I've been flying my 50cc 540T for a long time now. Got one off the first batch and have been flying it since.

From day one I have had trouble with this airframe performing right. It will not harrier, rocks harder than Metallica when you try. Flat spins... nope. Tends to be balky when you try to enter, even trying various entery methods. KE coupling on high alpha is awful to the left but ok to the right, making it very hard to mix out.

All these items together have really dulled my enjoyment of my aircraft. I have done everything I can and am unsure if I want to continue with this airframe or get something new.

All up weight is 16.5 lbs so its light. I have tried the CG everywhere, laterally balanced, sealed the gaps where the wings hit the fuse and everything else I could think of.

A friends edge flys great doing all this and having watched carefully when he flys his, there is no tricks I'm missing. To harrier he just is holding back elevator and crusing arround, the way my cap flys. His spins work great and his KE doesnt couple like mine at all. I asked the builder about it, no tricks at all. Quite frankly I think mine is build as good or better than his, so why wont mine fly worth a damn?

I'm putting it down to freak chance and a bad airframe, but I will open this to discussion before I sell the airframe and get an ultimate to play with.

- Ian

Did you check the wing and H-Stabilizer incidences?

I would also check to see if all the servos are working properly with full torque.

This can be one of the toughest problems to diagnose. If one (or more) servo is weak or slow it can cause all kinds of wierd behaviour.

TF

Tom, could you please tell me how to check servos under torque to see if I may have a bad one? I am currently experiencing a problem after say a snap roll were my engine rpm's drop to a idle until I bring the throttle stick to a idle then power up again. I know futaba has a fail safe if Rx bat drops below 3.8 that would cause this so I installed all new batt. in plane. Seemed fine for 6 flights but it is back.

sounds like you need to replace that throttle servo

Could you tell us what you have for radio, servos etc?

Incadences have not been checked. Servos appear to be ok and torque/speed seem to be ok. I have done some preliminary checking for blowback and I dont seem to have any.

Radio has been a JR 8103 and I just got a 10X, not programmed for that yet. I have tried adjusting my rates too, so I have ruled out too much/little throw.

Servos are Hitec 5645 digitals on everything but rudder which has the big hitec... unsure of number, plenty of torque tho. The ailerons were experiencing some servo chatter so I have some 5945's that I am going to replace them with, have not flown since replacing though. I need to do some minor repairs and then its back out to the field for another round of fighting with the edge.

Aside from weak linkages and incidences being incorrect I am beat. I have 2 buddies that fly the Edge and no such problems exist with theirs I hope you get it figured out.

I think I would start with the incidences. and recheck the lateral balance.failing that I'm stumped.

Maybe a warped wing?

R/C Pat, I am using a 9c radio with a 8 channel pcm Rx. Throttle servo is a 425bb Hitec. Ailerons are 5945mg's. Rudder is a 8611. Elevators are 3421 JR. I have a new 2400 mah radical rc battery. When this plane acts up I have full control of all flight surfaces except throttle which comes back after a few seconds. Engine is a BME 50. I cleaned carb and installed new diaphram and gaskets, installed new fuel lines, cleaned fuel filter, and installed new spark plug. I just dont want to loose the plane because of something stupid.

Incidences would be the first thing I would check. Next, run the trimming sequence by Peter Goldsmith in the Model Aviation Feb and Apr mags. Even if the wings are the same weight you still might have some balancing to do when the wings are under an aerodynamic load. All your mixing troubles could be caused by the combination of these two things (incidence and trimming).

Good luck! Let us know what happens!

uggh... I hate screwing with arfs like this, but I said I would give the edge one good chance more before I replace it, so I will. Time to see if I even have an incadence meter.

If you don't have an incidence meter, I do.

Mike Wickizer

Sorry Blue my question was for vypr However I did have a similar problem to yours with a choke servo. Changed it to a hitec 525 never had a problem since. I would also double check all fuel line connections to make sure thet nice and tight.

See next.

Ice Blue, I experienced this on my H9 Cap 33% with 2 6V NiMH 3300 MaH packs, not fun! I purchased and installed a Electrodynamic EDR-111 optical isolator http://www.electrodynam.com/cgi-loca...6df+1128450034 and cured ALL the problems. Servos are much stronger and faster and no throttle fail safe situations at all, it is rock solid and the optical isolation adds more safety from radio interference.

I've had mine for just a little over a year(2nd batch) and I'm just now getting it dailed in where I like it. The plane has been fun to fly sport with but 3D'in it was a bit puckering to say the least at times, it would start rocking and scare the crap out of of me so I would just stop trying.

