Friday, September 14, 2018

Antennas


Installations of the antennas was bumped to the top of my punch list after I was told that I shouldn't power up the avionics without them. I was going to push this off until I had the wings on and what not but instead I decided to go ahead and do it.  This will allow me to test out things in my driveway, so maybe it's best that way.

I'm not sure I realized just how many antennas I was going to need to mount all over the plane.  It's very much dependent on what you're throwing in there and since I'm doing a full glass panel with several redundant components I knew I was going to need to do some placement planning. For my set up I needed the following antennas; 2 for radios, 1 for ADSB, 3 GPS pucks, NAV, a magnetometer and then of course on for the ELT.  That's 9 antennas that I had to figure out where and how to mount.  There's certain spacing and installation parameters you need to consider.  I originally wanted to shove most everything in the tail minus the NAV antenna that's out in the right wingtip. I have to wait until the wings are on to install the NAV and I'm still debating on how and where to install the ELT antenna, so I'll do those later.

Doublers

Obviously when you install antennas you end up cutting up to 3/4 inch holes into the airplane skins.  Doublers are typically suggested but not required.  My 172 had GPS pucks with no doublers and never had an issue.  But since I tend to overbuild so I wanted to go ahead with doublers for all antennas.  Making them wasn't an issue, for the GPS pucks I actually had a factory made one that I was able to replicate, and then using some ideas online make them for the rest.

Attaching them is a different story.  I've seen some elaborate rivet patterns which frankly look like drilling, dimpling and two person rivet driving.  I read that the rivets actually help with the strength, but that guy was using metal the same thickness of the skins (thin).  I decided to go thicker metal and use 3M aviation two part epoxy to secure in place. I also went ahead and primed the exposed side.  In the end these things aren't going anywhere, the skin is thicker and it adds to the rigidity.

Here's a picture showing my GPS puck doublers.  The one on the left is from Garmin, the other two I made.

Comm antennas

Not surprisingly there are a number of strong options on how and where to place your comm antennas.  The two schools of thought is you should put one on top of your tailcone and the other on the bottom.  This would prevent any shadowing or possibility of dropped comms.  Then you have the other group that prefers to mount both antennas on the bottom, either the front or read seats.  The idea is shorter runs, a bit out of the way and suitable.  I've read plenty from both sides and my conclusion is people have been successful installing either way so I needed to pick what will work best for me.  My tailcone is pretty cramped so I decided under the back seats was the way to go.

First I needed some way to access these.  I had seen people use the Vans wing access panels but those are pretty big.  All I needed was enough space to get my hand in to do the initial installation and any future maintenance.  Luckily I have baby hands so it will fit between the ribs fairly easy.  However you don't want a gaping hole beneath your seats and still need a way to cover it.  I just went head and essentially made a door on some hinges.



For this doubler I didn't want it over the rib piece.  So decided to go ahead and epoxy the piece in there first and then drill the mounting holes.  This saved me the trouble of trying to match holes, just slap it on and let it cure.

Once it was cured I drilled out the holes based on the gasket I received and used drawn lines to center.  Then it's just a matter of bolting on the CI 122 VHF comm antennas, one each side.  Two person job to tighten and to torque I had to do about 8 inches of extensions to reach the nuts.



ADSB

Hmm, I didn't take any pictures but I went with the CI-105 and I mounted it under the copilot seat, basically centered and making sure it's not hitting any brake or fuel lines.  I also made a doubler specific for this antenna.

GPS

I have two GA 56's for the G3X and G5 and a much larger GA 35 for the GTN 650.  Using the doublers pictured above I installed one behind the firewall but in front of the windscreen.  For that one I used the stock Garmin backing plate and didn't epoxy.  Mainly out of laziness, I didn't want to try to mess with that stuff crawled under the panel.  Interesting note I used a antenna I got off Ebay for my 172 that I never ended up using.  It's dirty looking but only cost maybe $40.


