Firewall Layout

[btaylor]

Is there any issue with placing some firewall items on the curved upper surface (above the rivet line)? I think the RDAC would be out of the way and easier to work on there. I've looked at the site topics and some builders sites trying to find a head-on photo of all the firewall items location (mockup) without the engine in the way. I plan the RDAC, grounding tree, air oil separator, master contactor, but only see the location of the coils, gas collator and volt regulator in the Aerovee installation manual.

Thanks,
Bud Taylor
Standard gear, single stick,
Aerovee w/o turbo

[Rynoth]

I mounted my RDAC and main fuse panel on that upper portion and it works just fine, here's a picture of a mockup of my firewall with the engine removed.



And a picture of those components mounted:



The locations in that mockup all ended up working with my Aerovee Turbo, here's a more finalized picture (you can see the RDAC, as well as location of my oil seperator.)



These pictures were taken from the following 3 posts on my blog:

http://www.rynoth.com/wordpress/waiex/2 ... ttery-box/
http://www.rynoth.com/wordpress/waiex/2 ... -mounting/
http://www.rynoth.com/wordpress/waiex/2 ... l-forward/

The only real concern is that you have enough space between the fuel tank and upper firewall for your nutplates/screws, and I found I had plenty of clearance for this.

[mike.smith]

Sadly I don't have a lot of photos of my firewall, but here are some. My battery is on the passenger side, and the smoke tank is on the pilot side.

http://www.mykitlog.com/users/display_l ... 01&row=164
http://www.mykitlog.com/users/display_l ... 53&row=135
http://www.mykitlog.com/users/display_l ... 56&row=563

For anything that goes on the upper firewall, keep a couple of things in mind:
1. There will be a fuel tank behind the firewall, which could interfere with the back side of some fastening hardware.
2. Because the upper firewall is impossible to get to on the back side once the fuel tank is in, make sure to use something like rivnuts to fasten your firewall forward hardware. Don't use anything with nuts on the back side in that location, that you won't be able to reach in the future.

[NWade]

As Mike points out, the biggest difficulty in mounting things high is the fuel tank making access impossible afterwards. Even with rivnuts or (preferably) nut-plates, you want to make sure any bolts/screws aren't too long or they're likely to be contacting the fuel tank and vibration of the airframe may cause them to gouge into the tank over time.

Here's how I mounted things up on my Firewall. I'm going to be challenged to fit the new Turbo cooling system in on the pilot's side of the engine mount, but otherwise I'm very pleased with the layout (which only works with a compact Lithium battery like the EarthX 680/680C):
https://flic.kr/p/VUjVqG

...it gets crowded once you add in all the necessary wires:
https://flic.kr/p/225t71b

Feel free to scroll through the album, there are many shots of the Engine & FWF in the first several pages:
https://www.flickr.com/photos/noel_wade ... 622771163/

--Noel

[kevinh]

Hi Noel,

Your picts look great. I also have been trying to figure out how to safety the airbox/intake. From your picts it looks like you have safety wire from the airbox to the engine mount. Are you sure that's a good idea? The reason I ask is won't the whole airbox assembly be vibrating wrt the engine, so safetying to the engine mount might be working against you. (I'm not really sure though)

[NWade]

The reason I ask is won't the whole airbox assembly be vibrating wrt the engine, so safetying to the engine mount might be working against you.

Kevin -

The Aeroinjector is affixed to a long intake tube, which itself is attached to the turbo with a silicone tube/sleeve. The long intake tube means that weight of the carb is on a long moment-arm, so without safety-wiring it to something solid the whole assembly will swing around quite dramatically! Secondly, there's enough flex in the silicone connectors to absorb any difference in the vibrations of the turbo and the wired/braced intake.

The safety wiring in this photo is the result of trying a couple of different arrangements and noting how much the assembly vibrated/moved during ground-runs: https://flic.kr/p/22QTC5C

NOTE: The edges/corners of the AeroInjector are quite sharp. They have sliced the silicone self-fusing tape I use as a protective material under the safety-wire. You may want to use a fine file to round & smooth the corners wherever you use silicone tape or rubber hose to protect the Aeroinjector from being damaged by the safety wire over time.

--Noel

[kevinh]

Thanks Noel!

[Rynoth]

The reason I ask is won't the whole airbox assembly be vibrating wrt the engine, so safetying to the engine mount might be working against you.

I did something similar to what Noel did but used a ~4" x 1/2" wide strip of aluminum sheet with a tab bent at both ends. I fixed one end to the top of one of the air filter bolts, and the other end to an adel clamp on the engine mount. The end result is fairly flexible and shouldn't impart too much in terms of vibration, but does maintain a positive force to keep all the intake connections intact. It's also very simple to remove when servicing the filter/carb.

[Sonerai13]

I did something similar to what Noel did but used a 3-4" x 1/2" wide strip of aluminum sheet with a tab bent at both ends. I fixed one end to the top of one of the air filter bolts, and the other end to an adel clamp on the engine mount. The end result is fairly flexible and shouldn't impart too much in terms of vibration, but does maintain a positive force to keep all the intake connections intact.

If you look at "Red One" you'll see a very similar setup. Adel clamp on the engine mount, and a short piece of aluminum going to one of the AeroInjector body bolts. Keeps things from coming apart while still having some flexibility.

[kevinh]

Thanks all! I'll do something approximately like the Red One plane.