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My RV12 has finally moved on it's own wheels!  Still loads to do though, so here's a brief update.

First job after the fuselage-joining inspection was to prepare all of the undercarriage parts - the main legs, wheel fairing brackets, nose wheel fork etc.  Unfortunately I didn't take any pictures of the pre-installed parts!

Here's the first part installed - the left main undercarriage leg together with axle and fairing bracket.  Note to self:  Next time, put the brake caliper on BEFORE fitting the fairing bracket!   Installing and tightening the undercarriage bolts is a bit of a headache and I needed to drill a couple of holes in the belly skin, which are listed in an old service bulletin which weren't already present in my kit.  These holes are needed to get a 1/4" drive extension bar and socket onto the bolt heads.

Here's the right main leg with the brake caliper correctly installed.

Next it's time for the nose leg and fork to be fitted.  Although my kit came with an un-used standard fork, I've bought the up-rated nose fork as there have been many reports of the original design cracking.   The bolt with a stack of washers is where the tow bar attaches for ground handling.  The two black fixings at the top of the leg onto the firewall are 3/16" skin pins - being used as temporary fixings until the lower engine mount is bolted on to this location.  These holes will eventually be drilled out to 3/8".

The nose-wheel is free-castoring - there is no directly-coupled steering, so you change direction by use of rudder and differential brakes.

So onto the wheels.  I chose the paint the wheel halves as they'll be hidden inside fairings and open to corrosion if the aircraft eventually ends up living outside.  I used a Lazy Susan (used for cake decorating) to allow the wheels to be rotated when painting and this allowed for a decent finish.

I have no prior experience of assembling split-rim aircraft wheels with tubed tyres so it took a bit of reading the manual and fiddling to get the valve stem in the right place and not pinch the tubes, but finally they all went together OK.   What I also learnt was that I needed some new hex bits in sockets so I could correctly torque the bolts.

 So it's finally on it's wheels!

I just had to take the aircraft outside for it's first view of daylight! 

So moving on, I've continued with the electrical and avionics systems in readiness to fit the instrument panel.  This is needed before the canopy can be installed.

I completed the instrument panel itself by riveting stiffeners above each main screen cut-out, added some anchor nuts and drilled all of the circuit breaker holes.  Now it's primed and ready for the carbon-fibre film to be fitted.

More work proceeding on wiring.  Intercom, both PFDs (pilot and co-pilot main screens), autopilot, transponder and radio are now finished.  The main items to complete are the circuit breakers, switches and the engine interface unit (top left on the bulkhead).

A plan view of the part-completed avionics bay wiring.  Everything starts from the centre where the main aircraft harness comes up through the avionics bay shelf.

This is the Garmin GEA24 - the interface between the engine/airframe sensors and the EFIS screens.  Once the wiring is completed it'll be clipped to the bulkhead to allow the top cover to be installed without chafing. 

This is some of the electrical wiring in the engine bay - for the battery and start contactors, and the ammeter shunt.  The shunt is normally inside the Vans switch/fuse panel but I'm not using that.  Also in the picture are the manifold pressure sensor (top centre) and fuel pressure sensor on the right of the picture with the yellow cap on the pipe fitting. 

I've also temporarily installed the battery - merely to add some weight to the nose now the aircraft is on it's wheels.  Without this it wanted tip onto its tail! 

I took some time away from wiring to finish the braking system by installing the main leg brake pipes and attaching the rigid plastic pipes from the park-brake valve to the undercarriage brackets in the centre section.  I've chosen to use after-market braided flexible hoses on the legs instead of the Vans-specified aluminium pipes as this allows for removal of the brake calipers without needing to bend rigid pipes. 

Finally I completed the internal controls for the flaperons in readiness to trial-fit the wings.  With the wings installed, the flaperon control arms can be match-drilled whilst the controls are locked in a rigging position.  Hopefully I can get the aircraft out of the garage again in the next week and complete this step.

This view is looking down and aft on top of the flaperon controls - the white tubes exit the fuselage sides and engage with the flaperons on the trailing edge of the wings.  The green rods connect to the mixer between the seats which in turn connects to the pilots' control sticks.

I wasn't happy that the two bolts on the end of the green push-rods were in alignment when the controls were in neutral so took the lot out and re-measured/adjusted the rod ends until everything was aligned accurately.  It's difficult to get the price dimension stated in the build manual and surprising how a quarter turn either way on opposite rods can have a dramatic effect.

I'm not proceeding as quick as expected but hopefully will complete the electrics/avionics in the next couple of weeks and start on the canopy.

Fuselage structure completed.

We've been away on holiday and I managed to crack a couple of ribs in my back falling off some steps whilst gardening, but nevertheless good progress made since my last blog entry.  More wiring completed, flying controls almost finished and significantly, the two halves of the fuselage have been joined together!

I've finished routing the fuselage wiring loom and pitot-static pipes to the instrument panel. This is looking forwards/upwards in the centre console.  They go behind and over the rudder pedal assembly which is really awkward, as is installing the small cable guide to the left of the central rudder bar pivot.  Anyway it's all in and ready for terminating at the panel.

