Vertical Stabilizer Skin completed

1 hr. - Flipped the VS over and inserted all of the rivets, and began finishing up the skin.

And it's done!

Installed both antenna rods to see how it looks:

Vertical Stabilizer Skin

3 hrs. - It's been almost a month since my last post.  Life's kept us busy!  Had some down time with the Sonex engine I wanted to solve, and working away on my wife's office.  Good news is the Sonex is airworthy again and back in the sky.  I'll post about that soon.

Had to complete the VOR/GS/LOC antenna cable end before closing up the Skin.  When I ordered the antenna and cable, I also purchased the wrong fitting.  I needed Male ends but got female.  Thought I had an extra one at my hangar...and I did...an extra Female end.  Another order from Aircraft Spruce, and now the cable is terminated and connected to the antenna puck.

Skin is fitted and then I could enlarge the openings for the antenna rod exit holes.

If you look closely at the top, you can see the VOR/GS/LOC antenna rod sticking out.  These thread into the puck thru the Skin, and have a Allen set screw that locks it in place.

I reamed out all of the rivet holes, deburred the skin and structure and primed the inside Skin.  It's not pretty but also not meant to be visible, just cut down on corrosion.

Rudder Fiberglass Tip

1.5 hrs - After consulting with Craig M on the type of strobe he's using, I went ahead and made a new backing plate.  This gets connected to the fiberglass tip with two rivnuts.  The plate that TAF sends has multiple holes punched, none of which align with the 1.75" distance for the mounting holes on the AveoFlash posistrobe XP unit.

Next was to rivet the tip on with the filler panel (aluminum).  Don't forget to run the pull wire!

Rudder Skin (from Feb. 16, 2017)

2 hrs. - Forgot to post this last month...completed rivetinfmthe son of the rudder to the structure.  Began fitting the fiberglass tip, but quit when I looked at the strobe backer plate...need to research the make of strobe I plane to use.

Flying my Sonex N629SX

While there hasn't been much time for building on the Sling, I have been keeping up my currency in the Sonex.  Gone flying twice in the last week...yesterday Liam went up with me again and we buzzed around the Honda R&D campus where I work.  The picture shows the layout of R&D and in the background is the Marysville Auto Plant (MAP) where's the Honda Accord and Acura TLX are manufactured.  To the right of the R&D campus is Transportation Research Center (TRC) of Ohio.  It's a jointly owned facility between Honda, and Ohio State University - that is used for product durability testing before cars go to mass production.

Vertical Stabilizer Structure Complete

2 hrs.  - It's been over a month since any work was done on the Sling 4.  We've had a major diversion with the remodeling and tenant finish of my wife's new office fo her medical practice.  That project has made some great progress...so this afternoon while "relaxing" I decided to step out to the garage and complete the vertical stabilizer structure.  I had previously finished the rivnuts and the forward spar and ribs.  Completed reaming out the hole s in the multiple parts of the rear spar.  Made sure I noted the holes not to rivet, and finished riveting the rear spar structure to the ribs.  Also reviewing the plans I noticed missing a doubler plate for the top rib, for the Glide Slope / Localizer / VOR antenna puck.  This is now complete.

Rudder structure begins

2.5 hours - While I wait for the new / replacement Rivnut tools...I started on the rudder assembly.  Began by preparing the spar and ribs, spraying with primer, and then bringing the parts home to complete in my garage workshop (where I built the Sonex).

This is what the structure looks like riveted together.  The tip rib is offset with the counterweight at the end.

Vertical stabilizer - rivnuts

1 hour - Received a new nut puller (rivnut) tool for Christmas.  After using it on 6 rivnuts the mandrel for the M3 inserts broke on me...not too happy about that.  I ended up purchasing a better tool (the one Craig M. recommends) and in the meantime the vendor responded today they will send me a replacement M3 mandrel.

Needless to say I wasn't able to complete these parts and the vertical stabilizer structure.

Links to Sling Builders

Craig M - Sling 4 Build (USA)

Pascal Latten - Sling 2 Build (Netherlands)

Jim Pavlick - Sling 4 Build (USA)

Peter Calley - Sling 4 (Australia)

Gord L - Sling 4 (USA)

The Airplane Factory (South Africa)

Vertical Stabilizer - assembly begins

4 hrs. - This post combines about three separate days of activity spread over as many weeks, interrupted by my trip to LA when I got to fly the Sling 4.

