SonexBuilders.net

I'm looking for recommendations on how to finish off the area between the two angles on the sidewall. In my case (at 6'-2 with a lowered seat), the forward angle really digs into my knee that lands on the edge of the front 1" angle. I want to create a flat surface between the two angles to give my knee a larger surface area to rest on. Possibly covered with some upholstery/ thin padding.
I'm thinking about a hinged panel off the top of the spar box, and creating a map/ pencil/ phone holder area. The picture below shows a white cardboard mockup of what I'm thinking. The top tab would have a fastener on the front angle (where the horizontal blue marker line is on the 1" angle), and it would be hinged on the 3 1/2" bottom leg to the top of the spar box. I'd probably add some foam to the bottom of the enclosed space to keep the depth manageable for storage of a cell phone.

I've got a swing back canopy arm that's going to restrict the use of a upholstered sidewall panel behind this area, but it doesn't go that far forward.

What did you do to finish off this area, and would you do it again the same way?

Thanks ahead for the advise!

Gregg Short
Burbank, OH
Sonex-A N715SX (reserved)

I wouldn’t recommend drilling any additional holes into that angle piece. It carries and distributes the full load of the aircraft in flight since it’s what the wing bolts to. Consider using Velcro or some other attachment method.

I left mine unfinished, mostly due to my religion of "weight is the enemy". I'm not afflicted by height like you are, but I've not found it uncomfortable. I have velcro on the right side to mount the little display for my fuel tank camera, and the angles protect it.

I sit in the middle (seat) which give me lots of leg/knee room.

With your picture.... my first thought would be.... you will drop something down there, and need it.

Tony,

Yeah, that's a concern..partly why I would make it hinged. But my thought was to use some tight fitting foam in the bottom to shorten the length, so it was reachable in the air. That seems easier and lighter than making a bottom higher up.
I am conscience of the weight issues here, but it really hits my knee in a bad space and the larger surface makes a big difference..so I'm doing something...even it it doesn't make storage space...But I'm ideally going for both.

As a retired Engineer, I'm not so sure how I see that angle carries 'the full load of the aircraft'. A few more 1/8inch holes are NOT going to make the wings spontaneously fly off or fold up. Neither will it make the upper longerons or canopy suddenly depart the rest of the airplane. For non-structural places I may want to get to in the future, I use hardware store aluminum pulled rivets. They are super easy to drill out and replace. You can almost do it as fast as a screwdriver ;) Your little leg guard will be just fine.

I agree with an earlier comment about using velcro. Creating a simple flat panel with flanges that fit over/span the vertical angles, but fits with a bit of tension (with space for velcro). Tension, such that you'd have to flex the flanges out a bit to get the panel to fit. Easy peasy, and you don't even have to think about if you are drilling holes where you shouldn't ... even if you agree that it will not affect anything.

For what it's worth........while rigging the wings last week, holes that were factory pre-drilled in the forward vertical angles and forward tunnel Z, that were intended to be the pilot holes for the wing attach pins, fell outside the actual pin location. This left a .040in hole that overlapped the 3/8in pin hole.

A query to Sonex tech came back as a "do not use".

Replacements will be installed. No small task.

Drill holes in the verticals at your own risk. .

That’s no fun. I had to remove rivets in one of my verticals but wasn’t as far as you. I marked the F16-02 tunnel z with do not drill this hole on both sides right away when I found the note with an image on the drawing revisions page here: https://www.sonexaircraft.com/files/plan-sheets/F16-02-Errant-Hole.jpg