Pitot-Static and AOA lines, Fuel lines, Turtedeck Clips, Priming

After taking a week off from the project for vacation time, we got back to work on the airplane.

We fixed the blue tubing that was inadvertently damaged when opening/closing the wing.  This tubing was for our angle-of-attack (AOA) sensor.  The bad section was cut out, and the tubing ends were then spliced together with a coupler fitting.  Once repaired, the Pitot tubing (green) and AOA tubing (blue) were run from the wing to the Garmin GSU25 (which is attached to the back of the G3). A static line (clear tubing) was also run from the GSU25 to a spot behind the panel.  The Pitot and static tubes have Teed connections that run to our backup instrument, the Garmin G5.

Pitot, AOA, and Static lines installed

We riveted on a couple of small clips to the turtledeck.  This should help keep the turtledeck secured in the center since the spacing between quarter turn fasteners was a bit long.

Clips added to the turtledeck.

On the passenger side, a few new fuel hoses were made.  The upper one is for a vent line to the tank, and the lower line is the fuel outlet port. The vent line was tricky as it had to be routed under the root rib to avoid being pinched when opening and closing the wing.  We found that a 150 degree hose end allowed the hose to be routed nicely back on itself.  Protective Tessa tape was applied around the hose to give it some extra protection where it runs under the root web.  A secondary protective sleeve was also applied around part of the fuel and vent lines to prevent any chafing when opening and closing the wing.

Vent (left) and fuel line (right) connected

A few parts were primed, including two fairings (used where the wing and windscreen meet), and the Com antenna base.  A few pinholes were found in the fairings, which is pretty typical for fiberglass parts.  These were fixed, sanded, and another coat of primer applied.  Hours: 14

3 primed parts

Glare shield, Fuel lines, W&B check

Another fuel hose connection was completed, and we now have a shut-off valve between the left wing and header tank.  This shut-off valve can be closed to prevent fuel from cross-feeding between the wings if parked on a slope.                                     

Fuel hose from right tank to shut-off valve

A flat black vinyl covering was applied to the glare shield, and two small GPS antennas (backups for the G3x and G5) were installed on top.   A test fit of the glare shield was done and we're happy with how it looks.  Final installation of the glare-shield will wait until we finish some other work behind the panel (pitot-static routing and wiring cleanup).  We also removed a protective film covering from the windshield so we can finally see out the front windshield!

Flat black glare shield in place

Next we did a quick check of the weight and balance to see where we stand now.  The plane is a bit heavier than average, which was expected to some degree because of our choice of engine and nose-gear, plus the added auto-pilot.  Right now, the empty plane weighs 808.6 lbs and it will gain a few more pounds before completion. The empty CG is currently about 10.8 inches aft of the datum, which falls nicely in the target range (9" to 15.5" inches).  A quick check with added passengers and fuel indicates that we are in decent shape, but we'll do more exact calculations once everything is complete.  Hours: 4.5

Flap gap seals, Fuel lines

Now that the flaps are finally installed, we decided to install the flap gap seals, which are aluminum strips that span the gap between the wing and the flaps.  We had previously primed and painted these pieces, so all we had to do was rivet them to the wings.

Flap gap seals installed

More time was spent planning out the fuel lines from the wings to the header tank. The wings were folded several times during this process as we need to ensure that the hose routing and hose lengths will accommodate folding of the wings.  Hose ends were attached to complete two of the hoses that run to the header tank.  We are waiting on parts to finish the remaining hoses.

Right angle connectors installed on upper hoses

Additionally, work has started on installation of the rear baggage panels.  We found that a few attachment holes that were drilled into these panels no longer line up with the holes in the chassis tabs.  This may have been due to flexing of the tubes that occurred when shrinking the fuselage fabric.  We may just remake that panel as we have some spare aluminum sheet.

Work is also underway on installation of the glare-shield.  Some right angle brackets were made to help support the glare-shield along the front edge.   Hours: 9

Fairings, Wing wiring, Flap hinges, AOA tubing, Seatbelts, Fuel lines, Door latches

 A couple of fiberglass fairings were trimmed to fit.  These fairings connect the butt rib to the windshield and clean up the area there.  Attachment holes were drilled in the fairing and the windshield using a drill bit for plastic.  After trimming, pinholes in the fiberglass pieces were filled with dry-micro.

Fitting of fiberglass root-wing fairings

The navigation and beacon lights were installed in the wing tips and wired up to the switches in the panel.  A minor mistake was made by wiring up the green light to the pilot side wing, but quickly found this during test and swapped the lights so they were correct.  

Michael labeling wires for the Nav. lights

Previously we mentioned that the flaps had too much friction, so we reamed out the bushing holes slightly, and also found some paint overspray in wing holes that we reamed out.  After this work, the flaps now function nicely.

Flap hinge works great now

The door latches were painted a flat black (using plasti-dip paint) and one of them (previously drilled) was attached to the door.  The strut-attach brackets were also painted.

