Airworthiness Cert, Vortex Generators, Rigging Check, High speed taxi test

We finally received our airworthiness certificate on Aug 20, but had some work to do before first flight.  During our trip to Brasstown for transition training, our flight instructor (Vic) at Plane Fun Aircraft gave us many tips, and strongly recommended that we add vortex generators (VGs) before first flight.  These should lower stall speed a bit and they reportedly do not affect top speed.  We originally planned on adding them post flight to gauge their effectiveness, but changed our minds after talking to him.

The VGs that came with our kit had sharp corners and no adhesive (they recommended a form of super glue).  We elected to order some new ones (Stolspeed VGs) as these had a more rounded shape and came with 3M adhesive that is removable.  We installed them per instructions.  The VGs at the wing tips are installed with a closer spacing to ensure the wing tips stall after the root wing stalls.  We also installed VGs on the bottom of the horizontal stabilizers.

VGs on the wing

VGs on horizontal stabilizer

Also, even though our wings were rigged at the factory, we were advised to double check this   According to Vic, If the wing is leveled at the root, and measures something like -1 or -1.5 degree angle at the center (angle of incidence), then it should be about -2 to -3 degrees at the wing tip.  Having a little twist like helps ensure that the wing tips will stall after the main wing stalls. More important is to ensure that both wings are identical.  When we measured our wings, we found that the right wing was close to level across the whole span (no twist).  The left wing was a little better but had just -0.8 degrees at the tip.  We adjusted the right wing as far as allowed by loosening the jury strut and then rotating the main strut's clevis fork rod end, and were able to get it to -1.2 degrees at the tip (with about 0.6 degrees center).  The left wing was then adjusted to match this. 

We also ran another taxi test.  This time it was a higher speed taxi test down the runway.  Power was applied gradually while holding back the stick until the nose lifted off the ground, then reduced to hold the position.   The test went well, although we noted that the airspeed on our Garmin G3x never dropped under 23 MPH.  We contacted Garmin and found that this means we need to have our GSU25c (ADAHRS) replaced.  Luckily, this will be covered under warranty.  

We are also finding that our coolant temps still run a little high during taxi on hot days so we may need to adjust the cowling opening and/or radiator position sometime in the future to improve this.

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

Orange Paint, Horiz Stabilizer, Boot Cowl, Windscreen, Gear Leg covers

We painted some more parts Ocala orange in our paint booth, including two side fuselage foot-well panels, 1 inspection cover, and 2 aluminum gear leg covers.

Orange paint sprayed on 5 parts

The horizontal stabilizers were inserted into horizontal tubes in the tail and bolted in place.  The flying wires for the horiz. stabilizers were also installed and all bolts torqued as required.

Installing a horiz. stabilizer

Flying wires attached

The boot cowl was installed, and the windshield was set in place.  Next screws were installed along the front through the boot cowl and holds the lower edge of the windshield in place.

Boot cowl installed; Line of screws along bottom of windscreen

We attached the (orange) gear leg covers on the bottom of the fuselage.   

Attaching gear leg covers

Right gear leg cover. Finish is nice and shiny.

The front and rear windshield brackets were installed with stainless rivets. 

Rear windshield bracket installed (with "Experimental" lettering)

Finally, we temporarily attached the footwell panels so that we could see how the overall paint scheme looks and make sure everything lines up right. Here is a nice shot of the airplane with the cowling and panels in place.  We still have some blue protective tape on some parts, and are likely adding a stripe at the border between the orange and white.  Very happy with how it's looking so far.  Hours: 21

Nice side shot of airplane with painted parts in place

Misc Work on Various Parts

 In order to set the brake/rudder pedal position, the rudder was re-installed on the vertical stabilizer.  3/16" holes were drilled in the horn to allow the rudder cables to be attached using shackles.  The Rudder hard stops were adjusted with a grinder to allow +\-30 degrees of motion.  Attention was then moved to the rudder pedals.  A turnbuckle was attached to the two outside rudder pedals.  With the rudder pedals 6" from the firewall the correct rudder cable length was determined and the cable was cut to the length and a thimble was swagged.  The plans didn't call for rudder return springs, but we added two springs to the rudder pedals that attaches near the firewall for this function.