The last two I installed behind the cabin on the top of the tailcone.  I had to wait to talk to Bill at Airflow Systems to ensure this position wasn't going to interfere with the AC system I haven't fully installed yet.   It was easy to work with since the top skin isn't riveted down, just had to mark it and then match drill the holes, epoxy up and after cured clean the holes and bolt them on.



Magnetometer

I can't even pronounce what this is.  It's basically an electronic compass that needs to be clear of all sorts of things while limiting what's called the CAN bus down to 40 feet.  Stein did the harness and really the only place to put this is in the tailcone.  Also it needs to be level, within a few degrees of the plane heading and away from all sorts of things.  I saw all sorts of elaborate things hanging off the top of the tailcone but given that would be fairly close to my AC and lots of spinning metal I decided to make some type of shelve to span across the longerons.  That would ensure it's level in flight and hopefully give enough space to not run into interference.   I haven't tested this so the jury is still out.

What I did was make a tiny shelve across two aluminium angles to mount behind between the 2nd and 3rd compartments in the tail.  I do this I had to make part of it removable that I can rivet post testing.  I'll also epoxy it down to the longerons vs drilling holes to hold it in place.  Again going to do this after all the testing is done.


Short post for the amount of work that went into all this.  When it cools off a bit I'm going to go ahead and pull the plane to the driveway and start doing some testing and calibration... actually I'll probably get impatient and start messing with it.

Saturday, September 8, 2018

Happy 3rd Birthday! Hangar move punch list

Happy 3rd Birthday!

3 years and 1,115 hours into this project as of today! I hope to have the plane moved out of my garage and into the hangar within the next 6 months.  And then if all goes well, flying by this summer.  As exciting as that all is there is still quite a bit of heavy lifting before I get to that point.  I want to ensure I have as much done on the plane as possible before making the move.  I started to split my punch list into two categories; pre-hanger move and final assembly.

Hangar move punch list 

When it comes to the punch list there are some obvious items that can't be complete prior to the move.  For example I can't do the control rigging or wire up the landing lights until the wings are on.  I've used lists throughout the process to keep things straight, especially when working on items that don't have specific plans.  Here are all the current items I plan to have complete prior to moving.  Some are small few hour tasks, some are more in-depth and will require a bit more then a day or two to complete. In those cases I split them out into even more subtasks.   Here's what I'm looking at-

  • Wire ACS Starter switch
  • Wire Mag ½
  • Wire Cowl Flaps
  • Wire Door Sensors
  • 44-2- Bevel lower corners
    • 44-4 Install K1100-08 nutplates
  • Mount flaps Position sensor & run wire
  • Wire Headset Jacks
  • Wire USB Chargers
  • Control sticks
    • Install leather wrapping
    • Mount sticks
    • Wire Pilot/CoPilot – DB connectors
  • Mount Antennas
    • Comm #1 Comm #2
    • Nav #1 – Bob Archer Wingtip (Run cable)
    • G3X GPS – GA56 Tail
    • GTN 650 GPS – GA 35 Tail
    • G5 GPS – GA 56 Front
    • Transponder
  • Magnometer install
  • Engine Control Cables
  • Fabricate new Mix bracket.
  • Install Interior Nutplates
  • Refinish all plastic panels Interior
  • Air-condition
    • Mount evaporator to shelf
    • Crimp hose to fittings
    • Install return airflow
    • Install cabin flood and overhead duct
    • Wiring rotary switch
    • Wire Panel to Evaporator
  • Secure Aft FWD Skin and backing strip
  • Review and collect parts for final assembly
Posts without pictures aren't as fun so I decided to include a picture of my panel all powered up.  I took this a few days ago, however nothing is really going to function until I add the antennas and magnetometer.  I am slightly concerns though because when talking to Stein prior to ordering my antennas he mentioned that he's had problems with the transponders blowing a fuse or something when they're powered up without an antenna.  I really hope this isn't the case but to be safe moving forward I disabled all the avionic breakers in the VPX.




