slkret123

I'm all finished building and painting / weathering a winter camouflage scheme on an ESM 80" Stuka ARF done as a G version with the big cannon under each wing. My question here is how to align the flaps and ailerons. The build manual is silent on the matter. I thought I read on a forum a while back that they should be aligned to be parallel to the underside of the wing but I can't find the reference anymore. There seems to be a little logic to doing it that way. But it also would seem that aligning them them parallel to the chord line of the airfoil would make sense. There are a few guys who have crashed on their maiden flight because the surfaces were not properly aligned but they don't mention what the right way is.

Is there anyone who knows by experience which way the surfaces should be aligned?

Thanks

Steve

Lifer

My Feedback: (1)

Incidence meter for the wing, and a small level on the surfaces would work.

slkret123

What you are proposing is that the control surfaces would be aligned with the airfoil chord line which was the second option I mentioned above. Is your recommendation based on experience with the ESM Stuka?

Steve

Lifer

My Feedback: (1)

No experience with the model, just a lot of time with aircraft design.

Propworn

My Feedback: (3)

I have no experience with an ESM Stuka but years ago I helped a good friend set up and maiden his Ziroli Stuka. I know it’s not the same plane but if it helps.

His wing was quite scale in the operation of the control surfaces. The flaps operated separate from the ailerons yet through mixing he could lower both.

Setup was neutral on the airfoil when raised and all surfaces were set identical. He played with fine tuning it in this configuration until it flew hands off.

The hardest was to have them lower equally throughout the range of movement. His first flight he used nothing but ailerons making sure he was 3 mistakes high before slowing it down so see where it might stall without flaps. He landed and we made adjustments to mechanically center the ailerons.

After several flights with no issues he began to lower the flaps at 3 mistakes high. They must be pretty effective because some where about half flap the airplane wanted to roll right. This was due to a slight miss alignment of the servo arm. Could not solve it mechanically so he replaced both flap and aileron servos with Hitec digitals (programmable). Now he could not only adjust the travel but speed as well. The speed part really helped when lowering everything. He also mixed some down elevator so the model did not change attitude with speed or throttle movement.

Next he set up the flaperons the same way and finally mixed the two to work in conjunction with each other.

Let me say my buddy is a bit anal when setting up his models. It took a good part of 2 months to get it to where he liked it. Every time he had a spotter/helper in case it turned into a handful and needed a third hand to return the switch to normal. He only changes one thing at a time and like a little white dog on a pant leg he doesn’t let go until he’s satisfied.

I can’t find fault with his method he fly’s the crap out of that thing and it’s like its on rails.

Good luck, take your time get it right it’s a great looking model in the air.

Dennis

slkret123

Propworn:
Thanks for the reply and the comparison to the Ziroli Stuka. What is not clear is your line that says "Setup was neutral on the airfoil when raised and all surfaces were set identical". Are you saying that the flaps and ailerons were aligned with the airfoil chord line or aligned with the bottom surface of the airfoil? Big difference.

Steve

Lifer

My Feedback: (1)

Chord line is what you seek. The two need to be parallel for neutral control.

Propworn

My Feedback: (3)

Bolted wing in place used an incidence meter zeroed out the wing (cord line) then went 0/0 on the control surfaces. He made a cradle to hold the whole aircraft in this position then installed and leveled the control surfaces. He made a small fixture for his inclinometer so it would sit on his horizontal stab and he just raised the tail until it zeroed out.

Dial Gauge Angle Finder Inclinometer Meter. Valkyrie NIP | eBay

Warns on the side of caution as the two airfoils may not be the same.

p3arljam

My Feedback: (5)

Can anyone measure the wheel pants i need the length , height , width and the size of the hole at the top of the wheel pant.

Thanks