I've also installed the control sticks and associated flaperon push-rods (just visible below the white horizontal tube) and the rudder and elevator cables.  I mis-rigged the control stick push-rods initially (mis-read 9 5/16" on my steel rule and set the distance as 9 5/32" instead) which meant the control sticks weren't parallel with the controls in a neutral position. Therefore  I had to strip the sticks and push-rods out and do it again - a real pain as there are spacing washers needed which I ended up super-gluing in place.

The transmit switch wiring is now in.  Not visible are the cycle handlebar grips at the top of the control sticks which also contain the Press-to-transmit (PTT) switches.  Now I can remove the reminder label! 

I've completed all of the headset wiring - this picture just shows the co-pilot's sockets including a stereo jack.  Deborah (SWMBO) doesn't find flying very rewarding, so she can independently listen to an iBook or music whist I manage the radio and get us to somewhere of interest!  It does mean I have to have a separate PS Engineering PM3000)  intercom system which is another deviation from the Vans plans.

I've also added supplementary BOSE headset connectors which allow the use of aircraft-powered ANR headsets instead of using battery packs.  All of this took well over a day to do both seats, whereas using the Van's harness, it could probably have been done in a couple of hours!  Nevertheless I don't have any of the awkward miniature Molex plugs that Vans use and I have additional capabilities.

The last bit of fuselage wiring so far was to terminate the spar pin switches.  These switches are there to warn the pilot if the wing-spar pins aren't secure and prevent the engine being started. My kit came with magnetic reed switches which are meant to be awkward to adjust. Subsequently Vans came out with an upgrade for use with miniature push-button switches (mounted just below the 2 shiny screws) so I've gone with the later system.

This shows the left wing disconnect panel complete with AOA pipe.  I've temporarily fitted the plate so I can mask around the outside ready to prime the skin beneath.  The piece of foam taped to the skin is protecting the Garmin outside-air-temperature probe which can easily be damaged but needs to be fitted now as this can only be accessed through the wing break cover plate.

Now it's finally time to do some serious structural work and join the front and rear sections of the fuselage together.  With some assistance I got the tail cone down from where it's been hanging from the ceiling for the last 20 months and positioned it onto the rolling trolley.

The forward fuselage is still on it's side as I was completing some flying control work.   With the tail cone on the trolley I can move it around single-handed to get the two parts aligned.

I took the opportunity to install the magnetometer and wiring harness into the tail cone and complete the re-worked static pipe system before the two halves were joined - much easier access than doing it lying down though the fuselage under the roll bar.  I also added a disconnect plug for all of the tail cone wiring (magnetometer and pitch trim) and also for the nav antenna so I can just plug the two parts together when the mechanical work is complete.

So on to the fuselage assembly.  Here's a view from the left side of the front and rear fuselage sections cleco'd together and ready to rivet.  Not really visible but also in place are the seat belt shoulder strap fittings either side of the roll-bar brace.

And a view from below.  Setting all of the rivets probably took about a day which includes two lower fuselage panels below the baggage bay which have the exit holes for the flaperon controls.

Main riveting complete and ready for the turtle-deck panels (around the back window) to be installed.

A view looking down gives an idea of the length of the fuselage which now takes up almost the whole depth of the garage.  There will be just enough room to get the engine installed but not the fin/rudder or propeller.

Of course something had to go slightly amiss during the joining process and it's shown here - the top skin should sit over the lower skin.  I didn't notice the error as I pulled the two halves together and it didn't help that I did all of the joining on my own.  Fortunately I spotted it before the turtle-deck panels were installed.  It only meant drilling out 10 rivets and then flexing the skins apart carefully to to get them in the right place. Unfortunately I'd made the same mistake on both left and right sides of the fuselage!

Next job is to install the turtle-deck panels and prepare the rear window.  Here the panels are in place and cleco'd with the perspex window ( a flat sheet which has to be bent to the right shape in situ).  I was very nervous doing this in case I damaged the window but so far so good.  The forward window fixing holes are then match-drilled into the roll bar and then with the window removed, the roll-bar holes are opened-up to final-size and tapped with 6-32 UNC threads for the securing screws.    The window won't finally be installed for a while - access is needed to finish the fuel tank installation and I have to complete painting the roll bar.  I want to leave the painting until the canopy installation is done as that may produce some scratches etc.

Turtle-deck lower and rear edges riveted in place.

Finally with the rear window removed and the fuselage positioned onto both lower trestles where it will live until the avionics are complete and the engine cowlings and landing gear are installed over the next few weeks. Before all of that it's inspection time again.

A bit more progress

I've done a bit more wiring (the main harness is now all installed in the fuselage) and I've also started on the flying controls.

 This is the autopilot roll servo installed at the back of the centre fuselage with wiring completed.  If the tail cone was fitted I'd have to do this lying down inside the fuselage at arms length!   I'm adding tail-cone disconnects for the magnetometer, trim motor and Nav antenna so I can just plug them all together when the two part of the structure are jointed together.