Door latch painted flat black and attached

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Strut attach brackets

We ran into an issue with the tubing for the AOA line (which is run adjacent to the pitot line).  While working on the routing of these tubes along with the fuel lines from the wings, the blue AOA line got pinched when attempting to fold the wings, which tore a nice hole in the tubing.  We will repair this and adjust the routing to prevent this from happening again.  

Blue AOA tubing with a tear

Seatbelts were installed and and all seatbelts torqued down.

Michael installing seat belts

We opened up the rear slot in tje butt-rib (using a dremel tool with sanding bit) to allow for the fuel fittings to rotate into position when the wings are folded/unfolded.  Hours: 28

Fuel line for right wing

Ed checking fuel line routing while closing wing

Plane relocation, plus work on flaps, wiring, fairings

 In prep for moving our plane to Sanford (TTA), we completed fabrication of travel struts.  Two rear struts had previously been made, but we made a couple of front struts that attach from a landing gear mount to the spar tube.  This adds some support when the wings are folded and make it safer for travel.  

Front travel strut attached

We actually unfolded the wings to load the plane on the trailer as this keeps the center of gravity forward of the main gear.  Once the plane was on the trailer and the front tied down, we folded the wings back and installed the travel struts.  We then finished tying it down and successfully transported it to Sanford.  This was a big accomplishment as this is the first time we trailered it with wings folded.  This is the airport where we will be performing our initial test flights.

Removing travel struts after towing

Wing unfolding

Plane at new home

Some other work we did on the airplane is listed below: 

A thin plastic corrugated tube was inserted through the front spar of each wing for use as a protective conduit for wiring.  Wires were routed through these tubes in prep for wiring up the wingtip lights.

The flap pulleys were installed and torqued down.  The flab cables were fabricated and installed.  We ran into a problem on the right wing as the flap wire had inadvertently wrapped around the aileron cable, which probably happened sometime during the paint process.  This was easy to fix as we just removed one pulley and had enough room to fish the wire back where it was supposed to go.

The flaps were tested and we found that there is too much friction in the system, as the flap spring couldn't always pull the flaps all the way back up when retracted.  After further investigation, we found that some of the bushings are not rotating freely, so we will need to ream out the holes just a tiny bit more to enable these to work correctly. 

An aluminum fairing was made to cover the gap between the fuselage and butt rib.  Holes were drilled and clecos installed.  This will be painted before final installation.

Some work was started on some fiberglass fairings that cover the area between the butt ribswing and windshield.  The right fairing was trimmed a bit, but more work still needs to be done on this.  Hours: 30

Travel Struts, Folding Wings, Trim Connector

Now that we have complete wings that are attached, we found a problem when we went to fold the wings.  There was some interference with the back of the root rib.  This was fixed by trimming the edge of the butt ribs and also trimming a little bit of the plexiglass sunroof.  The wings fold very nicely now.

Butt rib and plexi trimmed

Wings folded after interference fixed

Two rear travel struts were fabricated.  When the wings are folded, these struts pin the wings to the tail to prevent them from moving while towing.  Work has aslo begun on two additional front travel struts.  Brackets were made from angle steel that will attach to landing gear bolts and will be the lower attach point for those struts.

Rear travel struts (gray)

A 4-wire connector, located at the bottom of the tail, was installed on the power and control wires for the trim motor. It was secured with cable ties, which was not a trivial task due to the limited access.  Function was tested and the trim motor moves as expected when the trim buttons are pressed. 

Hours: 18

N-Numbers, Aileron cables Regulator heatsink

We finally put our N-number (N371EM) on the airplane.  These were vinyl letters that are the same color as the green stripe.  We also added the Just Aircraft logo to the tail, which was a decal supplied by the factory

Michael adding N-Number and Just logo on right side

Ed adding N-number to left side

Tail with N-number and "Just" logo

After waiting a few months, we finally received a new (optional) heatsink kit for our Rotax voltage regulators which we installed.  Several builders have issues with high temperatures from these regulators which can cause damage to the regulator connectors, and this retrofit (approved and sold by Rotax) helps with this issue.  We expect that this will solve any issues, but we also have the option of ducting cool air to the regulators if early testing indicates they are getting too warm.

New heatsink attached to voltage regulator

We assembled the aileron cables, using nicopress sleeves and thimbles at the attachment points.  A turnbuckle was installed on both the right and left cables behind the seats.  This is where the cables running from the wings attach to the cables running to the controls.

Turnbuckle connection for the ailerons

We also installed a turnbuckle for the aileron pass-thru cable that attaches the two down-aileron cables from each wing.  Hours: 15

Aileron pass-thru cable with turnbuckle

Turtledeck slots, Green striping

Slots were carefully cut into both sides of the the turtledeck at the location where the aileron and flap cables exit the fuselage.   The slot was cut thin at first, and then widened as needed after several trial fittings until we had decent clearance on all sides of the cables.

