NACA Inlet Installation


With the firewall installed, my next task was to install the NACA inlet.  The purpose of this installation is to bring air into the engine compartment for combustion and cooling.  The actual inlet came pre-formed in the original fuselage kit, so it was just a matter of cutting a hole in the bottom of the fuselage and bonding the inlet in place.  Pretty straight forward, really.  The cut is a little under-sized; I did that figuring that I could do a more precise job the next time I had the fuselage upside-down.  

I decided to cut the inlet hole through the firewall after the inlet was installed.  In hindsight, that was a mistake.  It would have been far easier to cut the plywood firewall first.  Oh well... lesson learned.

By the way, the circular "patches" you see in these photos are the engine mount reinforcement plies.  They're on both sides of the firewall.

As far as the builder's manual was concerned, as soon as I installed a glass ply over all inlet-to-firewall joints, I was done with the installation.  But I decided to take it a step further.  To stiffen the whole thing up a bit I installed some " foam core around the periphery of the inlet and capped it off with a single S2 glass ply.  This added about a pound to the airplane, but I think the installation came out a lot better.  The photo on the right shows the completed installation before I had removed the peel ply.

I guess that's about it for this chapter.

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