 The two connectors on the left are for the attitude/air data computer which hangs on the underside of the baggage bay floor panel.  It will also have 3 plastic pipes (pitot, static and AOA).

Here's the autopilot roll servo below the pilot's seat - we're looking down and the front of the aircraft is to the left. Note to self - fit the connecting rod bolt into the operating arm before fitting the servo next time!

Roll servo viewed looking left across the cockpit.  The troublesome bolt is now visible and wrapped in tape to keep it in place!

The two avionic cooling fans have gone in.  They only use two fixing screws and the instructions say not to over-tighten or the flanges will break.  So I made some spacers from spare brake pipe.

The rats-nest of wiring in the foot-well is growing but I won't deal with this for a while - I'm more bothered about items in the centre fuselage and rearwards so that I can finish these with easy access and get the tail cone attached.

So starting to deal with the controls now that all of the wiring is in the centre tunnel.  First job - paint then install the flap operating arm and mixer assembly. Getting the mixer to clear the wiring bundle was a real headache!

Another view of the flaperon mixer.  You can see the protective cover at the top over the wiring harness - there's just no room left for any extra wiring.   

The flap handle mounting at the rear of the control tunnel (the two lugs are for the seat belts).  Another tight squeeze so the flap handle cross-tube doesn't rub on the fuel pipe (right side) or wire harness on the left.  At least by installing the avionics wing before the controls, I won't have to disturb this or try and feed cables in with the controls attached which I think would be impossible.

The RV12 is designed to met the LSA standard with a maximum weight including fuel and passengers of just 600Kg.  So everything has to be light.  This picture to me seems to take it to the extreme.  At the top is one of the control rods that join the control column to the flaperon mixer for roll control.  It's not much thicker than a pencil!  At the bottom is one of the push-pull rods that goes rear to the flaperon operating arms.

Finally for this week a bit more wiring.  I completed the wing root connections - designed to enable the wings to be quickly removed for transport just like a glider.   Above is the right wing connector

This is the left wing connector complete with a pneumatic pipe disconnect for the AOA (angle of attack) sensor.  I've now just got to terminate the headset sockets and add a BOSE powered socket and then I can close the wing root panels.

Woodwork and wiring

A short update - no major changes visible just yet.

I decided to make some trestles as they're needed for future maintenance and also when I join the fuselage and tail-cone in a few weeks.  I'm short of bench space with the fuselage on it so now seems an opportune time.  Vans provide some height and width recommendations so I've followed their instructions.

Here are the completed trestles - just waiting for two layers of carpet to be added on top as padding to protect the fuselage.

Here the trestles are on a trolley so I can move the aircraft around on my own.  The fuselage is on it's side again for access to paint the interior.

 

I've masked off large areas as I'm only painting the areas that will be visible when the interior is fitted.   I still have to paint the roll bar and cockpit side rails where the canopy fits but am leaving that for a while as it'll get marked during the build.

 Another view of the painted interior.  The fuselage is very stable so no worries about it falling off the trestles!

Next stage is to start wiring!   As mentioned in the previous post, I'm deviating from the plans and doing my own thing with point-to point wiring and not using the Vans-supplied junction box or fuse/switch panel.  I have stripped the Vans fuselage and options harnesses to use the coloured wiring where possible - at least this way the wire functions will still correspond to the factory drawings.  I will eventually produce an accurate wiring diagram but for now am using a combination of Vans and Garmin drawings and my own ideas.

This is the Vans complete drawing for a G3X-equipped RV12.  I had it printed full size (A0) by a local print shop but it's still not really large enough to use even with a magnifying glass!.  I still need to use the laptop so I can zoom in the read wire colours or plug numbers. The big bit in the centre is the junction box that I'm discarding.

So underway.  Here is the conduit on the back of the spar box and some of the wiring is starting to go in including power to the fuel pump.

Looking down on the centre tunnel between the seats with most of the cockpit electrical wiring (lights, spar switches, canopy latch, fuel pump etc) in place although not tidied or clipped.  Also in there are pitot and static pipes and antenna cables.  I still have to add avionic wiring for the G3X EFIS and autopilot.  It's going to get extremely tight to get all of the required wires through the bulkhead bushes! 

Spaghetti starting to build up.  I will start by completing the pre-terminated lighting wires at the wing break plugs and then work inwards clipping as I go so I don't cut any of the Vans cables too short.  However, by doing this it's essential to make sure all required wires are in place first. I'm adding a few extras such as power for ANR headsets (and additional BOSE connectors) plus audio to a remote GoPro camera so it will record the intercom and radio as well as the image.

Here is the left wing-root waiting for the wiring to be terminated and the plug mounted.  I'm adding the optional AOA sensor so there's an additional pipe to connect to the wing as well.

As avionics has always been my day job, I'm using standard wiring techniques including sleeving on exposed wiring to prevent chafing.  It also tidies things up and makes it look better!

More of the same next time plus hopefully some of the flying controls.