ADAHRS Mount and Pitot Line Bracket

The ADAHRS units need to be mounted in the same axis as the airplane and since the sub-panel sits at an angle I designed a mount for them.

The ADAHRS mount is simple, two extrusion pieces make up the legs and the rest I bent from sheet metal. The second ADAHRS will install above this one in the empty holes.

The side view shows the different lengths of the legs which makes an angle in the mount. This angle allows the ADAHRS to sit straight with the aircraft while mounted on the angled sub-panel.

I added a piece of j-channel to the back to prevent any vibration movement in the plate and thus the ADAHRS unit.

Once the ADAHRS was installed I could finish running the Pitot, Static, and Angle of Attack lines.

I made a small bracket to hold the pitot line Y-fittings. I didn't want to drill any holes in the small flange of the longeron so the bracket actually installs on the instrument sub-panel flange and then a leg bends aft to attach the fittings. Having the Y-fittings allowed me to install 90 degree connectors into the ADAHRS which provides more clearance for the big screen that is going to be installing in front of it. I just need to go back and add silicon tape to the tubes to prevent any abrasion against the outer skin.

Engine Sensors

I got the engine sensors installed, EGT and CHT sensors, in each cylinder. Pretty easy...nothing to report. Oh, don't forget the Anti-Seize before screwing in the CHT sensors....or really any time you screw something into the engine.

You can see one of the CHT sensors installed here and the baffle tie rods. I used smaller diameter star washers on the rod ends because I didn't like how the standard washers dug into the bend radius.

Baffle Material

This part wasn't as bad as thought it was going to be. My Dad was in town which gave us a chance to work on this together and the extra set of hands was helpful. For those that don't know the baffles seal the upper part of the engine creating a plenum. This makes the air that is flowing into the engine cowling to pressurize and forces it down in between the cylinders thus cooling the engine. So we don't want any gaps. The pressurized air should force the pieces of rubber together forming the seal.

Lots of planning and templates goes a long way when making the baffle fabric.

You have to cut around the cylinder. Later this will get sealed up with some RTV.

Here are a few shots of everything installed. Notice my really nice RTV job! (NOTE: you have to thoroughly clean the release agent off the material before you RTV. I would do this before you install them.....wish I would have)

Next, I made baffle close outs for the air ramps. Not sure if these will stay on the cowling or get installed after the cowling is on. I'll figure out which one is easier as I use them. But, just in case I added nutplates to the bottom.

Here is the LH one sitting in place. Two screws and it's installed.

Engine Mount Covers

The engine mount covers from Aerosport, I think, are important. They do a great job sealing the plenum around the engine mount that protrudes through the baffle. I had trouble installing the LH cover, though. I wish the flanges were double the size on the covers and this issue could have been avoided, but others have installed them with no issues (such is life). After installing the cover I realized that the nutplates were going to hit the mount, not good. So, I drilled them out and moved them. But I still wasn't happy with how close they were. So, I decided to add a flange to the mount covers. Basically, I made a ring that attaches to the cover plate and then screws into the baffles allowing the nutplates to have plenty of distance from the engine mount. Problem fixed.

Cowl Pin Covers

I got the cowl pin covers installed. They are easy; just follow the instructions from Aerosport.

The cowl pin covers look really nice!

Oil Door

You have to make the oil inspection door on the top of the cowling. The kit gives you a thin piece of fiberglass that becomes the top of the door, but you have to build the hinge and add material for strength, etc. Basically, I didn't even follow the directions for this entire part.

First, I bent a piece of 0.060" aluminum to match the compound curves in the oil door lid. This will act as the structural reinforcement of the door so the door won't bend out from the high pressure engine plenum.

Second, I epoxied the doubler to the door top.

I then started making the hinge. I wanted a hidden hinge for two reasons: it looks nicer and it provides a stop so the door skin doesn't come in contact with the cowling skin (think paint damage).

I used a hidden hinge I found on Mcmaster Carr. I cut most of the hinge part off and remade my own. Then bent legs were really the part I wanted anyway. This custom design allowed me to add a couple torsion springs; they aren't strong enough to open the door but they do keep the door propped up once it is open.

Once I got the dimensions and placement of the hinges figured out it was pretty easy.

Here you can see how the hinge itself provides the stop for the door.

The Camloc KM-610 latch heads are too shallow to protrude through the thick door so I decided to make new thicker latch heads. I drilled holes in a thick piece of aluminum to match the head of the latch and taped them in place.

I also drilled a few holes in the latch top itself so the epoxy will flow down in the holes giving a good solid connection.

I then filled the holes with epoxy.

After sanding the extra epoxy off I popped out the latches. New thicker button heads!

I made some stainless steel latch plates and riveted them in place.

When the oil door closes the latches clasp on the plates.

Here you can see a close up of the finished button heads for the latches. Now I just need a little body work around the edge of the cowling and the oil door is done!

Cowl Flap Wiring and Heat Shield

Once the cowl flaps were figured out and installed I worked on running wires to them. The wires run along the inside of the engine cowling (think high heat, vibration, grease, fuel, etc) so the first thing I wanted to do was seal the fiberglass. I used straight epoxy and just spread it around the entire inside of the cowling with a squeegee. After the epoxy was dry I painted the cowling with some high temp engine paint. Now that the fiberglass was sealed I placed a heat shield material on the cowling in the areas of the exhaust.  

I connected the wires with small #4 screws and ring terminals. I then placed heat shrink around the connection.

The wires were then taped down using smaller pieces of the heat shield. I also spread some fire barrier caulk around the wires to help protect them against heat and wear.

Here you can see how the wires travel along the cowling under the tape.

Here is the finished product. The heat shielding is sealed around the edges. Also, you can see the connector for the cowl flaps in the top RH of the cowling. The connectors is placed there so its easy to disconnect the power and remove the lower cowling. With the compound curves the heat shielding was kind of a pain to install. I had to make a couple layers overlap, but I'm happy with the final product.