First steps were unpacking the VS parts, then prepping and priming (did this before my trip).  I then started to assemble the the spars and ribs...and riveted the front spar, nose ribs and main ribs 1-3 together.

I plan to build my Sling to IFR capabilities, so the tip rib of the VS gets a VOR/Localizer/Glide Slope antenna for navigation and landing aid.

The last picture is my helper...our German Shepard "Bear".  He likes hanging out at the hangar!

Flying the Sling 4!

Wanted to give a quick update.  Visited with Matt and Jean at TAF on December 6th.  I planned to take a lot more pictures and videos...but:

Once we got in the airplane, Matt  pulled up the electronic checklist, and let me do everything from engine start, to taxi, run up, takeoff, and we flew for a good 45 mins. 

I did three landings - two were touch and goes, one was to a full stop on the short runway (29L).  

With two of us aboard, OAT was around 60F, at 115% power and the electronic prop control on T/O we climbed initially at 80 knots around 1200 FPM.  The sight picture isn't good at that pitch, so we nosed over for better sight over the front, at 90-95 knots, and we reached the pattern altitude before even turning to the downwind leg after takeoff for the departure to the west.  

We went out over the edge of the Pacific Ocean and flew down to Long Beach harbor - I did a few steep turns.  Then we slowed back down, hung out full flaps and did a power off stall.  It buffeted a little and dropped the left wing at 50 knots...The recovery was easy, it didn't have any adverse Yaw or reaction to stall recovery.  Simply drop the nose and it starts flying. Add power and start climbing again.  

Full power (100%) without the engine in the extra boost phase used for takeoff, we leveled out at 4000' and cruised at 126 knots IAS.  TAS was 135Knots.  You change the prop control to climb after you leave the pattern and it reduced RPM to 5500.  We dialed the control back to cruise and the RPM came back to 5200 +/- and the fuel burn reduced to around 5 gph.  

It's a very quiet engine/ airframe, reminded me of a turbo prop, or a video game. Very little engine vibration, climbs very well with just two aboard, and has distinct handling (no slop).  

Landing was Similar to the Sonex, but it's hard to slow the airframe down.  Flap extension speed is 85 knots.  It takes full flaps to get it dirty enough to descend without gaining airspeed.   I greased 2 of the 3 landings.  The first one Matt had me come in pretty high over an oil refinery that's on final, and then I slipped it down about 800', on short final.  The rudder has a lot of authority and reacts quickly when you bring it back around.  The toe brakes that they have as an option worked very well in conjunction with the direct nose wheel steering.

Did get a few pics after we landed!

Elevator Tips

1.5 hrs - this post is about completing the ends of the elevator- not about hints (tips) for building the elevator!  The directions are fairly simple and clear for this step.  Wrap the tip rib (with attached counterweight) with the forward elevator tip skin.  Cleco and rivet.  Then insert the fiberglass composite tip, position inside the aluminum skin, then drill and cleco the tip in place.  Once it's fitted then clean up the holes as needed, insert the rivets and complete the assembly (pull the rivets).  The fit was pretty good, looks like the trailing edge of each tip will need to be faired/filled to match the profile of the elevator aluminum skin better.

Elevator Skin (Left side)

2.5 hrs. - Today Liam and I worked on the left elevator Skin, which is more complex than the right.  Made sure we inserted all of the doublers for the rear channel that supports the trim tab.  Everything fit together pretty well.  The last items to do on the elevator is the outer forward skin and the composite tips.

Elevator Skin (right side)

2 hrs. - Removed the right skin fm the shipping crate, pealed off the inside film and cut away the rivet hole lines...and primed the inside.  Carefully attached the skin to the right elevator structure and only had to open up a few holes on the top of the #1 ri to avoid the trailing edge deformation as shown in the plans.  Once both sides were clecoed - I began riveting!

After finishing both sides - I then clecoed and riveted the leading edge where it wraps over the top and bottom skin.  I had contemplated dimpling this rivet line and using CCC-42 (flush rivets)...but decided to just do as the plans call for.  Once finished I trail fit the elevator to the horizontal Stabilizer...and it fits!