Waiex-B 0022

[WaiexB22]

For the panel...I have been putting of cutting holes here for a while. I think the time is going to have to come soon to stat putting things in. Here is my current plan. The throttle and trim are not shown, but the will be on the bottom left (setup for flying English).

Does anyone have experience with the AV-30 vs. a Garmin G5? I can't decide which I prefer.

I have removed the fuel tank to install the components on the firewall. It needed to come out for the service bulletin on the straps on the b model anyways, so no real biggie. It will give me a chance to add a fitting to the top of the tank for an auxiliary tank, since I am planning to install one behind my seat. I have the fuel pump components as well. I am running 2 fuel pumps in parallel for redundancy. I am also running dual filters with one on the discharge of each pump. There are check valves built into the pumps and plenty of people flying this engine rely on that check valve to maintain pressure in the system. Personally, I think that is a bad idea, so I am running an external check valve on the discharge of each filter. A rough sketch of my fuel system diagram is below. The fuel pump setup is a little heavy (about 5-6 pounds total), but I think it will be robust and reliable. Considering fuel supply and delivery accounts for most engine failures I want to make sure I always have a good stable supply of fuel. I have been holding off assembling the fuel pumps until I'm not doing so much dusty fab work, I don't want to get garbage in my pumps.

Hangar space in my area is limited to say the least. I lucked into a hangar because the guys ahead of me couldn't fit and I got wind of the opening through my local EAA chapter. I went ahead and secured the spot in a shared hangar at 14A in Mooresville, NC about 20 minutes form home.

[sonex892.]

Cant help with the avionics.
Your fuel system is similar to mine with a 32 litre tank behind the seat. I mostly leave the aux tank out of the aircraft.

Instead of transferring fuel I manage the fuel with a 3 way selector valve mounted to the firewall, the actuator shaft is extended to under the instrument panel. OFF / MAIN /AUX.

I chose not to transfer from aux to main, my thoughts were it eliminates any chance of pumping fuel overboard. It also helps with trimming, I generally take off on the main then go to the aux and alternate supply every 30 mins. The aux pump is never required it is purely a backup should the Jabiru engine driven pump fail.

[WaiexB22]

Thanks for the suggestion! Generally, I like the simplicity and flexibility of your system. The biggest problem with direct feed from the aux tank in my situation is the lack of elevation to create suction head at the pumps. The aux tank will sit down low in the back and the fuel pumps are on the firewall at or above the outlet of the aux tank. I plan to make the aux tank permanent.

The other reason I am using an aux tank is that I hope to fill through a fill port on aft side and then transfer fuel to my main tank. I hope to significantly reduce the number of times I refuel around the windshield that is prone to crack when fuel gets spilled on it. I am planning on using a BIG transfer pump with big AN lines to move the fuel as fast as possible. The idea being that I can transfer on the ground during taxi if needed for W&B. With the prop I'm running I don't think it will be a problem, but time will tell. I will be running ethanol free mogas that I carry to the airport in a tank in my truck. 95% of my flying is within an hour of home and for fun, so I think my typical fuel burn should be around the capacity of my aux tank. Then when I do fly a cross county, I get more range to search for mogas.

Having said all that, I considered using the aux like a header tank in a high wing, where I fed the main tank through a small aux tank in the rear, then feed the fuel pumps from the smaller tank and place them in the back. I wouldn't need a transfer pump it this case, but I would have to fill through the windshield all the time. Also, I don't really want high pressure fuel lines in the cockpit that have to run to keep the engine running. A transfer line is different IMO because it can be shutoff with no adverse affects on the engine running. Lastly, the W&B might be a problem with no fuel in the main tank and the "aux" tank in the rear full.

[flyguy0609]

It would be really nice to have just another hour of fuel. Like 8 gallons. So I looked at it. THe Sonex meets the +6 G aerobatic requirement at 950 pounds. That is the equivalent of 5,700 lbs. Divide that by 1,320 and you get 4.318 G's That is just under the utility category 4.4 g requirement. Structurally OK. I was thinking about an auxillary tank 8 gallons. I ruled out tube tanks in the wings for a couple of reason. First the ratio of structural weight to fuel weight is not good. Second (and more importantly) is that in the case of a spin, the fuel in those tanks will flow to the wing tips, making recovery problematic. The Yankee AA-1 was spin restricted because the tubular wing spars which serve as fuel tanks. That is not a part of the flight envelope I wish to explore. Next best spot is behind the pilots seat. I then read a post (some where on this forum) about a long XC flight with the new pilot, an instructor, baggage and aux fuel behind the pilot seat, which require nearly full forward stick to maintain level flight which concerned me. I decided to model the resulting cg. With 350 lbs pilot & pass, 40 lbs baggage, 102 lbs main fuel, and 48 lbs aux fuel. For modeling the cg, I used a moment arm for the aux fuel that was at the midpoint between the Pilot/Passenger seat and the baggage moment arm. With 48 lbs aux fuel at take off the cg was at 95% of the full aft position. As the fuel burns off the cg moves further aft. When the main tanks are half full, the cg has moved to 99% of the full aft position. Personally, I'd rather make an extra fuel stop. I think it would be a good idea to get out your cg calculator, add an extra line for aux fuel, plot a number of scenarios.

[WaiexB22]

Thanks for the comments on the W&B! I do have concerns under certain circumstances especially considering my engine and FWF weight is only a few pounds heavier than a rotax. I also have concerns for W&B in the event of a transfer pump failure if I take off with full fuel. Generally speaking I do not intend to run around my local area with 28 gallons of fuel on board. This is something I will need to explore fully once I have the plane fully built and I have some actual weights to work with. I have it ready to go on the gear, I just have been procrastinating because they are a tripping hazard in my little shop while I work on engine stuff. I also can't rig my wings up in my shop. All I have right now are other peoples numbers.

