Pre-Fitting Your Wings

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Check For Problems First

Problems with the kit "may" occur, which is the primary reason each Challenger builder should do a pre-fit of the wings prior to covering. In our builder's case, a problem was discovered prior to covering, and during pre-fit. The inboard spar on one wing was drilled for the Rony bracket at an angle. If unnoticed prior to covering, our builder would have been out covering materials, paint and a whole lot of time. He contacted QC with the problem and the factory immediately replaced the wing, which individually cost about $700.00 each, if bought separately. This really says a lot for the integrity and support Quad City offers following a kit sale.

Wing Pre-Fit

Find a helper to assist you during the prefit. Have a temporary stand available, such as a step ladder, on which you can rest the outboard end of the wing. The fitting process can take some time and anyone trying to hold up the outboard end of the wing will get very tired.

Secure the inboard ends of the wing spars to the Rony brackets at the root tube and prop the outboard end of the wing up on the stand. Slightly loosen each strut bracket on the wing spar, and slightly loosen each Rony bracket on the fuselage longeron.

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Attach the upper end of the lift strut to the bracket on the wing spar with the bolt, but don't fully tighten it down just yet.

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Swing the lower end of the lift strut into position in the lower Rony bracket. Your helper will probably have to raise or lower the outboard wing tip while you fit the lower end of the strut into the Rony. You will be able to see if the lower end of the strut is close to being in alignment with the Rony.

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If the lower end needs to be pulled more than 1" in order to get it to align with the Rony then you will need to find out why the alignment is so far off. It's not a good idea to force the strut into alignment if that will create a noticeable bend in the strut itself. Correct the alignment problem.

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Here are some things that could cause a misalignment of a strut to a Rony bracket.

  1. Check that the Rony bracket holes and their locations along the longerons are the same right side compared to the left side.

  2. Check that the hole in the upper end of the lift strut was drilled at exactly 90 degrees to the strut.

  3. Remove the two flat strut brackets from the wing spar, lay them on top of each other, and make sure all three holes line up exactly.

  4. Check that the two holes drilled in the wing spar are exactly 90 degrees to the spar.

We also recommend you check our article on "Correcting Turning Tendencies", by Bud Connolly, section #3. "Correcting Washout or Wing Warp".

After installing the lift struts to both wings you can now tighten all the bolts at the Rony brackets and wing spar brackets.

You can also now finish making the aileron pushrods and install them. If you have the flaperon mixer, make sure it is set in the neutral position before fitting the pushrods. The total travel of the mixer crank should be about 20 turns. Crank the mixer full forward, then back it off 8 turns to the rear. This allows 8 turns of up trim and 12 turns of down trim, which is considered the neutral position.

Now, onto covering your plane! :-)