Wednesday, August 22, 2018

Firewall Forward Wiring

The Engine Information System (EIS) I'm installing as part of the G3X package is fairly robust. The Sensor Kit came with;

  • 6 Exhaust Gas Temp (EGT) probes
  • 6 Cylinder Head Temp (CHT) probes
  • Oil Temp probe
  • Mag Sensor (In lieu of a mechanical one)
  • Oil Pressure sensor
  • Manifold Pressure
  • Fuel Flow Transducer (Didn't realize this, had already bought one)
  • Shunt
I started this out by looking at the harness I received from Stein.  There are a lot of wires which actually just lines up with everything list above.  I spent a good bit of time upside down under the panel dressing the harness wires and routing them to my firewall passthroughs.  Given the length of the cables I needed to route the EGT and CHT wires for heads 2/4/6 on the pilot side, leaving heads 1/3/5 the copilot side, along with the rest of the wires.  I also went ahead and installed some non-EIS stuff such as wires for my ramair servo and air conditioning compressor.

With all parts installed and the harness wires sticking through I worked from the firewall moving forward.  I did sections at a time and used a mix of adel clamps and cable ties.  I tried to only use the adels in the firewall area but I decided to go ahead and use some heat stabilized ties which I can easily inspect each year.  It also gives a much cleaner look.








From an EIS perspective the only items I have to wire still are the sensor wires for the two shunts. Now I had previously decided to not use shunts and was going to rely on the VPX to give all power info.  For the most part I'm only concerned with if the Alternator is working and if the battery is charging and I've flown plenty of airplanes which a voltmeter was my only monitoring tool. However, because my harness had sensor wires for both primary and secondary alternators and because I hung a number of things independent of the VPX, I decided to go ahead and install two shunts.

The only reason I hadn't wired them yet is because it's suggested that you put 1 amp fused at the end of each wire so in the case there's a short, it doesn't blow out any of your avionics. I went back and forth on how to do this.  Originally was going to use 4 inline fuse holders with 1 amp blades, but that seems cumbersome.  Then I was thinking of doing a fusible link, which is basically a small wire encased in a fiberglass sheath.  This idea is if it gets too hot it melts and breaks the link. Then on a suggestion I looked at these really small micro fuses that I'll be able to solder in similar to a diode and shrink wrap it.  Should make it all safe and give it a clean look.

Wednesday, August 15, 2018

Airhorn!

What I've been telling people about the wiring progress is it's the little victories that make me happy.  One of those was tonight when I finally had a chance to wire up the Airhorn (Or is it 'air horn'). This device has been sitting on a shelve since I bought off Amazon a number of months ago. For $50 it's one of the cheapest components you can buy for your airplane.  I went with the Marco Tornado intended for Motorcycles, Cars & Trucks... so why not an airplane?

I originally was going to hang it off the VPX, but the larger 10 amps or more 'breakers' are at a premium. I decided to go ahead and hang it off the ANL feeding the VPX.  In fact going to use this same spot to connect my Air Conditioning Components and USB chargers.  I have breakers for the AC parts but for the rest I used in-line blade fuse holders.  I went with a 20A fuse to match the instructions and 14 gauge wire for all but the switch lead.

In normal operations I'm going to trigger this via the pinky button on the stick.  However I don't know if I'll have a tendency to hit it in flight so I went ahead and used the spare switch space I had for an Airhorn switch. If I find I don't need it and then end up needing a rocker switch for something else I can just remove it from the path later.


The airhorn is physically mounted in an open space on the firewall via one bolt.  It's a 5/16 hole, which like all the holes I have, get sealed up with some fire barrier stuff before placing in the hardware.  Wiring works off a relay and because it's built for car horns which rely on some voltage you need to jumper a smaller wire off the positive input over to another tab.  Then it works like any other switch where grounding it out triggers the relay and allows the larger amperage across.


