Have anybody move the CG a little back to make the plane less pitch sensitive?

The solutions for pitch sensitivity are less elevator travel and/or more expo. Moving the CG back could cause serious flyability problems.

Jim

Remember the elevator is in the front, so the forward the CG the less stable the plane would be. The same when the elevator is in the rear the aft the CG the less stable the plane. The close the CG to the elevator the more pitch sensitive the plane is(until certain point of course).

I have not fly a Long-EZ carnard but I used to fly a Firebat carnard, I'm talking by experience. I like to experience moving the CG a little at a time will not cause "serious flyability problems". Also the long take off runs could be attributed to a nose heavy condition.

My Rich model came with a black weight for the front. Did you all have to use it? Also how about receiver and battery placement, any suggestions or success stories?

Thanks

Shayne

That part of your analysis is not correct. Stability and pitch sensitivity are not the same thing. On a Canard moving the CG rearward will decrease pitch sensitivity, but it will also decrease stability. The canard wing must stall before the main wing. If the main wing stalls before the canard the airplane will be unflyable. Moving the CG back raises the loading on the main wing and decreases the loading on the canard, making the main wing more likely to stall first.

The recommended CG on the Rich Model Long EZ is about right if you balance it with the tank full. If you balance it with the tank empty you are already pushing the rear limit of stability. Move it back a little more and then pull a high G turn and you may no longer be in control of the airplane.

Jim

Well I finished it tonight. I am not happy with some of my work but oh well.[>:][>:] I hope I can fly it. All I have left to do is CG it. Thanks for all the info this thread has been very helpful. I have 2 more arfs to build. I don't think I have built an ARF with out messing it up some how but with the way I fly I will have plenty of practice.

Bob, did you ever get yoor Quickie flying yet? I was thinking of getting one to complement my Rutan stable. Let us know how it flys, I am having a ball with the LongEZ.

pete

I wanted to thank everybody for the great input. Hopefully, the maiden goes as well as the build.

jmupilot...I have been reading your reports on your canard. I fly the canard shown at the left. You asked about trim changes at different conditions. On mine I found that adding some nose weight reduced the tendancy to require trim changes at different conditions. Since I designed mine I had to make many CG changes to settle on a location. My canard seems to have a broad range of CG location, but becomes more steady in pitch with a little extra nose weight. Does your model have rudders at the wing tips? Mine does and can knife edge all day long. Even does a knife edge loop. Yours is a very good looking plane. Mine is a SPAD type plane and I describe it in the S.P.A.D. Forum. I look forward to reading more flight reports from you.

Thanks for the info on canards. No the LongEZ I'm flying doesn't have rudders, just vertical fins. The full size LongEZ doesnt have rudders either so to speak, as they only swing out on the same side as the aileron that is in the up postion to compensate for adverse yaw. Meaning a left turn using aileron would have the left aileron up and the left rudder would swing out slightly to compensate, the right rudder would remain inline with the vertical fin. On breaking during the rollout after touchdown both rudders swing out to act as airbrakes. The Richmodels Long EZ is just a semi scale version. Heck watching most modelers fly, I can say that the vast majority of them never use the rudder after thier planes leave the ground its just a bank and yank for most fliers. Just look at some inflight videos of models that have the cam pointed backwards, and see how many times the rudder moves after take off. I know I'm guilty of it, but I've cheated now that my radios have mixing. HEHEHE, I can now fly one stick and get rudder input with ailerons.

I have a few SPADs myself love 'em, cheap way to fly and experiment. I was asking about trim changes because some of the guys in this thread balanced their LongEZ with full tanks and I balanced mine empty. By doing so I have my CG slightly rearward of the full tank balancers. So you guys that balanced with full tanks does your model change trim when at full and low throttle setings?

Pete

JMUPILOT

jmupilot...Thanks for the reply. Still suggest you try a little more nose weight.

You seem to know a little about the full scale LongEZ. I have been following the full scale one for close to 15 years now. The brother of a friend of mine, an airline pilot, was killed in one while doing some low level manuevers. The singer, John Denver was killed in one in California. A doctor in NC was killed in one about 4 years ago in Florida while flying the brand new plane home from the factory in Florida. That one was a little larger version of the LongEZ. I naturally wonder what the problems were. I read the accident reports when ever I can find them.