Rudder Pedals with Turnbuckle and Return Springs

The elevator trim tab and trim servo were installed on the elevator.  The trim servo was connected to the imbedded wire we installed earlier in the elevator. 

Trim Tab and Servo installed

A cover for the trim servo was designed quite awhile ago.  The part was 3D printed but needed to be finished quite a bit.  The 3D part was sanded and then epoxy filler was added to the surface.  After a lot of sanding the part was primed.  After the primer dried, the part was painted to match the elevator with a coat of Vestal White paint.

(top) original 3D Printed, (bottom) Primed Part

Painted Trim Server Cover

We're still trying to find the perfect part for the brake lines that go from the Grove gear to the brake calipers.  We've settled on a 10" hose with 90 Degree fitting on one end and straight fitting on the other.  Parts have been ordered and we are waiting on delivery.

A lot of time has been spent on the FreeCAD designing the panel.  Still waffling on using either Klixon CB or Blade style fuses.  Each has its merits.  Currently leaning toward using the Klixon CBs.

Hours: 20

Fuselage covering work

Installed ten protective fabric doilies on the tail at various locations such as the attachment points for the flying wires and the horizontal stabilizer.

One of the tail doilies installed

Also installed protective doilies around the nose wheel bracket attach points, plus a few alternate main gear attach points that would be used if the plane is ever converted to a tail-wheel.  Also installed a grommet and doily for the header tank drain opening in the bottom of the fuselage.

Two doiles at nose wheel bracket attach points

We spent a bit of time determining exactly where to place the gascolator, as we want to ensure it's placed at the lowest point along the fuel run, and want to keep the fuel-line routing as clean as possible.  The location we chose is beneath the passenger seats.  A grommet and doily were installed in the fabric at the location where the gascolator drain will protrude out the bottom of the fuselage.

Gascolator installed, with hole in fuselage beneath it

Ten additional tiny patches/doilies were also placed on the fabric at the landing gear attach brackets locations (inside surface of fabric).  These were mainly placed there to plug up some small air gaps that still existed around those brackets.

Small patches added at gear attach points to prevent air filtration

We installed plastic fairings and doilies at the points where the rudder cables exit the fuselage.  Although we spent a lot of time lining these up to get it right the first time, we didn't.  We tested it out by installing the rudder and cables (temporarily), and then watched the cables on both sides as the rudder was moved to the left and right.  The cables and fairings worked great for "most" of the rudder travel, but we had a problem at the full left and right positions because the cables were rubbing the fairings slightly.   We didn't want any interference, so decided to remove the fairings and do it over again.  Before we removed the fairings, we installed patches on the inside over those locations just to ensure that the fabric would not stretch and mess up the fabric on the right or left sides.  We then removed the fairings, cleaned up the glue, and reinstalled the plastic fairings.   Still need to add doilies over these.   Hours: 15

Rudder cable fairing installed

Landing gear opening, baggage opening, tail access plate

Haven't taken the opportunity to append the blog for a while, so here is a consolidated update.

We ironed the fabric for the landing gear opening to tighten up the fabric that was previously glued down.  We then created several unique doilies for the openings in the fabric for the many protrusions that pop through the fabric in the landing gear area., then glued them down. Also applied a fabric finishing tape to one of the seams.

We found a few additional small unpainted spots on the fuselage that had a bit of rust, so cleaned them up, then applied epoxy paint to protect the areas.

Holes were drilled to accommodate the bottom access plate for the tail.

Lastly, two small brackets were made for the latches that will keep the baggage door closed.  The lower bracket slipped while drilling the second hole which messed up the alignment, so we decided to  fix this by shifting the bracket down a bit and redrilling.

Hours: 8

Top view of fabric around the landing gear

Holes drilled for baggage door bracket.

