Part 12: Installing the L-angle stiffeners to the rear bottom wing skins

Now we install L-angle stiffeners to the rear bottom wing skins:

This is an easy job with the top rear skin removed. We trim the L-angle piece to length, pre-drill it, and then drill and cleco it into the bottom rear skin:

We'll share the position measurements and exact details with the final drawings. The Upgrade drawings are nearly finalized (which will allow us to then release and ship the Upgrade Package kit) and allow us to finish the upgrade on our Zodiac XL

Here's the video clip of us installing the L-angle stiffeners to the rear wing skins:

The CH 650 model already incorporates the L-angle stiffeners on the top rear skin. The CH 650 model also has diagonal L-angle stiffeners in the rear fuselage side skins.
Here's a view from inside a CH 650 fuselage under construction:

Note of Corrosion: As we've disassembled various sections of the factory demonstrator Zodiac XL to install the Upgrade Package, we've inspected for any signs of corrosion, and though it was built back in early 2001 this aircraft shows virtually no signs of corrosion anywhere. The 6061 T-6 aluminum alloy and the blind rivets have held up very well. The only signs of corrosion that could be found anywhere was minor surface oxidization on chrome-moly steel parts where the paint had rubbed off (on the rudder pedals).

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Comment by John Thompson on November 23, 2009 at 11:10pm
Sebastien: I look forward to and appreciate each installment Video of the upgrades. I have already began the disassembly of my beautiful bird and I should be ready for installation when the upgrade kit w/prints arrives.
Comment by Leroy L Pearl on November 23, 2009 at 4:38pm
Sebastien: I would like to see a joggle to loce the ribs in on the lbracket that would lock each section togather. I think that would be stronger.
Comment by Mark Hubelbank on November 23, 2009 at 4:06pm
Is there any way we can get on the list for the kit shipments? It is better to know that one is already on the waiting list than to wait for the announcement day.
Comment by Lance Gingell on November 23, 2009 at 9:49am
Hi Sebastien,
Since the wing L angles are not structural, may be it would be a good idea to bond them in place (if you supply enough of the other glue in the kit)...that would look much cleaner, less draggy and maybe quicker too...
What do you think?
Thanks for the great updates by the way..
Comment by Phill Barnes on November 23, 2009 at 3:15am
Hi Sebastien
How is the upgrade comming?
I would love to see some more blogs with videos.

Comment by Felipe Uribe Posada on November 22, 2009 at 9:47am
Hi, Sebastien,

This upgrading issue has me a bit concerned since I am the sole zodiac project builder in Colombia and I have to relay solely on the upcomings in the US, without having local experience to benefit from. I regret that according to my progress I was expecting to have the plane finished by january 2010, but I am sure this extra work is for the good of the aircraft and the experience of flying it. Please advise as to how to get the drawings and parts and when do you expect to be shipping the kit?

Regards, Felipe Uribe Bogotá, Colombia Zodiac 601 XL - 7004
Comment by Clarence K. Andrews on November 21, 2009 at 1:01pm
I am waiting to receive the mod kit before I start on the preparation for the installation. In the few hours I've flown my 601, my only complaint is the heaviness of the ailerons. I have the hingeless aileron attachment. If I change to the piano hinge, will this make the ailerons lighter to control? I have 450 hours in a Cassutt, so I am used to having light controls and don't think I'll have trouble over controlling with lighter forces required.
Comment by Sebastien Heintz on November 21, 2009 at 11:30am
I'll cover removal of the nose skin in more detail in a future post. We "upgraded" the first wing (right) with the noseskin still attached (on the bottom) and we completely removed the noseskin on the second wing (left). I think that we will recommend the latter since it's not additional work (to remove the noseskin) and makes it much easier to access the spar area for the upgrade.
Comment by Jake Reyna on November 21, 2009 at 7:05am
Sebastian, will the Upgrade Package include these additional stiffners for the wings and fuselage? I had already incorporated stiffners to the wing bottom skin on my XL, but had planned on waiting to do the rear fuselage until after I had done Weight & Balance. I'm using a Jabiru, wouldn't be an issue with a Corvair or O-200.

Regardless, this will be a great time to order additional L-angles, rivets, etc., you can't get this stuff at Home Depot.
Comment by Greg P Couttie on November 21, 2009 at 4:59am
I notice that you have completely removed the nose skin ,can you advise why you have done this?

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