FT Spear - with a drag rudders & speed brake

[dap35]

I'm mostly done with the build, just need to add the last wing tip/rudder, electronics, and balance. I have not flown a wing before, but decided to add drag rudders, so I modified the existing ones and extended them to make split rudders. I also figured out how to get the Aura programmed to limit the servo on each side so that it only opens up.

 

[Timmy]

I'm mostly done with the build, just need to add the last wing tip/rudder, electronics, and balance. I have not flown a wing before, but decided to add drag rudders, so I modified the existing ones and extended them to make split rudders. I also figured out how to get the Aura programmed to limit the servo on each side so that it only opens up.

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Interesting! I'm interested to see how quickly it slows down.

 

[Monte.C]

I'm mostly done with the build, just need to add the last wing tip/rudder, electronics, and balance. I have not flown a wing before, but decided to add drag rudders, so I modified the existing ones and extended them to make split rudders. I also figured out how to get the Aura programmed to limit the servo on each side so that it only opens up.

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Wow - Hey that's some high level RC engineering right there. Killer.

 

[dap35]

I maidened on Monday. It took two 3S 2200 batteries to get the CG right, but with the extended winglets, I am not surprised.
Windy day, but It flew pretty good and the drag rudders worked well.


One challenge I see is that with the winglets placed per the plans, it makes hand launching a bit challenging. I am thinking of cutting them back to be flush with the leading edge. Do you all think that will impact the flight characteristics much?

 

[dap35]

I got some help programming a mix into the Aura 5, so now I have a functional speed brake using the drag rudders.

 

[LitterBug]

NICE! Before I watched the video, I thought you were splitting the Elevons. Might be a cool progression.

 

[Merv]

Well done, great looking plane.

 

[dap35]

Thanks! I flew again today. I had changed to an APC 9x6 prop, still running on a 3Sx2200.
We had storms coming through so it was pretty windy and gusting. Nerve wracking!
Before I went out, I performed some minor surgery to trim the winglets back to match the leading edge. This made the launch less awkward and I don't think it changed the handling. At some point, I am going to redesign the winglets to extend back and allow for a larger rudder segment. Currently the rudder surface is about 2 inches. I would like more rudder authority.

 

[dap35]

This morning, I removed the in-board surface of the winglets and extended the rudder surface to 4 inches long. So the drag rudders are no longer split.

Way more responsive.

 

[2jujube7]

@dap35 How well do the speed brakes work? You mentioned in the video that you havn't tried them yet.

 

[dap35]

@dap35 How well do the speed brakes work? You mentioned in the video that you havn't tried them yet.[/QUOTE
I went out and tested the simplified version Tuesday. No flight video, I'm going to have to get a GoPro or something so I can capture these things.

No hard measurement on the speed brake, but I think they work fairly well. The rudder authority is vastly improved. Enough so that I cut of the test modifications I made and remade them. You can see the test I cut off on the table