Page 1 of 2

SuperSTOL Flap Handle

PostPosted: Mon Oct 06, 2014 11:52 am
by kenryan
Can anyone flying the SuperSTOL tell me if the handle could be reasonably shortened? Is all that leverage really necessary?

Re: SuperSTOL Flap Handle

PostPosted: Mon Oct 06, 2014 4:26 pm
by accent air
Yes you need it all. Not a good idea to shorten

Re: SuperSTOL Flap Handle

PostPosted: Tue Oct 07, 2014 4:27 am
by Just Aircraft NZ Ltd
Yes, you certainly do need all that leverage. Those are big flap surfaces to pull down against the airflow.

We have found that you can engage the first knotch at about 50 mph but it is impossible to engage knotches 2 and 3 until the airspeed is right back and the slats are well out.

Part of the issue is that pulling the flaps on ( 2 and 3) if the airspeed is too high causes the flap handle to deform, binding up the inner locking tube. So, although the flaps can be deployed, the force required is too much for the handle, at speeds above 40 or so and they will not lock down.

Then to have to ease them off again and manage the attitude change all while slow and low can be a bit of a handful.

It's not necessarily a bad thing tho', as we know what can happen to big Fowler type flaps, hauled on at to high a speed.

I do think we will put some work into beefing up the lever a bit as it happens in the white arc.

How do you find yours John Levyland ??

Cheers.

Re: SuperSTOL Flap Handle

PostPosted: Tue Oct 07, 2014 3:20 pm
by taildrgfun
I agree, DO NOT shorten it. I cut the inside tube and make it a smaller diameter all except for the ends to reduce binding when the outer tube flexes. I wish the factory would make the outer tube a little heavier wall to reduce flexing and binding.

Re: SuperSTOL Flap Handle

PostPosted: Tue Oct 07, 2014 7:19 pm
by kenryan
Thanks guys. You've given me some things to think about. The whole mechanism seems vulnerable.

Re: SuperSTOL Flap Handle

PostPosted: Tue Oct 07, 2014 10:04 pm
by danerazz
You could put a gas spring on the short end to reduce the forces, but the index plates would need positive notches to avoid the flaps auto-deploying on the ground/low speeds.

Re: SuperSTOL Flap Handle

PostPosted: Tue Oct 07, 2014 10:06 pm
by danerazz
Then again that would counter the return springs, so you would have to "push" the flaps up. The return springs would just keep tension on the cables.

Re: SuperSTOL Flap Handle

PostPosted: Tue Oct 07, 2014 10:11 pm
by danerazz
Now that I am thinking about it, if you attached the gas spring to a bracket that was over-center on the handle, you could control the ratio and have it push down harder as you extend the flaps, and as they get close to up it would push the handle down (flaps up). If you played with it you could probably get the ratio to basically cancel the forces on the handle since the aerodynamic forces increase with extension. It wouldn't be perfect because of varying forces at different airspeeds, but I bet you could get it close.

Re: SuperSTOL Flap Handle

PostPosted: Sun Oct 26, 2014 1:22 pm
by levyland
Yes you need every inch of it and then some. Also I don't know if you got the replacement part from the factory but because there is so much pressure on the outside metal tube, Troy made a new part that has the button on the top and then a 1/4" steel tube welded to that and then runs down to where the locking mechanism is. I could not get my flaps down to 40 degrees without the airplane flying super slow. Cheers John

Re: SuperSTOL Flap Handle

PostPosted: Thu Feb 12, 2015 4:40 am
by R Rinker
Thought I'd mention my work on the flap control. I realized it would be critical for the retention bolt to seat perfectly in both plates or it would slip out easily, but drilling the hole through the button sleeve would be hard to do with the precision for this to happen. What I did was bolt the assembly together in place on the airplane, then take the assembly out and shimmed and clamped it up on the drill press so that the bit seated perfectly in the place where the retention pin goes in one of the notches.

Then I moved the handle down and drilled through the slot. If nothing moved this should assure the pin would seat perfectly in the notches. It worked very well.

