Wednesday, June 28, 2023

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

Thursday, June 15, 2023

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

Wednesday, June 14, 2023

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

Monday, June 12, 2023

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

Monday, June 5, 2023

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