[cptkirk]

Wonder if anyone has any input regarding the Sopwith Camel wing incidences

What I am showing on this ARF is

Bottom wing at zero degrees using Robart meter. Top wing is at minus 2.5 degrees and horizontal stab at minus 2.5 degrees. The plane was flown by an expert pilot and it has a tendency to dive. Hangar 9 hasn't been much help.

Thanks for your collective wisdom.

[williame3590]

Bottom wing at 0, stab at 0 and top wing at +1

Bill

[cptkirk]

Thanks......................struts and cabanes on this ARF are 1/8" difference and not labelled in the kit. Reading online of a few others with this ARF having issues with the same thing. Plane wasn't assembled by me and it was generally beautifully done, just trying to improve it's flight characteristics.

Not trying to be critical of the person who assembled it as this ARF is a difficult bit of kit to assemble in the first instance as witnessed by some build threads online. Critical parts were not labelled to start with. Hangar 9 / Horizon usual good support in this case has fallen down in this case with no replies.
Their support bulletin posted on their site regarding this ARF is little help.

Here is a video of the plane flying now at the quoted minus incidences with an expert pilot.

You Tube

You Tube

[cptkirk]

The other thing I have noticed with this ARF is that with the lower and upper wing aileron linkage provided there is an issue setting up aileron differential.

With the lower wing set at 1"throw recommended up and down on the lower wing the upper wing linkage gives an up of a little over 1/2 inch and down of 1 inch.

There are no adjustments that give equal travel of the upper and lower ailerons so that differential can be mixed into the travel.

Anyone noticed this before? I am using ruder mix of 30% to compensate. Conversley with no mix adding rudder in turns is my normal flying habit.

[Flypaper]

I don't know what they use for hinges for that particular plane, but the hinge point must be in the centre of the ail. trailing edge for both ails., at least on the same point on each ail.in order to get the same throw. Differential can then be programmed with the trans. using the servo end points.Some use a hinge point on the bottom ail. above the ail surface, and the bottom of the upper ail surface. This is a big no,no. and will give the different throws that you mention.

Gord.

[cptkirk]

Interesting that Hangar 9 put the bottom attachment point for aileron to aileron linkage in the MIDDLE of the upper surface of the lower aileron and the upper linkage attachment point on the underside at the TRAILING edge of the upper aileron.

The attachment points are light ply glued into the ailerons with a hole drilled in each for the link.

[Flypaper]

The pivot point has to be in the centre of both ail. trailing edges to get equal travel. Best is to have ail. servos on separate channels so you can set the servo endpoint separately.Best differential is twice as much up as down for a place to start. What radio do you have??

[cptkirk]

Using Jr Xp9303.

[leopard1]

What motor do you have in your Camel? CoG is very touchy on this plane

[cptkirk]

OS 70 Surpass 4 stroke with 14 x 4 APC prop. Have a laminated 14" wood prop for static display.

Picture of the aileron linkage. Shows what I'm talking about re differential geometry.

This is a picture taken from a build thread online and is not the plane I have but mine has the exact same geometry and anchor points. I had a look at the manual and a closer look at the ailerons.

There is a slot under the covering which is hard to find in the center of the upper aileron that would accept the anchor for the linkage.

It appears to be very easy to install the anchor in the wrong place on the upper aileron which is born out by the fact that someone else has done the same thing as shown in the picture. I have seen several other pictures online that show the same mistaken placement. Pretty easy to fix with a new anchor cut from light ply and epoxied into the correct slot in the aileron.

Fixes the differential issue and washers as shims on the LE of the upper wing at the strut/cabane anchors will change the wing incidence to 1 degree positive very easily without taking anything to pieces. I've seen several posts reference the struts being different by 1/8" and not labelled as front/rear in the kit. No mention of that in the manual either.

Something to be aware of if you plan to assemble this ARF. Flies okay now but pretty sure the changes will make it more fun to fly.

COG is 4 inches from leading edge of upper wing per manual and is right on level at that setting.