Official Skynetic Bison XT STOL Discussion Thread

[2much2do]

Maiden today + 3. Getting used to how it flies. Great for doing touch and gos. As previously been reported you have to keep power on it but i like the way it flies. Got the tailwheel to mostly turn left using tighter springs and 125% rudder but i think i will try a closer hole for more travel. Has anyone come up with any ideas for the red hot light controller? I originally had it switching on and off on the gear channel but that stopped working (fried?) Now they're on all the time. Using 6s 5000 at 70 mm seems like a sweet cg. Landing with about 45-50% after 8 mins.

I know the LEDs will run off of 5V, but has anyone tested to see of the controller will? If that is that case, then putting it after a higher current BEC might be a good option.

[2much2do]

For those keeping score, the light controller is scary hot on a 6s Pack, (I know we knew this but I'm adding too it so that motion will maybe see and fix this for us).

That being said, I ran 6V from a cheapo hobbyking BEC I had in my stash and the light work great, without any issues of heating on that board. So that's the easy answer even if it should not be the case.

I also split out both the ailerons and flaps so that I can precisely use individual channels, I'm keen to try aileron droops (camber), since that should work if the slats are working, and maybe slow down controllable flight.

[wperry38]

witch prop is the 6S
bp

[2much2do]

witch prop is the 6S
bp

15x8

[Starck Mad]

So this is interesting...In was just about to do the mod on my tail wheel and I thought of something, and then noticed something else. I thought about twisting the springs a half turn on one end when hooking them up instead of hooking them up straight in line. This added some tension. While I was messing with it I noticed for the first time...as this was the first time I moved the tail wheel right and left by hand...that there was a great amount of friction and it was a bit hard to move. It was also harder to move to the left than the right. Hmm. So I noticed the horn was tight down on the assembly and there was enough flat spot on the tail wheel wire for the grub screw to raise it up a bit and get it off there where it was rubbing. I did that and put 3 drops of hobby oil down the channel the wire moves in and the combination of all this has resulted in having more tail wheel throw than I've had yet...and at least on the bench it seems like more than enough. Taking it flying this afternoon...we will see. And so will all of you...update video coming first of the week.

Man if that turns out to be all it was for mine I'm gonna feel like a dope for not checking that way before...

[skiervh]

So this is interesting...In was just about to do the mod on my tail wheel and I thought of something, and then noticed something else. I thought about twisting the springs a half turn on one end when hooking them up instead of hooking them up straight in line. This added some tension. While I was messing with it I noticed for the first time...as this was the first time I moved the tail wheel right and left by hand...that there was a great amount of friction and it was a bit hard to move. It was also harder to move to the left than the right. Hmm. So I noticed the horn was tight down on the assembly and there was enough flat spot on the tail wheel wire for the grub screw to raise it up a bit and get it off there where it was rubbing. I did that and put 3 drops of hobby oil down the channel the wire moves in and the combination of all this has resulted in having more tail wheel throw than I've had yet...and at least on the bench it seems like more than enough. Taking it flying this afternoon...we will see. And so will all of you...update video coming first of the week.

Man if that turns out to be all it was for mine I'm gonna feel like a dope for not checking that way before...

I noticed this as well. Where the rod bends and goes through the nut....on the inside part of that 90 degree bend is where there's a lot of friction, keeping the rod from rotating more freely. I'm still unsure how to remedy this.

[Starck Mad]

I noticed this as well. Where the rod bends and goes through the nut....on the inside part of that 90 degree bend is where there's a lot of friction, keeping the rod from rotating more freely. I'm still unsure how to remedy this.

Actually on mine the friction was because of the control horn on the top of the assembly. When i raised this up just a hair...and oiled everything...free and easy.

[Starck Mad]

Well...that was it. My Bison turns well either way now...on the Geo textile or on grass. So...at least for mine...turns out nothing was wrong with my tail wheel springs. I'd like to think moving the control horn made the difference, but to be truthful I think it was as simple as doing something we all have to do to maintain any model...oil it where it needs it. I have video showing the results. We will post our update video first of the week with this information as well as the corresponding footage among other findings and footage flying it like we haven't before... performance on 6s AND 4s. I hope this fixes the tail wheel issue for everybody else as well...doesn't get much easier than that!

