Finally the Decathlon flies. I am slow enough on an ARF that I would never finish a kit. Took the 78in. Super Decathlon out Sunday for its first flight. Already had the CRRC26v2 broken in. A little work on the throttle curve and we were ready. It flew great!! No signs of snapping at the throws I used. I even went to high rates to make it snap. All it did was a really tight loop. I took Mike B.'s recommendation and set the CG at 80mm. I may move it back a little after checkout. Has plenty of power with a 16x8 Hawk prop. The only difficulty is getting it in the air. Because the fuse is short, it has a rather acute angle on the prop. Giving it throttle slowly results in a sharp left turn. Then the correction makes it go right and another left correction has it going down the runway like a cockroach on the run. The best way seems to be more aggressive on the takeoff roll and get the tail up quickly. That stabilizes the yaw and allows finer control. I'm not complaining. If they all flew like trainers, it would be really boring.

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Congratulations. I have the same experience with Decathlons. Good in the air and aerobatic, but a challenge to get there. Nice job.

Yea, you don't want to sneak up on that throttle, nor do you want to zip it up too quickly.

The good news is, you'll get the hang of it very soon, then you won't even give it a second thought

I fly mostly 30-33% gassers. Got rid of most of my glow stuff through attrition and donation. I had a glow .40 size Decathlon years ago and a .40 Clipped wing Cub. The big ones aren't near as challenging. My next project will be a 49in, .60 size Christen Eagle. I got it a a roadside junk store for $5 still in the box. I saw the yellow ARF sized box with "Lion Brand Christen Eagle II" on it when I drove by on the way home from the field and had to turn around and see what it was. The man told me that all the parts weren't there so he would take $5 for it. I asked what was missing, and he said the motor wasn't there. The box said it was for a .60 to 1.20 glow engine so he thought it was supposed to have a motor with it. Of course I relieved of the "incomplete" ARF. I happen to have a GMS .78 looking for a fuselage. It is one of the old printed foam covering types. It is really short. Should be fun.

Hi ec121,

We actually have a separate topic for Seagull 90/120 Decathlons.
http://www.rcuniverse.com/forum/m_82..._9/key_/tm.htm
I'm about to finish mine soon. You made CG = 80mm, that's what I was thinking about (not 100mm as manual says) . Now I have around 88-90mm. What to you think about that? Is it way too tail-heavy or OK?
Initially I'm planning to put 15X8 Xoar on my Saito 125 for that. The prop you used is fine for aerobatics, but the bigger prop creates bigger roll effect during a takeoff. I also equipped mine with Futaba GYA351 gyro which controls the rudder during a takeoff. Not so many guys here who posted flying results for Seagull SD 120 and your recommendations are greatly appreciated.

I had the Phoenix .46-sized Decathlon and really liked it. Had a bear of a time on takeoffs until I cranked some serious toe-in on the gear! I posted about that on the thread for that plane, but I would imagine it would really help any Decathlon, since they are so short-coupled.

My CRRC26 is screaming with the 16x8 on it. I wouldn't want to go any smaller. P-factor is minimal with that prop. And it doesn't use a lot of runway. I think the wing loading is less than the smaller versions. It flies fine at 80mm and the recommended elevator throws. The weather has been bad lately, not much flying. I did take the H9 Corsair out for a quick test flight last Sat. Toe-in is an option. I haven't had enough time to really work out the proper amount of rudder/throttle for takeoff. I should go to the field and do about ten takeoffs in a row to work it out. The tail pops right up on throttle up. Just need to get the air moving over the rudder. A few clicks of up trim would hold the tail down for a bit, but I don't want to be messing with the trim every takeoff. There is a sweet spot somewhere. If I wanted "easy" I would fly my 33% Extra260. It just launches with the ZDZ80 on it. Hardly uses any runway. I like the challenge of doing it right.