I have figured out the landings on this little bugger!! I can nail about 90% of the landings now. Glide in as normal, then about 3 feet off the deck, increase throttle - in my case to about 1/4 to 1/3 throttle. With all the drag, it will continue to sink, but now there is plenty of air over the tail and I can control the direction. I keep the throttle there until it stops rolling. The roll-out is really long, but looks scale-like. The video I posted (post 1033) was just after I figured this out. http://rccd.org/Videos/11%2006%2009%20Camel%202.wmv . Take a look at landing number three.
Hope this helps some of you, although the 1/4 to 1/3 may vary depending on your power system. While the plane is stationary on the grass, advance the throttle until the plane just moves. You need a setting slightly below that for touchdown.

Now THAT is useful, thank you!

I have 3 tail draggers that need throttle to land successfully. With the Camel, I have found that rudder input needs to be at a minimum or it will turn and roll. Wish I had a grass runway as pavement is not forgiving at all.

Harry

Nice!

Snoopy coming along. The tail's done. Gotta start installing servos and wiring in the new lower wing, and rehinging ailerons.

The Camel ailerons are done completely wrong at the "factory" in China. I learned the correct way to hinge with iron on covering from the instructions for building a "Wild Weasel", from RCM plans.

For starters, the angle cut is on top, and it should be on the bottom, but this can be lived with.

Secondly, the builders used one piece of covering on top and one piece on the bottom and covered and hinged at the same time, that's why the ailerons are so reluctant to move very much, particularly "up", which is what we really need on a bird like this, so we can crank in a lot of differential to make it handle nice.

After cutting them off, start by putting the aileron in the down position, and flipped right over 180 degrees so that the flat surfaces are parallel, and use a bit of tape at each end to hold it to the wing. Then, iron in a strip of OD covering between the tape bits.

Next, flip it over and move the aileron to full up, using tape to hold it there.

Iron on the white strip on the roundel first, followed by the gray, then the blue.

Voila. Aileron moves to max deflection in both directions.

What percent differential are folks using that works well?

I don't remember if I even used any when this plane was originally setup, as I did not take the time to get the ailerons rehinged and working right. I'm going to start with 50% this time, and go from there.

I was going to program differential, but ran into the "not enough up aileron" problem Bob mentioned above. Not having differential forces me to get used to using rudder. The Camel is a taildragger even in the air: without coordinating the turns, the tail drags though them!! Constantly flying with rudder makes it feel more natural to use rudder during landing which REALLY helps in keeping the roll-out straight.

I removed the weight box so that I could stand the bird on its nose and check the distance of each wing panel from the table.

The lowers were exactly equal, the upper took a lot of fiddling to get right: drilling out the holes in all the brass "feet" on the cabane struts, and pushing the right side struts aft and the left side forward. Once I got it about right, I poured a mix of epoxy/milled glass over all the cabane mount points so they will stay in place. The upper panels are within 1/16 - 1/8" of each other, leading edge wise, depending on how I hold my mouth when installing the top wing.

The interplane struts are two lengths, and I remember quite a bit of debate about whether the long or short should go on the LE or the TE. The book contributed to this by saying (misprint) that the shorts should go in both places. After I spent all that time getting the upper wing at 90 degrees to the fuse, the long and short of it [:'(] became obvious: the short ones go in front, and the long ones in back. They fit nicely, and the panel incidences are perfect: the lowers are basically 0 deg each; and the uppers are both about 1 degree negative. (Decalage or something they call that, I think. So many lovely French words in aviation.) When I set this bird up the first time, about 6 years ago, I had it all screwed up.

Ailerons are hooked up, so Snoopy awaits the motor and packs for final assembly.

Bob,

The theory on a forward staggered biplane is that the top wing should be slightly positive relative to the lower wing. The idea - at least in theory!!! - is that as angle of attack increases, the top wing will stall first and loose lift. The lower (aft) wing continues to generate lift which is behind the CG and therefore lift the tail/drop the nose, the plane accelerates and continues to fly - - - - in theory. Then there is also theory on how the air is deflected by the top wing, so that by the time it gets to the lower wing the flow is slightly different for the lower wing.

I know I also fussed around with the struts - cabane and interplane - until I found what worked. But the result gave the top wing slightly more incidence than the lower one.

But as with most things in model aviation: Use what works for you. And if it works, don't mess with it!

tree2tree

Actually, the difference between the top and bottom is so slight, less than 1/2 deg, that I'm sure it falls within my measuring tolerance. I'm just putting the meter part of a digital pitch gauge against the bottoms of the wing panels, and it's really hard to get it to even sit still, as I'm pressing it up.

When I built my DR-1, the plans said to set the top wing about a degree more than the other two. I ignored that. I suppose it might be good on a full size, but on a model, I don't want any pitch changes that I don't initiate. There's enough goofy stuff happening with these things as it is without adding to it. Besides, like someone else said earlier, the key to landing these crates is to keep the power on a little and fly them right down onto the wheels. Getting the nose high at all means the wings will blanket the tail and that means big trouble.

Does everybody do this when they're bored and waiting for the motor to arrive?

Ha haaaaaa! Like it!

Bored no longer!

The G-60 mounted real easy and ended up the perfect distance from the firewall on 60mm HK standoffs. Got about a half inch between the back of the APC prop and the cowl. The wood prop will have to use the 10mm collet adaptor that came with the motor, and will be maybe a 1/4" further forward.