[Atrix]

Well, I did this and it was crazy successful in terms of tightening up ground steering authority. I was able to drive the Bison like an RC car around my small front yard including laps around a tree. I have no idea how risky this is for the rudder servo. Perhaps I should put a servo saver horn on it.

[skiervh]

Curious as to where some of you mount your battery in relation to CG. Manual says cg is 57mm aft of leading edge. If I center my battery on that and mount on the lower level of the cockpit, this seems to render those stock battery straps useless as they are too far forward. Are some of you mounting on the upper level of the cockpit to match cg that far back?

[2much2do]

53 is way forward unfortuantely, so some of the preceding posts and videos. Although im not sure what your setuo is, im getting about 75 mm with a 4000mah 6s at the very back of thr lower tray.

[skiervh]

53 is way forward unfortuantely, so some of the preceding posts and videos. Although im not sure what your setuo is, im getting about 75 mm with a 4000mah 6s at the very back of thr lower tray.

Actually it says 57, typo on my original post...either way I thought it was too far forward regardless.

So running your battery further back, are you able to get a strap around it or are you just using vecro?

[2much2do]

Im barely able to use both strap. I might hunt up a piece of neoprene to put in there to prevent any sliding.

[Gilatrout]

Well, I had some time to work on Bison, but I too have the backwards strut assembly problem and so until that is resolved it's grounded.


Thanks for the advice on the tail wheel. A little lubrication, and some fiddling it is much better. Still not where I want it, but not a blocker anymore.

Damn this model has been frustrating.

Oh one more thing, check the glue for your flap and aileron control horns. One of mine wasn't glued properly.

[Remberin3]

Just got mine today. I noticed that the windows look like they have overspray on them and the very top one looks like someone dropped CA on it. Also there are not enough y harnesses to plug all the lights in. Also the esc was disconnected from the motor, and just laying loose in the battery tray.. Was anyone else's like this or did I get one that was returned by someone.

[2much2do]

I have been holding off on actually writing my review on their website until I had enough parts to actually fly it. It really bums me out the way so many of us are getting a bit hosed on this deal.

[Gilatrout]

I have been holding off on actually writing my review on their website until I had enough parts to actually fly it. It really bums me out the way so many of us are getting a bit hosed on this deal.

Well I'll put it this way. I will never ever buy another Skynetic branded plane right away even if it is one of the unicorns. Even then it is going to have to have amazing reviews for me to order it,

[2much2do]

Well I'll put it this way. I will never ever buy another Skynetic branded plane right away even if it is one of the unicorns. Even then it is going to have to have amazing reviews for me to order it,

I would agree, Motion had a great reputation as a re-seller but they are kinda failing as a manufacturer in my mind. And my experience was that their customer support regarding their own product is less than stellar.

They tried to make an item that was higher end than they were capable of producing, with features that were beyond the designer's understanding.

This might seem unfair, but the more I think about what they've done the more frustrated with them I become.

[Denc23@comcast.net]

Couple of videos I saw CG was 75-77mm from forward slats. Think I’ll start at about 70mm. I usually start at 30% of the cord, which should be the thickest part of wing or at the spar on normal wing.
Most all tail daggers have the tail wheel connected directly to the rudder, no springs, so shouldn’t hurt the servo removing the springs hand using straight linkages.??

[2much2do]

Couple of videos I saw CG was 75-77mm from forward slats. Think I’ll start at about 70mm. I usually start at 30% of the cord, which should be the thickest part of wing or at the spar on normal wing.
Most all tail daggers have the tail wheel connected directly to the rudder, no springs, so shouldn’t hurt the servo removing the springs hand using straight linkages.??

I, mean, depends on you. You put any shock into the plastic horns on the rudder. So if you always land gentle it would be fine. Im not sure how strong those horns are, if they are strong you will also be fine.