Slot cut into turtledeck

Cables passing through slot in turtledeck

More green vinyl striping was added, this tie along the side kick panels and the rudder.  Also, some anti-chafe tape was added to a few locations where panels overlap to prevent abrading the paint.  Hours: 3

Green stripe added to side kick panels

Green stripe on tail

Aileron, ELT, Pitot, Jury Struts, and Turtledeck

Michael installed the green vinyl strips on on the wings.  This allowed us to then install both of the ailerons.  Once that was done the control cables were re-attached at each of the control horns on the flaps and ailerons.

We had to obtain a new battery for our ELT since the original had exceeded it's expiration date.  A new battery was obtained and the ELT was re-installed into its cradle in the tail of the airplane.

New ELT Battery

Ed started working on the turtledeck modifications that are needed to allow the control cables to enter the cabin area.  A lot of precise measurements needed to be made before determining the location of the holes.

The pitot/AOA probe was installed onto its mounting stalk.  This required cutting down and deburring the probe tubes and trimming the hoses to the required length before connecting with air-tight push-on connectors.  The green hose is for pitot ram air and the blue hose is for the AOA probe.

Connecting the pitot/AOA probe

Pitot/AOA probe installed

The jury strut to main strut attach brackets needed to drilled and painted.  Once that was complete the jury struts were installed.  Michael tried various ways to  install the jury struts but found that installing them on the main strut first and then attaching them to the wing was the easiest method.  The jury struts were moved around until the main strut was straight (i.e. no bowing up or down) and then the bolts were torqued to their final value.

Left side jury strut installed

Right side jury strut installed

Starting to look like an airplane!

Hours: 8

Flaps, elevators, and jury strut

We brought more parts to the airport, and started working on various things.  The window on one door was trimmed a bit in one corner to eliminate some interference.  Green striping tape was installed on most of the control surfaces where the orange paint borders white paint.  We still need to apply the tape to the cowl and rudder.  The flaps were installed on the wings which was a nice accomplishment.

Flap installed on right wing (no aileron yet)

Michael spent a bit of time adjusting the jury struts and their brackets.  The brackets didn't fit our lift strut very well, so took some bending and persuading to fit better.  These brackets were then removed so that they could be painted white.

Michael working on the lift struts

The elevators were attached to the tail.  The two elevators are bolted together inside the tail, and are installed on their hinges with clevis pins that are held in place with cotter pins.  It felt good to get another control surface attached to the plane.  Hours: 20

Ed installing a cotter pin for the elevators

Wings attached!

We achieved another milestone by getting both wings attached to the airplane.  Rain was pouring down when we were about to hang the second wing.  We had to wait until the rain let up because the rain pelting the metal roof created so much noise that we couldn't hear each other speak.  But in the end we got both wings installed successfully. 

Wings installed.  Happy Builders.

We then installed an aluminum cap strip across the gap between the windshield and sunroof.  We had attached some thin neoprene gasket to the underside of the strip before installing to help keep it weather tight.

Next, we adjusted the newly vented fuel caps so that they fit snugly in the tanks, and inserted them into the empty fuel ports at the top of each wing.  Hours: 8

Vented fuel caps inserted

Tank cleanout, Windscreen work, Stripe, Fuel cap

To clean out the fiberglass fuel tanks and also ensure there is no uncured resin, we used the clean-out method recommended by the factory.  Basically,  add 1 gallon of lacquer thinner to the tank (ensuring all openings are sealed), swish around in the wing while turning and tilting it to ensure all surfaces of the tank get wet (about 30-40 seconds), then remove cap to release pressure as it builds quickly.  Drain and repeat with 2nd gallon.  Drained fluid should be clearer.  Drain and repeat with 3rd gallon.  This 3rd gallon comes out clear, so it is saved for use on the 2nd wing.  This process was then repeated on the 2nd wing.  A total of 5 gallons of lacquer thinner was required using this method. 

Michael sealing fuel port in prep for fuel tank cleanout

During a final test fit of the windshield, we found that some of the attachment screws could catch the sides of the holes in the windscreen.  Since this could lead to eventual cracking of the windshield, we carefully enlargened the holes for better clearance by using a Dremel tool with a cylindrical bit.

A few holes in plastic windscreen enlargened

A green stripe (3M light green material) was applied to the side of the fuselage between the white and orange paint.  We like the look and plan on adding this stripe material to the wings, cowl, and control surfaces that have both orange and white.

Green stripe added to sides of fuselage

The fuel caps need to be vented, so we disassembled the fuel cap and drilled a 3/16" hole in the top and bottom sections of each fuel cap.  We then upsized the hole to 1/4" in the upper fuel cap, but only to half the depth.  The fuel vent tubes were cleaned and epoxied into the 1/4 inch holes.

Hole drilled in top of fuel cap

Vent tubes epoxied into the fuel caps

We decided to spray black Plasti-dip on the seat position latch handles.  After masking off most of the base, the T-handles were sprayed with about 6 coats.  Hours: 13

Plasti-dip on seat position latch handles