I've finally figured it out though. first of all NEVER assume that the plane will build with the correct incidences out of the box, they never do. With the airfoiled tail being as effective as it is there is zero tolerance of mis-alignments, trust me on this. My edge had enough play in the stab mounting holes that I could vary the incidence by + or - 2 degrees on the right side and about a degree on the left. You HAVE to use a meter to get this right or you will be chasing your tail.

Lateral balance is the second issue to be addressed and should be checked by supporting the model, hatch off, dead center by a cord. You can make a fixture that will slip between the motor box sides in the lazer cut holes.

While both of those steps really can help they pale compared to the last step that has been to date the hardest for me to get right but each time I tweak it the plane flies better. GET THE ELEVATOR HALVES TO MATCH PERFECTLY though the whole trave from 50 degrees up to 50 degrees down. I can't say this enough, you CAN NOT eyeball this so don't even try. Get a couple of clothes pins and a length of .070 carbon fiber rod. The CF comes in 24" lengths so you can cut it in half and glue the rods to the clothes pins. Clip these pointers on the elevators and bring the tips of the rods close together behind the rudder. Now turn on the radio and the plane and test the set up, chances are you'll find that they don't match each other, especially at the extreme limits of throw. Getting these two halves synced together can be a real pain in the backside but it WILL kill the rocking everyone keeps experiencing. I've used this technique on 3 other planes that had rocking problems and it has solved the problem on all of them.

I second Shogun's comments regarding the elevator halves..I had terrible rocking even with my incidences at 0..I then tuned the elevator halves at full deflection and all points in between and 98% of the rocking went away..It drops like a profile plane in a elevaotr now..Im still working on harriers but I can take the elevator down to about 50 feet before I chicken out![X(]

Scott, why do you take the hatch off when laterally balancing??

In the grand scheme of things it isn't necessary. consider that the weight of the hatch is more or less symetrical from left to right as the shape doesn't vary from left to right. The weight of the hatch is also more or less on the airplanes centerline as well so it has little influence on the lateral balance.

Remember the kiss principal? Don't make things harder than they have to be, especially when it's hobby related!

Simple...exactly...that's why you can forget all about the fancy string trick and do your lateral balancing dynamically -- while the airframe is under a load.

Have you flight trimmed your plane yet? About the forth step is to laterally balance by taking the plane up about 500 feet, going into an idle dive straight down, and pulling out after about 2 seconds, if a wing is low, that is the heavier wing, add weight to the other side...even with wings that are the same physical weight, there could be other issues that cause your plane to be out of "balance."

Do it Peter Goldsmith's way, JR Team Leader, TOC competitor, he is the man! Just read your Model Aviation - Scale Aerobatics Article in Feb and Apr.

There's also a helpful thread on this here in RCU...just type in "Peter Goldsmith" in the search box, look at the one that is titled "Thanks to Peter Goldsmith."

Doing it with the string is simply a way of getting close to start with. Often it's so close that I rarely have had to add any additional weight to my planes.

I suppose you build the plane and then just throw it in the air to check the CG as well?

Of course the model should be (flight trimmed) after getting all the preliminary set up tasks done.

Shogun, FlyinTiger, Jeremiah, mstroh, and Greg,

Thanks to all of you guys for providing such good examples of how to do things right. It's nice to know you guys are still there and coming through for the new guys.

Pat

I too have issues with my Edge. It is also from the first batch and has about 100 flights on it. I corrected the incidences, adjusted the CG to where it needs a little down to maintain level flight when inverted, and matched my elevator halves. The wing is not warped. Servos are 8611s everywhere. I laterally balanced the plane in flight until it stalls straight and even. Now when I try to hover or torque roll it the plane needs max rudder deflection to keep it upright on it's tail due to all the weight on the left wing tip. Someone mentioned it might need more right thrust than what was built in. This is more work than expected and when the cowl comes off all my equipment is getting pulled from the plane!

Maybe I don't understand, but are you saying it is easier to strip the plane bare than adding a couple of washers to a couple of the standoffs?
Please elaborate, cuz that makes no sense to me at all.

Spar

Sparhawk,
Every time that an issue is corrected something else pops up. I would rather spend my time flying than trimming a plane. If you do not understand search back around a years time to research the ballooning on landing issue the plane had. It was from incorrect incidence from the factory. Easy to fix but a pain in the a*s to figure out. If you still do not get it read my second sentence.

Regards,
Jon