With the help of my kids I decided to let my son flip the switches and my youngest daughter film.  Here's a video of the test, glad she didn't drop her phone!  Also pardon the mess of wires, it's still a work in progress.







Monday, July 30, 2018

Avionics Racking and Stacking & Power Distribution

Avionics Racking and Stacking


Over the last week I've been focused on getting all my avionics mounted either in the panel or behind the panel. Avionics and electrical for that matter dive into an entirely different set of skills and for me, uncharted waters per se. I can honestly say I've been planning my Avionics installation since before I ever began building as it's one of the things I am most excited about. I have several build log entries on my thoughts behind my layout. The most recent being specific to the panel design and electrical schematic.

The panel has changed very little since then although I did end up taking the TO/GA button off the panel and that will be placed on the stick. I found out I only needed a single button for AP disconnect and Control Wheel Steering (CWS).  The electrical on the other hand has changed quite a bit in terms of backup electrical and wire gauge, ect.  This document I'm changing as I move through the process, keeping it updated so I'll have an accurate representation of my system.  This will I assume be invaluable post build for maintenance purposes.

Jumping into it the first thing you really have to figure out is how and where you're going to place things behind the panel and attached to the sub-panel. I decided to start with the radio stack section because of the rack system I know where everything will go.  However the GTN650 is deeper than the 10 inches or so between the panel and the sub-panel so you have to cut a hole in the sub-panel to accommodate the extra depth.

To mark the hole to cut I removed the harness from the rack and put it on the panel insert which then I aligned it to the panel and tightened as much as I could.  Without the harness it almost fit all the way in there.  It allowed me to use a straight edge to mark out the area that will need to be removed.  Because of the wiring harness I went an extra inch to accommodate it on the left side.  Per the fuselage plans you also need to reinforce the cut out area and they give several options. One of which is to make a doubler out of .32 and the other uses angle pieces, but I had issues with that.  Using hand tools to make CNC level cuts is an skill I don't have, so instead of having a janky looking doubler I decided to instead go with the aluminium angle method.

I went with 1/8th angle over 1/16th angle.  It's a bit heavier but wanted to ensure this subpanel was reinforced and I don't know the stresses this area takes so better safe than sorry I assume.  I also had an piece of my old longeron that was removed from a previous mistake. This already had properly spaced holes drilled in it so using that saved me some time. I chose not to paint or prime it, but I did put a piece of rubber on the bottom to keep things in place.


With the sub-panel cut I decided to go ahead and mount in the panel piece and the G5.  Fun part is the G5 has a backup battery which allowed me to turn it on!  That makes it the first powered up avionics piece of equipment in N10JW.


I then moved the harness from my table to the inside of the plane.  Using the harness and spacing I was able to get a good visual representation of where I can locate equipment on the sub-panel. There's a lot of pieces that need to go back there and limited real estate available. I wanted to avoid placing anything behind the sub-panel for ease of maintenance.  So used some tape, snapped a pic and then posted on VAF to see what others had done.


Getting some solid feed back I decided to get building some mounts/rails for the GTR 20 (Comm#2), VPX and GTX 45R(Transponder/ADS-B).  I used a combination of various 1/16 aluminum angles picked up from Lowes and some scrap I had to fabricate these three items.  I also went ahead and screwed in the racks and placed the audio panel and 650 in.


The main issue with the GTX 45R is the depth, not only for placement but to be capable of removing it if need be later for service.  I decided to build a cradle out of angle and pull riveted it up to the panel and sub-panel.

GTX 45R cradle
After that I moved onto the GTR 20.  The idea is somewhat similiar to the cradle but instead of the uprights looking pieces I just put a few holes in the angle to mount the unit on top.  I tried different orientations of the piece but had to put it where it's at to avoid interference with my rudder trim and to still allow me to slide the GTX 45R out if need be.  Then just matched drilled some holes and pull riveted it on.

