I'm pretty confident my wings are stiffer than the prototype. During the load test I think theirs deflected 22 inches, Mine only went 10 inches with a higher load. I designed for a higher gross in case later on I figured out a way to put an electric motor on it. I used 4 of the .092x.220 carbon rods on top and bottom dropping off at the 1/4 marks.
I remember having a conversation with Mick at Wallaby last year and he was describing to me then how then one flapperon would reverse direction at the end of the travel. I didn't appreciate the significance of it then but I suspect he was dealing with the same issue. I'll be heading down there in 4 days and get the scoop from him then. I'll post here when I get a handle on it.

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From: Philip Lardner <This email address is being protected from spambots. You need JavaScript enabled to view it.>
To: This email address is being protected from spambots. You need JavaScript enabled to view it.
Sent: Saturday, December 22, 2012 9:01 AM
Subject: RE: [Carbondragonbuildersandpilots] Re: First Flight




Hi Rick,

I've just thought of a possible reason for the odd stick behaviour you described. If the wing spars are too flexable then the hinge-line of the flaperon may also be bending up slightly when the wing is loaded in flight. This would translate at the stick as a slight resistance to moving the flaperon as you try to overcome the hinge-line flex and could also explain the tendancy for the stick to 'want to' fall over the centre and move full-travel at either extreme of left-right stick.

If this is the case then it may be necessary to somehow stiffen the hinge-line on the rear spar. The original rear spar design looks like it is more or less just a framework covered in cloth. I was actually planning to build a rear-spar similar to the main spar and use carbon rods and a single layer of CF cloth for the web. Now I'm wondering if this will be stiff enough! On the plus side, my flaperons will be split/rejoined at Rib #5, so that should prevent any excessive spar-flex from causing the hinges to 'bind'.

How many rods did you use in each spar, and how far out did you run them? You've got me worried now!

Just a thought.

Phil.

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From: This email address is being protected from spambots. You need JavaScript enabled to view it. [This email address is being protected from spambots. You need JavaScript enabled to view it.] On Behalf Of Rick Mullins
Sent: 21 December 2012 22:48
To: This email address is being protected from spambots. You need JavaScript enabled to view it.
Subject: Re: [Carbondragonbuildersandpilots] Re: First Flight



Thanks Dan. I knew you had flown the prototype and was hoping you would chime in here. I really appreciate the feedback. Control stops will be the next step. I can't see anything else that could be causing it.


I still need to do a little work on the brake. I don't have quite the clearance I need for the handle and when I tried to pull on full deflection I couldn't quite get it to the latch position. And like you said, it was starting to put up some significant resistance to going that far.

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From: Daniel <This email address is being protected from spambots. You need JavaScript enabled to view it.>
To: This email address is being protected from spambots. You need JavaScript enabled to view it.
Sent: Friday, December 21, 2012 9:42 AM
Subject: [Carbondragonbuildersandpilots] Re: First Flight




Rick,

Congratulations on your outstanding achievement! Your Carbon Dragon looks beautiful and ought to give you lots of good flying.

I flew the prototype during the testing program and did not notice the aileron non-linearity that you pointed out. You may want to set some control stops to reduce the maximum deflection a little. Since you mentioned that the down going aileron starts to go back up, your maximum control power will occur at less than maximum control deflection.

I noticed that your spoiler only deflected about 15 or 20 degrees during the approach to landing. Can you deflect it more than that? I noticed that the spoiler was not very effective at low deflections. I think the prototype would deflect about 35 degrees. Also, the forces on the control lever went up pretty high near maximum deflection.

Your landing looked a little long, but very smooth. Great job! Best of luck at Wallaby.

Dan Armstrong