Here’s the latest update from the last week or so..
- Routed the fuel lines in the fuselage
- Tidy’d up the fuel lines with some zip tie and fuel line stand offs
- Spliced an extended the fuel pump wire, it was too short to reach around to the other side of the pump
- Added heat shield to the oil lines
- Trimmed the windshield to fit and get ready for bonding
I’ve been traveling a lot in March and the weather has been quite cold here in the Denver area. We’ve been getting record amounts of snow here!
Anyway, a short video of the latest items I’ve been working on.
Thinking video updates are better to do than writing updates with pictures. Plus, seems it’s a bit easier to provide context.
On a cold and snowy morning, my friend and I unloaded the Sling TSi into hangar at KCFO, bringing this build into the next chapter!
The paint looks phenomenal! If anyone is interested in the colors, it’s Sherwin Williams metallic colors.
- Phantom Gray
- Nobel Red
- Las Vegas Gold
- Black Radiance
I was able to get out to Hayes Aviation in Akron, CO to check in on the paint progress.
They are finishing up the detail work and about to throw some paint on!
They already did the vertical stabilizer and WOW.. I'm digging the base color - Sherwin Williams Metallic Phantom Gray.
They'll be adding Metallic Nobel Red to the bottom of the fuselage with a Black accent stripe with some Las Vegas Gold accents. Can't wait to see the final product!
If things go smoothly, then I might be able to pick it up late next week and take it to my hangar at KCFO.
I'm ready to get back to work!
While I was hoping to get my plane back before the end of the year, it has been taking longer than expected to paint.
Several things got in the way.. rivet hole filling, unexpected leave from paint shop folks, and the holidays.. I’ll just chock it up to 2020 luck. 🤷♂️
Either way, I’m hearing some good status updates from Hayes Aviation. Turns out they primed it twice for a better finish and helps identify any initial problem areas.
I’m hoping I can head out there the first week of January and they’ll have one side taped up with the lines. Once I approve, they will spray the colors and it should be ready to load up shortly after that!
I’m a member of the Denver EAA Chapter 301 and it worked out perfectly that the current build in the chapter hangar was finishing up.
I started my search months ago for a hangar and it’s almost impossible to find in this area. Centennial has over a year wait list and unfortunately you’re not allowed to do ‘maintenance’ on the aircraft at a tie down / covered location.
A huge thank you to the local chapter for allowing me to use the space!
The day finally arrived! I was able to get all the exterior components ready for paint - except the windshield. The Sika primer never arrived on time, so the paint shop will just have to seal that up really good.
My son, Ethan, had a blast sitting in the 'big truck' and honking the horn. Glad he did, because he got the neighbor's attention.
It was just me out there and I was going to try to figure out how to get the plane in with a winch and pulley system of some sort... Not exactly a one man job.
Luckily, I have curious and helpful neighbors that came out and offered assistance!
My winch actually ended up breaking at the handle, so another neighbor went and got his. By the end of the event, I ended up with 5-6 people out there. ;-)
Finally was able to get the fuselage in and secure it with straps using the side wall slats.
The next morning I loaded the wings using the wooden stands I built and secured them against the wall.
It's nice to have an empty garage - just in time for snow season. Don't have to clear off the car anymore!
When I arrived at Hayes Aviation in Akron, CO, a few hours outside of Denver, he had a full team of people ready to unload the truck. It was bittersweet leaving the plane there, but I'm looking forward to the final result!
In order to fit the windshield, I need to get the front fuselage cover on.
Since it's just held on by rivets, I could imagine some water getting pushed through this section, so I decided to add sikaflex for a solid seal. It's messy, but worth it.
I did have some trouble fitting the parachute rocket all the way in since the cables that connect to the bottom of the rocket push on the housing. The trigger doesn't line up through the hole on the bottom.
I gave up trying to do it while attached to the plane, so I took off the rocket housing and was able to fit the rocket easier. Scary nonetheless handling a live rocket. Glad that's done!
I lined up the parachute blast skin and drilled the holes into the fuselage and canopy. The factory recommends that you use some PVA release agent and apply some clear silicone underneath the skin to prevent water seepage.
Just doing some final riveting on the wings, attaching the fuel tanks since they passed the pressure test.
I was going to do the Service Bulletin 14 - replacing the aluminum rivets with stainless steel ones on the spar carry through, but it seems that the factory already did that for me in my quickbuild. Note the darker rivets with rounded edges compared to the same size rivets nearby.
