seagull superstar C of G + Tips

[Peachey24]

Just had the first flight with my seagull superstar 120.
A little advise would be good......

I took off in a moderate wind once i got in the air i noticed that when i slowed to just below half throttle it seemed to be very tail heavy. i balanced it from the end of the sheeting from the leading edge of the wing and it seemed ok on the ground, it was a bit nose heavy but i wasnt too bothered as its better to be nose heavy than tail heavy!

Anyone have any ideas as to why this happened, anyone own one of these models, am i measuring the CofG in the wrong place?

Couple of things i noticed with the plane......

If anybody is going to buy one of these models... change the Tail wheel to somthing a lot stronger or change to tail dragger as my tail wheel snapped off due to bumps on takeoff

I suggest changing the undercarriage to a setup which is a lot more "springy" as on the landing it bent one side and as there is no flex on this undercarriage it could have easily ripped off the bottom of the plane! Luck!

So if anyone can give me a tip on the C of G and the best way to balance the plane, anyone made a balancer? it would be appreciated

(Brilliant plane though even though i only did one circuit!)

Cheers

[Zee]

Where the sheeting end's don't realy tell you about CG. I would start at 27% from the L.E. and than adjust as needed.
As far as the landing gear goes, too springy can let you bounce all the way down to runway. If you brake tail wheel and bend the main gear, youmay drop the plane on the ground during landing or drove it in to the ground smooth landing will not do that. The CG may have something to do with that.
Zee

[Peachey24]

The end of the sheeting was refering to the instructions which i believe are incorrect. i spose i didnt run it with the FG cowl on so that may bring it foward a little, cheers for the input

[Zee]

Yes if you leave cowl off that would change the CG. I always check the CG my self, as I have see many drawings with wrong CG informations. 27% is safe location for CG and you can make slight adjustments with Battery location.
Make sure that you have all the parts on the plane when you check the CG.
Your engine will cool better with cowl on.
Zee

[Peachey24]

Cheers Zee, i'll go back out in the freezing cold to recheck the CofG with cowl on. do you rekon tieing string to the wing tube at the center if the fuse may work well?

[Zee]

That depend on where the wing tube is located, and also would the wing balance on the wing tube? I never ballance just the fuselage, as wing can change it when installed.
I get everything put togetter and than check CG.(what you mean freezing? I live in Colorado and just been outside in my T-shirt) :-)
Zee

[Peachey24]

The wing tube is about 2inches back from the suggested c of g, just checked! damn that would have been a good place to balance it aswell!

Had snow sunday, today it was freezing in our workshop. Theres ice on the roads now its really really cold, i wish i was where you are in the world! That would be a dream, i could go out flying whenever i wanted too! i normally go out every sunday, rain or shine! i'm a bit of a cowboy flyer! its good practice flying in these conditions, unfortunatly you gotta know when to quite, plus its not quite so fun flying in moderate wind!

[Doppelganger]

I balance all my planes on the wing tube. It's a perfect place to start, then tweak as needed. This plane is a good flyer. Just don't slow it down too much when landing. It will drop a wing very easily. As for the tail wheel, go with a Sullivan.

Steve

[Peachey24]

cheers steve, i'm gonna play with it a little more tonight, do you just attach string to the tube both sides then hang it in the air, the other idea i had was to drill two small holes either side of the fuse at the suggested c of g (130mm back from the wing leading edge) then put string through the holes and hang it like that coz then i could put the cockpit on and make the plane complete? good idea or bad? heres an example of what i mean! i could then cover the 2/3mm holes with some decals

[Peachey24]

right... ive hung the plane up, c pic. NOSE HEAVY, i've balanced it approx 2 inches behind the stated CogG, battery 1/4 back up the fuse. does this look about right?

[jfstrama]

This is the article that I followed when I helped someone at our club build one. It was right on!

http://www.rcgroups.com/forums/showthread.php?t=544851

Reinforce that landing gear box if you have one that didn't get the factory mod!

MadDog Joe

[Peachey24]

cheers maddog, I just been reading your posts in rcuniverse! about when you first got yours! lol,,, My balance seems really odd cos it is tail heavy but every single artical and review i read people are putting there battery packs in the back! I'm just building a battery tray behind the fuel tank so hopefully that should get the weight to the front!