After getting the motor in I put it all back together, taped the packs and the ESC (on the table under the nose) to the firewall and did a preliminary balance check at 3.5" back from the upper leading edge. (That represents 25% of MAC, which I prefer over the 4" in the book.) It was not terribly out of balance, but the tail did hang low, so I need to locate the packs as close to the back of the dummy engine as I can. (This is all without the lead block box. )

I'll be making a "false" firewall that will start out by attaching to the cowl blocks, then will have further attach points added between it and the real firewall. I plan to construct some vertical boxes on each side of the motor, built onto the false firewall, so that the packs can be slid up into them from the bottom. (I'll be cutting away just about all of the bottom of the cowl between the mounting blocks and aft of the dummy engine.) After all that's done and the packs are securely mounted, I'll recheck the CG before installing and wiring the ESC. Whew.

Finally the upload is working again. Wouldn't have been much point in talking about this mod without pictures.

Going to the trouble of getting the two 3000 6S packs right up behind the dummy engine really paid off. The balance is where it should be, and I can mount the ESC behind the firewall, which really simplifies the wiring. It also gets the ESC directly behind the hole in the firewall for cooling. I cut out the covering in front of the tail skid for a cooling air exit that's not too conspicuous.

I had to get the dummy rotary further forward than stock, so I cut off all the pushrod tubes and the outer plastic that extended beyond the cylinder heads.

The battery boxes themselves were pretty straightforward.

A basswood crosspiece between the battery boxes has a blind nut on the other side, and a bolt through another piece of basswood retains the packs.

Snoop's ready for wiring. Should be RTF tomorrow, after programming the ICE esc and some current/rpm testing.

RTF

Looks like I won't ever need full throttle on this. The Castle Link indicates about 60% throttle will be more than enough, about 42mph and almost 8# of thrust. If I want it for vertical stuff, there's about 20# on tap. Whoosh!!

She was hanging slightly tail down at the 3.5" point, so I did go ahead and use my Harry Higley Heavy spinner.

Did two test flights this AM.

First time, nosed it over once trying to take off, then nosed it over on landing cause I couldn't slow it down. Ran out of up elevator trim during flight, indicating that the lifting tail is doing what it's sposed to.

Second time, removed the brass prop hub and subsituted the aluminium one. Changed the servo arm locations to get more up elevator. Lovely, easy takeoff and sweet, somewhat tail down landing. Cruises at about 35mph on 15 amps. Takeoff amps was 33, and max was 38 during a go around. ESC temp stayed below 100F. She has a bit of up elevator trim, now, which was never the case before. (It was always down trim quite a bit to make it fly level.) The best part is that there is no pitch/speed/thrust coupling: when I nailed the throttle on the go around, she just pulled on out level.

Bob,
Glad things are going well. Congrats!

Hey, TC, how ya been?

The wind finally quit howling, here, so I got to fly Snoopy again today.

The combination of a lifting stab and the recommended 4" CG works great. The stab keeps the tail up where it belongs, from low to high throttle, and the aft CG cures all the ground handling problems. No nose overs. No wandering about on rollout.

On takeoff, I'm finding it best to throttle up to 1/3 right away, so the tail comes up quickly and yaw and pitch control is established right away. Gonna try that with my Triplane.

It is a WWI rudder turner, too. Rudder into the turn, apply back stick, then opposite aileron to keep it from overbanking. Roll out with aileron.

Haven't tried to roll it, yet, but it sure does pretty great big loops from level flight, and after a 5 minute session today the packs only took about 1500 mAh. (6000 6S)

This one's a keeper.

RIP Minnflyer. You put me onto this bird.

Bob,

I just started building my Sopwith and I'm looking to do an EP setup because that's what I'm most familiar with. I think yours is a good setup that I'd like to try. I was wondering, are these the "60mm HK standoffs" you used?
www.hobbyking.com/hobbyking/store/uh_viewItem.asp

Is the plane still flying OK? Thanks for sharing!

Mike

Mike:

These are the 60mm standoffs I used: http://www.hobbyking.com/hobbyking/s...dProduct=21289

The bird is flying great. The lifting tail, combined with setting the CG at the recommended point, removed all the bad habits this airplane used to have.

Bob, glad to hear Snoopy is flying well. How did you make your tail lifting? Did you just change the angle of attach?

tclaridge:

I downloaded a Clark Y profile, and then ended up making it about half the normal height for the chord of my tail. It might have a bit of positive incidence, relative to the lower wing, but that's all.

Before I did this, there were two modes of operation:

1. With the CG at the H9 recommended point of 4" back from the top wing LE, it was unstable. If I let it slow down to normal approach speed, then tried to turn, the tail would drop and it would try to spiral off. It was very stable on the ground, tho, with no tendency to nose over, and slowed down really well for landing.

2. With the CG at 25% (about 3.5") it was stable, but it wouldn't slow down for landing and on the ground during takeoff and touchdown it did not track well at all. Constantly veering off and digging in a wing tip. (Twatting, I think someone called it. Happened a lot.) Using rudder was no help. It was so bad that when I did the E conversion, I had to buy a new lower wing set because the original was banged up to the point of not being repairable.

The lifting tail canceled out the instability at the 4" CG point, is very strong (a 1/16 sheet balsa bottom and 4 1/4" square spars) and eliminates the need for the flying wires. The best part is being able to turn into the wind and nail the throttle and not have it balloon up, which is so characteristic of WWI models.

Bear in mind that none of this alters the truth that if you don't take off and land into the wind with this bird, you'll get into trouble in hearbeat. Anyone who says they can do that in crosswinds is pulling your chain.