I also dressed out the notches in the plates so the pin would seat better...being very careful not to touch the points. I used blueing to mark the points so I could make sure I didn't touch them.

The next issue I think may be causing others some trouble. The slot in the handle was too small for the pin bolt to fit in and I had to file it out a little. The pin kept sticking very badly, so I rolled the edges of the long handle slot so the pin wouldn't touch the sharp edges but ride on the middle. When I did this it had a dramatic effect of the smoothness of the action and the assembly functions with a very positive feel. If this isn't done it would be hard, in actual use, for the pin to even get seated.

I'm wondering how many cycles this assembly will be good for in actual use before the points of those notches wear off. When I get it flying, and if it works well in actual use, I guess I could experiment lubing it..and if that causes it to slip out I could always clean it off and go back to dry. I have pictures of all this if anyone wants it.

Re: SuperSTOL Flap Handle

PostPosted: Thu Feb 12, 2015 9:35 am
by SheepdogRD
I'd sure like to see those pictures, Rodger.

Re: SuperSTOL Flap Handle

PostPosted: Thu Feb 12, 2015 1:15 pm
by kenryan
I'd like to see the pictures too, Roger.

What I did was replace the spring in the handle with one that is considerably stronger. My mechanism seems to be working pretty good. Of course, being as long as it is, it seems quite vulnerable to side loading. Hopefully in normal use it will be easy to pull straight back.

I am going to do three other things as well: 1) like Steve Henry, I'm going to cut off the ends of the inner tube (about 3 inches) and connect them with a smaller diameter tube. 2) also on Steve Henry's advice I am going to add a small plate to the "button" so that if there is any binding, at least there is something grab and pull 3) add a "spine" to the bottom of the tube, hopefully making it stiff enough so that it doesn't flex (and bind)

And then, it seems that stronger flap return springs are needed, so when I get to rigging I will look at that as well.

Re: SuperSTOL Flap Handle

PostPosted: Thu Feb 12, 2015 4:22 pm
by R Rinker
The first picture shows getting the assembly clamped and shimmed so the bit rests in the notches. The assembly has to be bolted together on the airplane first and enough bolts left in to hold it well.
Image
In the next picture the handle is moved into place and drilled through. Make sure nothing changes position in the clamps when moving the handle.
Image
The next shows the notches dressed out with the blueing showing the points were not disturbed. I used a 7/32 chainsaw file which is for .404 chain because it is a little smaller than the pin and doing it by hand it comes out just right. This has to be done very carefully and may not be possible unless you've spent your life sharpening chain by hand without a guide.
Image
The next shows enlarging the slot. I had to do this because it wasn't big enough for the pin bolt to go through. The important thing is that you have to roll those edges, both inside and outside, then hone them real smooth with a steel or it will stick real bad.
Image

Re: SuperSTOL Flap Handle

PostPosted: Thu Feb 12, 2015 8:47 pm
by R Rinker
After reading others are having trouble with the position pin sticking and looking at the pictures, I realize the edge of the pin bearing surface of the plates need to be slightly rolled, just a few thousands and honed with a steel. After seeing how this improved the pin action moving up and down in the handle I think it will improve the pin movement in the plates also...looking at a picture like this is better than holding it in your hand and looking at it.
Image

Re: SuperSTOL Flap Handle

PostPosted: Thu Feb 12, 2015 10:57 pm
by User GDS
I did all of the suggested improvements to the mechanism to make it operate smoothly and finally got it to work well. definitely put something on top of the button. I drilled into the top and bonded some all-thread rod, then screwed on a plastic knob with a threaded insert. When I'm coming into a tight spot I pull up on that knob to insure the bolt is engaged. Even though I've got it working well, if I'm a little fast (pulling a lot of tension on the cables) in full flaps, if my forearm touches the button while I'm operating the throttle they'll pop out of the 3rd notch. And the only lubrication I use is molybdenum disulfide, a dry lube. spray silicone might work OK too, just avoid anything that gets gummy