Continuing my exterior component adventure, I decided to focus on fitting the wheel paints and the tail cover.
The hole finder came in handy for this exercise. I've seen quite a few different ways, but this seemed the most logical and I didn't have to 'redrill' any missed holes!
The tail cover was straight forward, just line it up flush against the vertical and horizontal stabilizers and drill.. fill with rivnuts.
In preparation of getting the airplane ready for paint, I'm focusing on the exterior components.
I took the fitted cowling and put in the camlocs.
It was a bit tricky since I'm not using any of the 'easy' tools. I basically used my fingernails and some needle nose pliers to get the retaining ring on and some locking pliers to squeeze the camloc screws and fit them in. Not easy, but it's possible!
In addition, I secured the metal vent on the top. It's coming together!
I am working to finish up the firewall forward electrical and any final placement of the wires that will be covered once I put the front fiberglass piece on.
I had to reroute some of the heater ducting and also remembered to attach the heater control cable.
I also routed the brake line through the firewall forward gromet.
One thing to note, and I've heard about this from another builder, the bottom muffler bracket that mounts over the muffler shroud is a manufactured incorrectly - it's a bit too big.
The fix is to shave off some of the metal where the bolt joins them, maybe a quarter inch total. It didn't take too long with a grinder and it fit just fine afterwards.
It's been a busy few weeks working on the fiberglass components of the airplane.
The main goal is to get it 'Paint Ready' before November.. tick tock!
That means riveting on the cowling components, putting in rivnuts on the wheel pants, installing the wing tips, etc..
The most time spent was on the wing tips. I used the straps to push them into the place against the leading edge of the wing in addition to widening the wing tip to match the shape of the wing.
Once in place, I match drilled the holes and then countersunk the fiberglass. There were parts that weren't reinforced with the second layer of fiberglass underneath, so I figured I would add some additional strength by applying SikaFlex to the bonding of tip to the wing.
Some other items I worked on were the ECU mounting and shaving off enough muffler to slip in the factory supplied muffler extension.
Lastly, my Fuel System arrived! This is the last bit of components I'll need to finish up the plane.
I inventoried the components and some fittings were on back order, but overall I can make a dent in the installation here soon.
Next up, I'll be permanently mounting the cover over the heater section so I can trim the windshield and I'll also be adding the fasteners to the cowling to the fuselage.
I decided it was time to risk my life and mess with a live rocket...
I read the instructions provided several times before I took the rocket out of the protective cage and inventoried what I needed.
It was pretty simple to put together actually, you just need to install the firing pins and the trigger, and attach the cable that pulls the chute.
However, installing the rocket into the canister proved to be quite difficult.
The cable rings at the bottom protrude enough that it's hard to fit it in the white canister, so had to squeeze them a bit. However, when the trigger reached the bottom, the hole didn't align with it since the cables were 'pushing' the rocket to one side of the canister.
I'm not going to try to force it in it's current state since it's a bit awkward to get to. I thought I was saving myself time by mounting the canister to the aircraft, but really it's just not enough clearance to work with.
I'll be unmounting the canister and reattempting assembly on the table.
Now that I'm getting close to permanently mounting the fuel tanks on the wing, I thought it would be a good time to pressure test them once again.
This time I used the method that Pascal Latten mentioned in his blog with a manometer.
I blocked one of the fuel connections with an AN-6 Cap, then connected some hose to a barbed fitting and put some water in the line.
I then connected a smaller hose to the overflow and blew into it. Not much pressure, just enough to raise the water a bit.
Then just use a measuring tape on the wall and some tape to mark the starting and ending positions.
Take note of the date, temperature and atmospheric pressure.
Depending on the temperature and pressure differences over the next 24-48 hours, the water level will vary.
I kept mine connected for 3-4 days each and didn't see much of a drop below a certain point so I figure it was a solid seal.
It's time to make the plane look sexy! Love this cowling's aggressive looking design.
First thing to do is drill some holes to mate the top and bottom pieces, just lay it on the ground and make sure the leading edge of the cowling is aligned, then work your way down to the rear and drill some holes. Measurements for the holes are provided in the manual.
The cowling comes a bit too big and will slip over the fuselage a bit, so you'll need to mark it for trimming.