This is where I encountered my biggest challenge.  I could not for the life of me figure out a method to install the VPX and still allow access to the connectors while also not interfering with other connectors or the rudder trim cables.  I spent hours holding the VPX behind the panel trying to figure out what would work.  I then started thinking about way to mount it behind the sub-panel or putting large holes in the sub-panel to get it to work.

I really wanted to make it accessible and after fiddling around I determined I could put the VPX on a hinge, secure it to the sub-panel and then put another Lowe's special aluminum angle and attach it to the panel braces.  I originally tried to use my left over thumb quarter turn parts.  However the hole you have to drill for the receptacle really broke the diameter rule on the flange.  So I instead opted to use some additional angle to secure up the flange area and use a 1/4 bolt to attach.  Might be a tad overkill but better safe than sorry, don't want this thing falling off ever!  I have some 1/4" nutplates on order which I will install to make it a bit easier to unscrew later down the line. Here's a picture in the 'down' position.


Here is a picture of it in the 'up' position.  I chose this orientation because the Ethernet port is on the pilot side so it's easy to get to under the panel.  I was happy that it's secure, doesn't interfere with any of the panel pieces and allows me to get the rest of my panel pieces mounted in there without anymore spacing issues... or so I thought. (Edit: I thought the GSU (ADAHRS) mounted on the bottom of the panel, it's actually at the top and interferes with the way I mounted the VPX.  The solution is I'm mounting it on the brace to the left)


I ran into issues with both the GD40 (CO2 detector) and the GEA 24 (Engine monitoring).  Between the harness lead restrictions and the awkward shape of these I was having a hard time finding a place to put them that I was happy with.  After some thought I decided the best place for the GD40 is going to be on the backside of the center pedestal cover.  You have to remove these periodically for inspections so this is as easy as any place to get to it.  Not wanting to drill additional holes through the pieces however I decided to try and source a few Click Bond fasteners. These will allow me to attach the unit, and because it's not particularly heavy, it should work. (Edit: I realized later I didn't remove the carbon fiber under the insert.  Therefore I just used #6 countersunk screws and nylon lock washers)

That left me with the GEA which given the harness length really would only work somewhere to the right of the VPX, left of the radio stack.  I tried to make mount that I could attach to the subpanel and have it more or less hang out.  This is what I came up with...


It looked great but wasn't all that stable.  I pictured this thing rattling around causing all sorts of issues later on down the road.  I may have been able to extend the rails out and attach them between the panel and sub-panel for stability, but that would have required me to remove the fiberglass panel and probably mess up something doing so.

After removing it I messed around a bit with the harness and found I could put it under the GTR 20 and run it far enough on the other side of the sub-panel to make it a feasible mounting spot.  It's now nice and secure on the back side of the sub-panel essentially over the tunnel.  The four bolt pattern is visible in the below picture.  I put threaded side out on one of the bolts for a future adel mounting spot.  I also left the bracket end secured to the panel which will also function as a nice adel mounting spot if need be.




Power Distribution

In between working various equipment mounting tasks I tackled some of the main power distribution and grounding activities.  For power you run a #2 cable from the battery to the master contactor, to the starter contactor and then ultimately to the starter.  It's debatable on what is the best method for grounding an aluminium plane. The planes essentially locally ground everything to the frame, then you ground the engine to the engine mount which is grounded to the frame through the giant attachment bolts. My method is a more centralized approach and I'm grounding the starter to the engine mount, and then from there to the cabin where I have a massive tree of tabs for grounds (See picture above), and then a #2 back to the negative terminal of the battery.  This is probably over kill on grounding but I've flown several planes which have bad grounds somewhere resulting in audio feedback, intermittent lights or periodic failing antennas.

