Part 13: Removing the Wing Center Spar Section

Again, I want to thank Doug and Lori from Quality Sport Planes for organizing and hosting the free "Upgrade Workshop" this past weekend at their facility in Cloverdale, California (shown above). This was an excellent opportunity for Zodiac XL builders, owners, and pilots to learn about new upgrades, and how to install them. For more information, contact Quality Sport Planes at (707) 894-4084.

I haven't posted in a few days. This is not because we're not working on the Upgrade; in fact, it's because we've been working on it, and sometimes we've been reworking it!

The above photo shows a new Wing Root Doubler (6-ZU-1) that replaces the previous doubler. This new doubler is even "beefier" (.125-inch istead of .063-inch thick) and goes back 320 mm. (instead of 180 mm.). I'll be posting details and info on this shortly, and we'll post updated drawings as soon as we clean them up...

Those of you who are following and contributing to the Q&A - Safety Alert and SAIB - Zodiac XL / CH 650 discussion know about these ongoing changes as we finalize the drawings and the Upgrade Package kit. As Mathieu Heintz stated in a Q&A discussion, we've been sharing the Upgrade Package drawings with CAA (civil aviation authorities) officials and engineers around the world to obtain their suggestions and comments, which in turn has prompted additional changes. To everyone's benefit, we are finalizing the Upgrade Package drawings and kit before we start shipping so that everyone can benefit from them. (Again, this is a reminder that the draft drawings are indeed drafts: Wait for the final drawings before making and parts or starting to rivet parts together).

Removing the Wing Center Spar Section:
Below, we start to remove the center spar assembly from the fuselage so that we can upgrade ("beef up") the center spar:

On our demonstrator aircraft. most of the wires were routed through the control column torque tube (6B17-4) so this was a little more work than originally anticipated.

Roger drilled and then tapped the rivets out of the bottom of the fuselage.
We drilled out the center spar assembly, including the forward Wing Attachment Uprights (6B13-1):

Roger lifts the center spar assembly out of the fuselage.

Steve inspects the center spar section before we start disassembling it.

Here's the video clip:

Next, we'll disassemble the Wing Center Spar Section.

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Comment by Bob Archibald on November 25, 2009 at 3:31am
The open manner in which the Heintz family is carrying out this modification program testifies to their character.
They have nothing to hide and only the best interests of their customers. Thanks Chris, Michael, Mathieu, Sebastian and Nickolas.
Cheers, Bob Archibald
Comment by Scott Thatcher on November 24, 2009 at 9:04am
I noticed that the wheel pants were removed from the main gear. Was that for access? Also wanted to mention that the videos are an extreme help in viewing how the entire process is done. Thanks for such an open presentation.

Now I need to lose weight just to be able to lean over the longerons!
Comment by Matt Archer on November 24, 2009 at 8:01am
Tips. I have kept a photo log and web page. Before you start tearing into your wiring. Make sure you document and photo what goes where. This is going to take a little longer than I thought


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