First thing to do is fit your fiberglass piece that connects to the windshield and covers the front part of the fuselage.
From there, use some painter's tape to mark the leading edge of the fuselage.
Now you can fit the cowling to the aircraft and secure with clecos.
I didn't have a second person to assist, so I found a metal rod that was about 5mm in diameter and fit that in between the prop and the cowling. I also needed to support the cowling, so used some ratcheting straps over the prop. Worked out pretty well and stayed relatively still while working the back.
Next, you'll want to squeeze the cowling to match the form of the fuselage, so use another ratcheting strap around the rear of the cowling. Then, you can finally lay another layer of painters tape on the cowling, making sure the line up the rear edge of the fuselage layer of painter's tape.
The idea is that the painter's tape is the same width, so you'll know where to trim the cowling.
After that, I used the dremel bit 543 to shave off the painter's tape.
It did take some fine sanding to get the cowling to line up evenly on all sides.
Next up, I'll need to mark off where the Camlocks and Dzus connectors will attach.
When mounting the engine, the bolt that is nearest to the turbo needs to be trimmed a bit.. maybe a half centimeter. Be sure to measure 125mm from the bottom of the bolt head instead of the top. I initially cut mine too short and had to order another M10x130mm bolt from Bolt Depot... oops!
Once that was done, I swapped the coolant outlet at the back of the engine that comes with the kit. Otherwise, you can't reach the bottom bolt with the wrench as that is in the way.
Next up was connecting all the oil lines. Be sure to twist the AN fittings to the correct direction before tightening them with the ear clamps.
Also, be careful when you remove the yellow stoppers - there's a good cup or so of oil left in the engine from when the factory tested it. Just have a collection cup ready and 10 mins to spare to catch all the oil that drains out.
It's a tight fit on the left side getting the wrench in there to tighten the AN fitting. The right side is impossible to get to unless you remove one of the exhaust pipes.
They detail how to do this in the manual. It's pretty simple removing the pipe clamp and loosening the bolts on the engine.
I wanted to start fitting the cowling, but first needed to get the propeller mounted. Be sure to follow the Airmaster manual for this.
You'll need Aeroshell 22 grease and some anti-seize grease. The firewall forward kit does come with Copper Slip, which is what I used on the propeller lugs to prevent rust and ease of future disassembly when needed.
However, when inserting the lugs, make sure to insert them with the bolts, otherwise you won't be able to fit the bolts through later. I also recommend using the lug fitting tool that comes with the kit, don't push the bolts from the back, use the bolt threads to pull the lug through with a straight even force. These aren't easy to get in and require some decent pressure to get them set.
I was surprised that the propeller doesn't use any thread locking fluid on the bolts. Instead, they use the Nord-Lock washers. Apparently their design prevents any loosening from vibration and require more torque force to unscrew than to lock in.
After that, I put on the propeller hub and loosely fit the bolts for now. I need to get a crow foot wrench adapter for my torque wrench because the wrench won't fit between the prop flange and the engine.
Next up was some grinding.. removing the pipe below the welded section was easy, but it's not so easy getting to the section below the piece that sticks out. With that thickness in metal, it's going to take quite a few dremel metal cutting heads... I'll get to that eventually, but at least now I can fit the cowling!
I drilled the 4 holes on each side where the manual says to do. Not a perfect fit, but will trim that later.
I fit the latches to the front so I can put the coolers in front. I also drilled the hole in the top of the air filter and fit it to the plastic element provided.
I was inspecting the fuel pump on how the connections are fit. The stock 915is fuel wire doesn't have enough length to reach to the other side, so I'll have to splice and extend that to fit.
It feels great to finally see the engine mounted! Starting to feel like a real plane.
Before mounting the engine, I wanted to revisit the nose wheel movement. It was still a bit stiff and took a few pounds of force to move it. I was thinking I don’t want the rudder to stick during flight, so it was timely there was a discussion on the Sling Builder’s Facebook group on the issue. The idea is to take a 2” dowel, about the same size as the nose wheel, sand it down a bit so you can staple some sandpaper to the dowel. From there, insert it into the assembly and rotate it until you get smooth turns. What a difference!
From there, I torqued the nose gear assembly to the firewall and it was time for the big moment - mounting the engine!
Note: the engine did come with a bolt, mounted to the fairing just above the turbo that is held on by a rivet. Be sure to drill that rivet out and remove the bolt, it’s only used for mounting to the shipping crate.