Rudder Perimeter Tapes

We are now working on the the perimeter tapes on the the rudder.  We marked the location and added three coats of U500 adhesive.  Once dried, we attached the chord-wise perimeter tapes.  Hours: 2

Elevators Covered, Starting Rudder

We can now say the elevators are covered.  Another tick mark on the todo list is done.  We've now covered 5 parts.  Next up is the rudder.  We put 3 coats of adhesive on the outer perimeter tubes and cut the fabric to rough shape.  Hours 2.5

Ed with his covered Elevator

Mike with his covered Elevator

Elevator Fabric Work

We continued our fabric work on the Elevators.  We are working on the perimeter tapes on the sides and trailing edge of the parts.  Hours: 1.0

Trim Tab and Elevator Covering

Trim Tab work applying two perimeter tapes.  Also more elevator work putting on finishing tapes and starting the perimeter tapes.  Hours: 3

More Elevator Covering

Simple entry......We applied more U500 adhesive and finishing tapes.  Hours 2.0

Two Elevators in process

More Elevator Covering

Continued our work on the two elevators.  The pre-shrunk lightweight fabric was removed from the frame.  Two fabric gussets were made from this material.  One for the trim servo mounting fabric plate and the other to cover a plastic grommet where the trim servo cable exits the elevator frame.  These two gussets were installed on the elevator.  Also, trim tab covering was started.  U500 adhesive was added to the trim tab frame and the fabric was attached on one end.  Hours: 1.5

Ed Working on Trim Tab

Elevator covering cont.

We are gluing a sheet of fabric on one side of the elevators.   These parts are more complex than the vertical stabilizers, but we are learning what works.  Takes some time as we are trying to avoid bubbles and creases in the glued areas.   Hours 4.5

Attaching fabric to one side of elevators

Michael and Ed working on Elevators

Started Covering on Elevators

We applied two good coats of U500 adhesive around the perimeter of the two elevators.  Adhesive was also applied on the trim servo mounting/fabric plate.  Hours: 1

Ed Adding Adhesive around Elevator Perimeter

H. Stabilizer doilies & tape

We create fabric doilies for added protection at the points where the flying wires will attach to the horizontal stabilizers.  This may be overkill since we already have finishing tape at those points, but we added them anyway.  We pre-shrunk a section of fabric, then traced circles out with a compass, and cut them out with pinking shears.  The doilies were about 3.5" in diameter.

Doilies cut from pre-shrunk fabric

Doilies glued in place (2 on front side, and 2 on back)

We also glued one of the longer horizontal perimeter tapes (at the leading edge) to the horizontal stabilizers.  Ran out of time so will glue on second long tape (hinge side) another day.  Hours: 2.5

More Horizontal Stabilizer Covering Work

We continued to work on our horizontal stabilizers.   We used pencils to mark the area that needed adhesive applied.  Tape was added to make the application of glue easier and cleaner.  Three coats of the U500 adhesive was applied to the outer perimeter and left to dry.  Hours: 1.5

Adding Glue to the perimeter

Finishing Tapes on Horizontal Stabilizers

After completing the top and bottom fabric attachment on the horizontal stabilizers, next up is to attach 2" tapes over the metal support areas to strengthen the areas due to possible rubbing.  The center of the supports were identified and then a 2-1/8" band was drawn centered on the metal supports.  Three coats of the 2:1 thinned U500 adhesive was brushed on the stabilizers making sure we stayed within the drawn lines.  Once the adhesive was allowed to dry, the tapes were added.  The tapes were first attached with adhesive in the center and then worked outward from there toward each end.  Both the top and bottom surfaces were done this way.  Where tapes would overlap, we considered how the air would be passing over the surface and overlapped the areas such that the air stream would not peal up an area.  Hours: 3

Laying out Glue areas in Pencil

Working on Finishing Tapes

Horizontal Stabilizer fabric

Attached 2nd sheet of Superflite fabric to the other side of the two horizontal stabilizers.  The fabric was glued and shrunk using the same process as described in a previous blog entry.  Hours: 3

Officially Started Covering

We re-calibrated our irons which took a bit of time.  We plan to cover the horizontal stabilizers first.  We first cut the fabric.  Four pieces was cut from the Superflite SF102 fabric.  Next we applied three coats of the U500 adhesive to the outer members of the horizontal stabilizers.  Finally we trimmed and attached the fabric to the rear edge of the stabilizers.  Small bubbles were removed with a iron at 250F.  Hours: 4

Started working on the horizontal stabilizers

Removing Horizontal Stabilizer

We continued our work on getting the fuselage ready to transport to the hangar at Cox Airport.  Today we removed the flying guy wires supporting the horizontal stabilizer and placed all the hardware into labeled bags.  The two attach pins were removed, labeled and bagged as well.  The two, now free, horizontal stabilizers were set aside and will  be one of the first items to be covered with fabric.  Hours: 0.5