Does anybody have any weight and balance with the wings off and/or know what the wings weigh and where their CG is?

I am doing a few things that I hope will mitigate the weight in the back since it seems there are almost no nose heavy Waiex out there.

1. I have decided on an airmaster prop and it is 28 pounds right on the nose.
2. My engine mount is about 4 pounds heavier than the typical sonex mount.
3. I am putting the batteries, fuel pumps, and smoke oil tank under the cowl.
4. This is a B model. There is less data that I could find, but it seems the b model has a little bit more weight up front than the a model.

For my mission I don't need two full size adults and baggage and full fuel in the plane. I have young kids and my wife doesn't like to fly with me much right now on account of the kids. Even if she did she is small. If my kids come, I have at least 5 years before one of them is going to weigh 100 pounds. Most of my cross countries will be solo. Since I will be running mogas having the ability to load up solo and extend the range would be very nice. If I was running 100LL and/or had better availability to mogas I might not do this. Also, I figure If I want, it is easier to remove one that's there than add one later.

[WaiexB22]

Time for an update.

I decided to keep things simple and I abandoned the constant speed propeller. A ground adjustable would probably be a decent choice, but I just don't like them. I am likely going to order a fixed pitch prop from Catto. I have been working back and forth with Catto and hope to have something finalized and in production soon.

Also in the name of simplicity I abandoned the auxiliary fuel tank. I installed the new fuel tank straps that were part of the service bulletin and I am working on a shutoff valve that I can access from the seat in my harness. The fuel pump and filter assembly is ready to install, once that goes in I can make fuel lines and the fuel system will be done.

I started mounting instruments in the panel and started laying out my electrical system.

I installed the control sticks. I flew a plane recently that utilized quality bicycle grips on the control stick. I love them!....and I had to have some. I like a standard round handle with one button on top. The fighter grips, and contoured grips just aren't for me. There are some nice foam ones and a few rubber ones for 1-inch tubing, but the options are limited and and not nearly as comfortable to me. Problem with the /bicycle grips is they are made for 7/8 diameter tube. I cut the old ones down, made a jig, and welded a piece of 7/8 tube on to the factory units. I left them long for now and I will trim them later when I get a better feel for where I want them. I love the feel of these grips. I have PTT buttons for the top center.

I also have the throttle cable and attachment brackets fabricated and mocked up. This engine has a sensitive throttle and I wanted precise control during cruise, so I opted for a macfarlane vernier throttle. The other issue was the throttle body was spring closed....and it was 2 strong springs. I guess Yamaha didn't want the snowmobiles taking off at full throttle in the event of a failure for some reason ;). I removed the springs and the the throttle body has no resistance to movement at all. I think the intake vacuum would still close it if the throttle cable falls off, but I think the chance of that happening are very unlikely when there is almost no force on the connection. I thought about adding springs to open, but I don't think it is worth it as I believe it would increase my chances of causing binding and or some other issue. I am comfortable with what I have. This conversion also required that I move the cable to the opposite side of the throttle body and increase the travel distance at the throttle body (the increased travel distance helps with the sensitivity issue too). There is a bracket off the starter to hold the cable at the fixed side and a bracket off the cam to provide a lever for attachment. The throttle is smooth as silk and works beautifully.

[Murray Parr]

1. I have decided on an airmaster prop and it is 28 pounds right on the nose.
2. My engine mount is about 4 pounds heavier than the typical sonex mount.
3. I am putting the batteries, fuel pumps, and smoke oil tank under the cowl.
4. This is a B model. There is less data that I could find, but it seems the b model has a little bit more weight up front than the a model.

Just be careful adding extra weight. I thought I was going to be lighter than most other Sonex's because I never added anything fancy and installed the lighter Rotax engine but still ended up with an empty weight of 335 kg (739lbs). I have now put myself and my Waiex on a diet and so far, have reduced my weight by 3kg and the Waiex by 7kg and hope to remove another couple of kg by redesigning some of the firewall forward stuff. I have the Rotax up front but even though it is light, the systems required to run it can quickly add lots of unnecessary weight.

Have a look at E-Props before you decide on prop choice, I lost 5kg just by switching out the fixed pitch Sensenich for a 64" adjustable, performs slightly better too.

For those that don't speak metric, just multiply the kg by 2.205 to convert to pounds.

[WaiexB22]

Progress has been slower than I would like, but steady this summer. I have most of the firewall forward components mounted. The fuel system is complete minus the sump and 2 -6AN lines. The coolant system needs a T welded up that is sitting on my bench. The oil system needs 3 hoses installed that are also sitting on my bench. I have the ECM, engine monitor, and engine wiring harness ready to go. I am currently working on power distribution wiring. I am making a smoke oil tank for the left side of the engine firewall, opposite the engine oil tank in the photos below. I plan to run a small in-tank pump for the smoke oil. I am waiting on the pump to be able to finish that. As soon as I get the oil tank done I will wrap up the radiator inlet duct and the cowl modifications. Once the cowl is done, I plan to pull the engine and mount so I can powdercoat the mount. (I tried painting it and it just isn't holding up). I also picked up a second engine that was just rebuilt by Hauck Powersports using all new Yamaha OEM internals, sensors, and coil packs. Once the mount is powdercoated I can reassemble and install the new engine and ECM. Once that is done I should be in a position to run the engine.

[Bryan Cotton]

Progress has been slower than I would like,

Odd, that never happens here! What's the right font to depict sarcasm? I always forget.

Looks great!

[WaiexB22]

Thanks Bryan! I just always seems like it will "only take a few minutes for this part"...hours later I'm finally willing to accept the third rendition.