Once the engine was mounted, I started assembling the oil hoses. It’s nearly impossible to get them on without any loosening. To help with that, I just put one end in boiling water for a minute or so and then lubricated the barb and hose with some oil. Be sure to slide it on in one quick movement.. it’s really hard to get the hose off once on the barb.. trust me. ;-)
The intercooler assembly is pretty straight forward, just connect the hoses and mount it in the approximate location.
Next up, mounting the propeller and fitting the cowling.
It’s like Christmas Morning when you get that phone call.. “the truck will be arriving in the next 30 minutes...”!!!!!! I’ve been anticipating this day for a while since this final shipment contained the finishing touches that transform the plane from a aluminum form to a luxurious efficient fast flying machine. 😎
Soon after the parts arrived, I began inventorying and stapling them to the parts board. Everything is there (except the fuel system 🤨 ugh..). Apparently the factory is revamping the fuel system kit and it’s a “TBD” on shipping date, but I have plenty to play with until I press on that subject.
I’ve made quick progress on the Firewall Foreward, despite having a Sling 4 Firewall - basically just had to move the oil tank to the right side and drill a few other M5 Rivnut holes.
They did send me an extra silver adhesive foam, so I decided to double it on the front and back of the firewall for some extra sound protection.
The Upholstery looks awesome with the grey tones and red trim along the edges.. looking at paint schemes to similarly match!
Next up, finishing up the firewall forward items and lifting up the engine for mounting!
It was exciting to get the rocket & parachute! Installation was pretty straight forward. The key for dropping the parachute in the box is to put a strap around it (temporarily) to be able to place it in there and lift it out later if needed. You definitely DO NOT want to pull on any straps from the parachute itself, otherwise it's an expensive repack.
I installed the rocket holder with the correct AN bolts, this is a bit of a pain since your fingers cant reach in between the rocket and where you put the bolt through, so I used a magnet pen to hold the washer and nut in place.
After that was done, I used zip ties to secure the parachute bag to the frame. The holes lined up perfectly and I used a flathead screw driver to help pull the other end of the zip tie out. I visually inspected to make sure the zip ties went through the bag straps.
I did route the cable through the airframe and secure it, but will hold off on installing the rocket until I read up a bit more on what triggers it. I definitely do not want me to try to install it and that thing go off and put a hole in my house. ;-)
I am also waiting on the carabiner to connect the rocket cables to the parachute. Seems that they missed that item when packing my components. Until then..
I finally decided to try my hand at some metal work again. It’s been a bit since I had to rivet or cut any aluminum, so I was a bit rusty.
A huge thanks to Phillip’s blog showing the steps to install the missing inspection door for the pitot tube.
I certainly wasn’t as precise as he was, but mainly I measured the placement recommendations from the factory and traces the outline of the cover.
From there I tried my best to find center. I knew it wouldn’t be perfect so I intentionally set the nibbler to be a smaller diameter than the cover. Once done cutting, I just used the file to get the hole to match the drawn outline.
I did use a handy pull rivet style dimpler, which made things really easy to get flush rivets in there.
Once everything was dimpled, I just drilled the holes for the rings and viola!
So during my move to Colorado, I did have some damage to the vertical stabilizer skin - a nice hole on the side and some major scuffing on the skin. I ordered the new skin back in April and it finally came last week.
I made sure I had some sharp drill bits and started de-riveting the skin.. ugh.
While I have the skin off, I’m going to remove the VOR/ILS antenna since I decided to use the GNX375 (GPS only for approaches) instead of going for the more expensive option of the GTN650. That’ll save me about 3lbs of drag! ;-)
Not much of an update this week. The main item I accomplished was to run the remainder of the RG400 to their respective locations and add the BNC and TNC connectors.
I installed the GPS antenna in the rear instead of the proposed location in the manual due to several factors and mainly a strong recommendation from MidWest Panel Builders below from Adam.
Words of wisdom:
We very strongly recommend against having the antenna under the cowling. We have seen time and time again issues caused in this area. It’s not the fiberglass that’s the problem, actually.
The main problems are:
When considering Garmin’s installation recommendations, they give you the order of importance of items. Being that avoiding shadowing is higher on the order than distance from COM antenna, it is acceptable to put it in that location. Plus, we have had plenty of installations by now with it behind the canopy with good success.
