Cabin Cover & Engine Choices

Cabin Cover

Section 43

It's the summer time, which means it's hot... excessively hot at times and there are several things that are practically miserable to do in the heat:

1. Eating soup
2. Going for a run



Fiberglass Battle Dress

3. Building a plane in the garage

When it's pushing 100 degrees outside even with an insulated garage and a fan it's still insanely hot.  I find myself grabbing rags and turning them into headbands, unconcerned that I previously used the rag to clean up Acetone.  On top of that my Fiberglass worksuit consists of an old Flight Suit from my sailor days, full goggles, gloves and and some sort of mask.  There's been times I've gone without this only to end up with fiberglass all over the place including my skin. So the unfavorable working conditions coupled with this summer being full of activities I feel like my progress has taken a bit of a hit.  I view it as a balance and as long as I continually make some level of progress then I'm good with it.

This brings me to what I've been working on lately.  I've been working on finishing up the wings control elements and wing tips in conjunction with the cabin fuselage.  Since I've made the most progress on the fuselage I'll write about that.  I decided to skip a number of sections and go to working on the cabin top fitting.  One reason is because there are some elements I'm undecided on for the interior that I want to think about it while I tackle these other things.  Another reason is this is a large piece that was sitting around and I wanted to do something with it.

I've heard there's a lot of angst with the cabin top and while it's not the most enjoyable part to deal with, knowing it's fiberglass and you can always fix it later helps out.  First part you do is trace the scribe lines and then go back and double check the scribe lines because they're not that accurate.

Pre-trimmed piece

 I choice to do the cutting in the driveway using disc grinder and then finished it off a bit with a disc rotary sander using 60 grit pads.  All in all I had to test fit it at least 10 times before I was happy with it and then another 2 times after that because I had overlooked parts.

First Trim

Closed that gap about another 1/16th of an inch.. rest will get glassed over

Once I was happy with my fit I pulled it off one more time to square up the edges per the plans and make sure nothing looked to wonky before I started the drilling.  I was happy to get back to drilling and really this part while a bit time consuming was enjoyable.  You basically put your forward tail skin on and use it as a guide to match drill #30 holes.  I broke all my smaller bits so used a 12" #30 to do this part.  You end up drilling a few, removing clecos and spraying out any material trapped between the skin and cabin top, then recleco and move on.

Action shot!

The step of centering the front brace with the fuselage top was a lot harder than I had anticipated. I tried several methods to center it taking various measurements clamping it in place stepping back, looking at it.. rinse repeat.  In the end it's centered as well as it can be, not sure what other people used but the best method for me was to center a large measuring stick across the front and then center the bar on that.  I'm happy with hot it looks.

So I'm now complete with this section for now.  The rest of the section involves trimming and placing the windshield and rear side windows.  Physically attaching the top along with all the fiber glass work which has to occur.  Because I will be removing the top for the interior, avionics, center channel ect this will end up being one of the last things I do before moving this all to the airport.

Now, it looks like a plane

Barrett Precision Engines

BPE is a shop out in Tulsa that overhauls a variety of aviation engine types for both the Certified and Experimental market.  I happened to be in Tulsa for work and took some time to check out their facility.  Monty and Allen were great and really helpful in showing me around and answering any questions I had.

When I first started looking into engines my kneejerk reaction was to get a brand new Lycoming 540 from Vans and install that.  I had called Rhonda at BPE and she did a good job explaining the differences between buying a new Lycoming vs an overhauled engine.  Essentially the pricing is relatively the same but the big difference is going through BPE you can be very specific on what you want with and done to the engine.  There's some features you can get on an overhauled engine that you can't really get on a Lycoming until after the fact and at that point you'll have some extra parts to sell and some extra costs in having a set of new Bendix magnetos for example installed.

My take away from the trip is I am aiming for a Lycoming 540 with 9:1 compression and most likely their cold air induction system.  The cold air induction system replaces the bottom oil sump pan with another one that has the air intakes on the outside, meaning the hot oil isn't heating up the air going into the engine.  This will make the bottom part of the engine hanging down lower than the standard engine, meaning unless I really want to do a lot of fiberglass work I'll have to get an aftermarket cowl from Show Planes. 

Another option if I decide the cost increase vs performance isn't there then I'll end up getting the same engine without the cold air induction system.  It's still a phenomenal engine but then I can get Rod Bowers ram air kit for both increased performance. An added value to this option is the easier lower cowl removal.  You end up taking the fiberglass cowling piece around the kit off and then the bottom cowling can move out without hitting your 3 blade prop.

Still have plenty of time to make some of those final decisions but bottom line is I'm getting the engine from BPE.