I previous ran conduits prior to securing the floor boards down.  My hope was that this would make running wires fairly painless.  This was not the case.... I don't know if it's the size of the conduit, the correlation or too many bends, but I tried the top two conduits to pull these large #2 gauge cables with no joy.  I decided to use the bottom one knowing it's a more straight shot and it finally worked out.  So in typical airplane build fashion the first one took an hour to do, the second about 4 mins.  I also went ahead and drilled the mid-fuse sections to accommodate the 3rd path for wires.  This allows me to still use the other two conduits as well as route wires from the wings to the panel area.


I have the battery side of things all terminated as well.  Leaving the power off obviously until I'm ready to start testing things.  Don't want to run into any issues or attempt a 'big bang' method of powering things up.

Wiring is reversed... had to remake cable.

Firewall forward I have the starter contactor and ANLs (giant fuses) installed.  These are for the alternator B-leads which are connected on the battery side of the starter contactor.  Additionally I'm route some #6 back into the cabin, into a separate ANL for the VPX.  The contactor side of that ANL will also feed my AC and Airhorn!


With equipment mounted and the possibility of everything having power I can push on to starting to connect things up.

Monday, July 23, 2018

Let there be light!

With all my new electrical supplies and tools, and the fact that I am home for at least 72 hours, I wanted to jump into something easy just to start building some knowledge and skills.  I decided working on the switches would be the best place to start... however after about 4 hours of messing with the switches I was stuck to a point that I decided to post on VAF about. Lesson learned- If you want to use a Vertical Power VPX system and also want a mix of dependent and independent lighting, then you need a dual power, single throw (DPST) switch. So had to order some of these and decided to move onto something else.

Back in May I did a quick post about my overhead lighting layout.  These two panel pieces had been sitting in a box so I figured why not get this all wired up instead.  Given that it's 105° Fahrenheit out I was also able to make this an inside activity for the most part.  It took a few hours but when I was done I had practiced some soldering, some heat shrinking, some molex pins and connectors and some wire routing.

With the panels completed I fished my harness down the center brace, connected some ziptie bases to hold the cables and then connected and screwed in the panels.  I really like how it turned out and I think this set up will work out well.


I've been using a 9 volt battery to test out light function.  At one point I was concerned because it looked like I had these wired in series because as I would turn additional lights on they would start to dim.  Being a bit paranoid I tested on the planes actual battery and the lights are extremely bright and no degradation as I turn them all on.  I'm actually going to hook these up to a rheostat as well so I can control the brightness, don't particularly like night flying and pretending on I'm a WW2 submarine. 

Just for some additional pictures I went ahead and connected 9 volt to take some additional pictures.  All these lights are independent for the most part.  I can have a single red or both on, or the two white lights, or the white lights and a red light, or all the lights on.  Here's what both Reds look like.


Here's what the two white lights look like. This is actually pretty dim, I think my 9 volt battery might be more like a 7 volt battery at this point.  The green push button also looks extremely bright, which it is, however once it's on ships power and I have the rheostat the red and white lights are about 10x brighter and the green light stays about the same.  So I will be able to turn the intensity down.


Tuesday, July 3, 2018

Christmas in July!

Today I received a surprise... well it wasn't really a surprise because I had been emailed the tracking numbers for the shipment.  However it was exciting nonetheless to received three large boxes from Steinair. These boxes contained all my avionics, wire harnesses, panel cutouts and other odds and ins that I purchased for my project.

I'm sort of at a loss of where to begin.  I've read all the usual books, watched a number of videos but still it's a bit overwhelming to look at all the stuff I now have sitting on two fold out tables.  I'll work on my organization just wanted to knock out the inventory and try to comprehend what I have and visualize where it goes.



Typically when I get a group of things I like to go ahead and start doing some progressive tasks to take the edge off.  It made sense to go ahead and match drill the holes and mark the area's of the carbon fiber panel that I'll need to drill. It's not much, but it's the first real progress I've made on the project in a month or so.