FT Speedwing control throws

AMMO193

New member
Good day folks,
Just fancied sharing my take on a very, very old FT design originally made by Chad Kapper himself. Lo and behold the ancient FT Speedwing (100mph for under 100bucks challenge).

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So as you can see some modifications... Scaled down by 5% (wingspan 25.5 inch instead of original 27.25 span) and some extra stabilisers.

Planning to run via 3 or 4 cell with 2200kv motor with 6x4 inch prop depending how I balance it... However I need to know what throws I need since flitetest didn't cover this in their article... I know I'm going very far down memory lane by trying to uncover this primordial design but if anyone that tried this before can help me determine the throw angles for the control surfaces or if there's a specific rule of thumb to determine throws for various rc wing designs. Much appreciated and thanks for the read!
 

Piotrsko

Master member
Since I have no concept on how big it is, I would start with not more than +/- 15 degrees and use a gob of expo biased for center. Better if your system can alter expo on the run. You could hang it on a string at the CG in front of a running box fan and see how twitchy that is, adjust accordingly. My KFM uses about +/- 10 degrees and will do all sorts of abrupt jinks and twitches flying slow, but probably has more aileron surface than wing area you have
 
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Bricks

Master member
Me personally would set up 2-3 fight modes with varying expo and throws if your transmitter will allow.
 

AMMO193

New member
Many thanks for the input!
So basically 12-15 degrees with 25% expo should be a good start?
My tx has dual rates (dx 7) and it can also be programmed to mix a bit of r-aileron along with throttle to counter torque roll which has been the bane of most of my maiden flights 😅
 

L Edge

Master member
1) For your maiden flight, if you have a lot of giddyap and go, launch at 3/4 throttle or so.
2) Think you will need some reflex, so put say 2 degrees of up elevator, with CG in center range.
3) Roll rate will be super fast, go to 1/2 throttle when doing your general trim. Then explore what happens to see if CG needs moving or thrust angle for level and straight flight.

Based on these two:

This one needs 2 degrees up elevator. Excellent speed due to no vertical rudders and to me, that is idle speed.. Never explored

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This one didn't need any reflex at all to fly and because drag and boundary flow is less, flies for 10+ minutes on a 1300mah battery for a 5 bladed 64mm EDF. Have videos for proof.
.

wing.JPG
 

AMMO193

New member
Very nice work, Edge! A dazzling display of colours you got there and are those meant to be kf steps at the front?
Happy flying!
 

Michael9865

Elite member
1) For your maiden flight, if you have a lot of giddyap and go, launch at 3/4 throttle or so.
2) Think you will need some reflex, so put say 2 degrees of up elevator, with CG in center range.
3) Roll rate will be super fast, go to 1/2 throttle when doing your general trim. Then explore what happens to see if CG needs moving or thrust angle for level and straight flight.

Based on these two:

This one needs 2 degrees up elevator. Excellent speed due to no vertical rudders and to me, that is idle speed.. Never explored

View attachment 247110

This one didn't need any reflex at all to fly and because drag and boundary flow is less, flies for 10+ minutes on a 1300mah battery for a 5 bladed 64mm EDF. Have videos for proof.
.

View attachment 247111

Is that about a 34” wing? Is it a kit or plans?
 

L Edge

Master member
Is that about a 34” wing? Is it a kit or plans?
My design. Plans were sketched on paper. It is 32" width and has a 8 x 3/8 prop. Not even explored what motor/prop to find top speed. I used FFF foam and designed it to fly in rough wind and turbulence going fast and slow.
Why not just try making your own and give it a shot. Reflex angle was 2 degree's. Try with end plates first.

 

Tench745

Master member
My design. Plans were sketched on paper. It is 32" width and has a 8 x 3/8 prop. Not even explored what motor/prop to find top speed. I used FFF foam and designed it to fly in rough wind and turbulence going fast and slow.
Why not just try making your own and give it a shot. Reflex angle was 2 degree's. Try with end plates first.

Just an FYI, embedded playback is turned off for that video, so we can't watch it here on the forum. Plays fine on YouTube.
 

AMMO193

New member
Did you ever go full throttle?
Didn't even go over 40%... I was using 6x6 prop because I didn't have 6x4, so didn't want to risk overloading anything. Besides the esc I used was one of those crappy $2 esc that didn't have anything written on them... Even throttle calibration was a pain!
Will try a different setup soon, otherwise great first flight!
 

Mr Man

Elite member
Didn't even go over 40%... I was using 6x6 prop because I didn't have 6x4, so didn't want to risk overloading anything. Besides the esc I used was one of those crappy $2 esc that didn't have anything written on them... Even throttle calibration was a pain!
Will try a different setup soon, otherwise great first flight!
Nice!