As you know, canards are supposed to be very safe from stalling and I have found this to be true on my model. My canard can go out of control in a high speed turn if too much elevator is applied. I think it snap rolls and reverses direction. It happens so fast it is difficult to tell what happend. It is a heart stopper. It has happend 2-3 times and I have been very lucky each time. I have since reduced the available elevator travel. I fly all my planes as hard as my nerves will stand.

I have found that the pusher prop cannot cool the engine when on the ground. My engine is 100% open (no cowling). I try to get into the air within 30 seconds of startup. If I need more time to tune the engine I change the prop (same diameter, pitch, and make) to a standard tractor type and play with the engine as long as ot takes. Then I put the pusher back on.

Let me know if you add nose weight and what is the result.

Hey guys, our RichModel Long EZ and Quickie come with a full detailed manual in addition to the factory "diagram" manual which is just not enough to get these planes assembled and flying.
Matt
SeattleMW.com

How do you get one of these manuals. I didn't get one with my arf and would like to buy one. Thanks

Pete,
you seem to have the most experience with the Richmodels LongEZ. I find your comments the most useful, thanks! Do you fly from pavement or grass? I only have a grass field , so I put oversize wheels on it 3.25" diameter. The filed is very long ,so I may use it all.
What do you think about a 61 2c on this ARF? You use a 1/2" throw on the elivator, how muchexpo?
thanks,
Bill

I want one of these but everywhere I check is sold out I'll just keep checking.

Where do you buy these planes at online? The web-site does not have anything. Thanks

I think these guys are a little high priced but here is there web site.

www.SeattleMW.com

If I can find the guy I bought mine off of I will let you know. I lost the address.

you can find the LOng EZ here at RC Universe or at http://www.avia-richmodel.com/
Bill

Yes, Seattle want $190 for the Long EZ, and RichModels was $111.00 + $25 S &H for the exact same thing.
Bill

My Long EZ needed the nose weight plus a little more weight to get the CG right.

Jack

Mine did to. I hope it does not cause an issue.[:-]

I found these on ebay. Should be very nice for air scoops for my cowl. He said he 50 sets.

Item number 6033366990

IMHO these will add too much weight to the already too heavy rear end. (They're stainless)
I'm going to try to make some using large plastic spoons with the bowls cut in half or cutting a plastic pipe at a severe angle. The latter worked well on another plane I had to vent.

Jack

They only weigh 9 grams each that is not even a total ounce of wieght (0.31746569254082607 ounces). I would think the extra cooling is worth 9 grams. Besides thay look really nice.

I fly from grass which is cut close, about 1 inch hi most of the time. Biggest concern I found is that without rudder control be ready for immeadiate correction after lift-off as aileron is the only thing availble to steer with. Practice keeping it straigth as you can on the runway before takeoff. Been on vacaton last week so haven't gotten any flying in. The 61 will work but I'd stay with the lighter 46 class engines. You dont want any more added weight than you need to put in, lighter always flys better. Mine has a OS 46 FX and its more than enough. After tinkering with front strut length some mine is using a normal amount of runway now. I can get it slowed down really well and it lands light as a feather, sometimes it floats past my intended touchdown spot. I'm going to play with the throws next and see what happens. I have looped, rolled, and tried inverted flight and its the same as any other model. Elevator is a litle sluggish but that may be the amount of expo, so I'm taking some out. Nice thing about Computer radios is I can have 2 sets of parameters with the dual rate switch to play with and then keep the one I like.

Sirex, I like the scoops, I made some from the package that a Goldberg spinner came in. Its light and I sprayed the inside with white paint and gluded it on the cowl side, hope it works as I havent got to test it yet. All my flying has been with out the cowl. Has anyone else gotten a flight in yet? Anxious to hear what others are experiencing with trim changes at various throttle settings. And those dang vertical fins out on the wings!!!!!!! Knocked mine off 3 times already, just not used to anything being out there I guess.

Pete