The second GPS antenna, being how different it operates can go under the cowl. Its small size lets it sit far enough forward on that bracket to work well.
This week I focused on getting most the antennas installed and wiring up all the connections.
I installed the Comm1 Antenna on top and made the RG-400 BNC connection. I then test fit the parachute skin and it looks like that may be a tight fit. Will have to make sure I figure out where that goes before I fully secure the antenna. Additionally, I’ll need to put in some rivnuts there since there’s no access to the bottom of the antenna.
I then installed Comm2 on the belly between the ELT and center channel. The antennas come with hole templates for mounting, so it was pretty simple to drill through to size.
The Transponder / ADS-B antenna was a bit more difficult to mount. They have a hole pre-drilled on the center bottom of the fuselage, but with the inside skin, it took a bit of work to create holes for access to the mounting screws. I used a 1/2 inch drill bit on the inside skin to get it big enough for a socket wrench to fit and secure the bolts.
I then turned my attention to figuring out the wiring diagrams and crimping the pins for the Delphi connectors. Took a bit to get into the rhythm, but eventually figured out how to crimp without the right crimper - I had a molex crimper and apparently these type of pins require a bit more expensive tool. The Molex crimper worked, but it took about 4x the time.
I finished up the canopy wiring and installed the lights. The front ones were easy since I just had to mount them with 3 screws each. The back lights took a bit more work since I had to enlarge the hole and clear some styrofoam to give it a flush fit.
Since my pilot light dimmer is on the panel, I now have an extra hole in the canopy I get to work with. I figure I install some sort of power source for a GoPro camera, so I spliced the power from the rear lights and ran some wires there.
I was able to order my battery! I decided to go Lithuim since the weight savings is pretty drastic. The Rotax 915 requires a battery with at least 350 cold cranking amps. The ETX900 battery fit the bill with 400 CCA’s and only 4.9 lbs! Bonus, I was able to get the 10% AirVenture discount. Good timing!
I decided I might as well get to doing Service Bulletin 17, which has me replace the aluminum rivets in the elevator control stops to stainless steel. To do so, I had to remove the ribs in the center console that hold down the elevator torque tube. After that, drilling the rivets out was easy with a flexible 90 degree drill bit.
The service bulletin didn't specifically specify, but I decided to use some anti-corrosive on the stainless steel rivets since it will be in contact with a dissimilar metal.
I was not fully satisfied with the stiffness of my elevator and wanted to make sure it was butter smooth this time. While I had the elevator ribs out, I decided to give them a good shaving around the area that holds the torque tube bushing with a dremel. I tried fitting a few times and sanded a bit more. I finally got it to where there's zero resistance! Definitely happy I got that resolved.
Before you install the side panels, the factory suggests using some high density foam to block open areas in the rear passenger air channel. I couldn't find any decent foam blocks, so I decided to get some polyurethane based foam. It did the trick and shaving it to size was easy with a hand saw.
Next I moved on to starting to wire up the canopy for the front and rear lights. There's a tube that routes from the back left of the cockpit through the canopy and exits in the center between all the light holes. Not too easy to see in there, so I used a wireless borescope to understand what I'm working with. I had to punch some holes through the styrofoam in the canopy to get the wires through to the front pilot light areas. The rear passenger lights were easy since the tubing routes by the hole. I'll put on a protective sleeve on the wires that exit the canopy and route them below the rear seat for connection to the harness.
I was really excited to get the avionics mounted and wired up. It would also let me know the proper placement of the wiring harness so I can secure the harness to the fuselage’s channels with zip ties.
I did have to get some angled aluminum from Home Depot to help secure the doubler plate on the back to the rib flange, but that was the only item that required a bit of work.
It took me all of 20 minutes to wire up all the avionics on deck! Can’t thank the guys at MidWest Panel Builders enough for their work on the harness!
It is a few steps ahead, but I wanted to see how it looked with the upholstered dash and the avionics panel. Looking good!
I’ll be taking those off so I can do the firewall forward kit and engine.. expected to arrive in September.
Until then, I’ll make sure all the wires and pitot static lines are secured in the channels. I already started with the passenger headphone jacks. The sticky square zip tie things come in handy! Just stick it on and run the zip tie through the channel.
I’ll also be working on some of the Service Bulletins that came out for the wing spar rivets and the elevator stops and replace the aluminum rivets with some stronger stainless steel rivets.