connects to the battery bus.

The label maker I'm using can print on heat shrink tubing.  I'm using that to label certain wires.  All ground wires in the plane will be black, so there's no need to label them.  All power wires will be labeled as well as both ends of signal wires.

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