The manual says to use 30 minute epoxy and apply to the exposed half of the dihedral tube, the inside of dihedral tube box and then slide the 2 wing halves together keeping them aligned. The wing is 66" long but not all that wide so transport shouldn't be an issue. [8D]

Thanks for the quick reply Fastsky ! This will be my second attempt with the Decathlon. The first one was the Seagull version which had no tube. It really beat me down trying to take off gently.... I had to warn everyone that I was on the runway ! LOL ! It had a mind of it's own ! I wound up selling it at Perry. I would have given the buyer $5 bucks to take it off my hands ! Hope I can do better with this one.....[X(]

Ugo

It took me a few times to figure out the best takeoff method. What worked best for me was to slowly throttle up and watch for plane to start to turn right. When it does, add in rudder to correct and keep the plane tracking straight and from that point, increase the throttle rapidly. About 5 seconds later the plane will leave the ground in a nice slow ascent but building speed until I add in elevator. Then she climbs hard and fast!! I tried the hit the throttle and go method but the plane will suddenly turn on you with no time to correct. [X(]

I think I tried that method too ! Everything but Hand Launch ![X(] LOL ! My next method was to get one of the guys to hold the tail while I power up and let go on my signal !! OR use a Bungee Cord Sling Shot ! Just Kidding, I will try your method again and hope for better results this time. Ishould get delivery next Monday...Along with anew GMS.47 !

Ugo

Looking forward to hearing about your test flight!!

Best takeoff method for mine is what works for eveything.

If you can taxi the airplane you should be able to takeoff safely.

Taxi it out to the runway. If you can do that, the rest is going to be only a tiny bit harder. As you line it up, start to taxi it again. Straight down the runway. Then advance the throttle. Don't firewall it and pray, just advance it.

The airframe will have a chance to start flying as it increases speed. The engine and prop will not have the chance to throw all it's torque and twists at the airframe before the airframe has a chance to fight back. As soon as the airframe starts flying, the engine/prop won't be an issue.

Steer the airplane all the while with the rudder. You do that all the time when taxiing. It's not any harder to do during takeoff. Unless you firewall the throttle before the airframe is flying that is.

The airframe can't guide the airplane before it's up to flying speed. It's got no purchase. It's just along for the ride until it's to flying speed. So give it the chance to get to flying speed. It doesn't take long. But it does take longer than it takes for the prop and engine to have an effect. They're already working quite effectively. They've pulled the airplane all the while it was taxiing, right. Give the airframe a chance to be working too. The rudder on this airplane especially needs a bit more speed to start flying. Until it is, slamming the throttle forward is kissing that airplane goodby.

The rudder on this plane is super effective, even at takeoff speed. I have 50% expo dialed in on mine, and it really helps keep things tamed down on takeoff.

Enjoy!

Hi Guys,
I have a new OS FL70 4 stroker I'd like to put in this plane. Don't think it's too much for plane advertised at 7lbs. Is anyone flying anything similar? Any idea on how the engine/muffler will fit? How about CG?

Thanks,
Ken Cz MI

I don't think anyone's posted in here for a while, but I just got a Phoenix Super Decathlon and am super psyched for it. Started the assembly last night and got the wings and tail done, and got some striping done as well as painted the gear and wing struts. I've got an OS 55AX for power which will be swinging a 13x5 prop to start. Have a larger fuel tank in the mail and when that gets here should be ready for maiden on Wednesday at club night (what the heck is with the tiny tank on this honking 40 size plane?)

garcfield What size fuel tank did you order for the SD???

10oz. The tank it came with is less than 8oz, I think I usually fly with a 8oz and this is a bulky plane with a bigger engine.

Thank's For the info.

Anyone flying a 4 stroke on the SD? If so, what size and prop?
Did anyone compare the Phoenix SD to the Seagull SD with the slightly greater wingspan? Quality of kit, etc?

Yep, I'm using a 12X6 on a Saito 65. I just listed it for sale here:

http://cgi.ebay.com/Super-Decathlon-...3286.m14.l1318

I read some REALLY TERRIBLE reviews of the Seagull plane. The Phoenix plane looks great so far, hoping to maiden it on Wednesday.

Does anyone have suggestions on how to mount the fuel tank in this plane? The directions say to install the throttle linkage first, which is right in the way of the fuel tank.

Hi!

I've been flying the SD Decathlon with an ASP 61 4-stroke. Used 13x6 and 14x6 prop.
I personally found the SD a little underpowered during take-off with the 61. It seemed to loose/lack much speed at the first stage of the climb and often tipstalled.

I have an ASP 80 4-stroke ready to be mounted in the plane now. Really looking forward to see the results.
Loved flying the decathlon, but hated the tipstalling.

Maidened my plane last week and it's been a handful. It's hit the ground 3 times so far without me telling it to! Having trouble getting the OS 55AX to run reliably, and the plane is definitely porpousing and climbing out of dives - might be too tail heavy (balanced perfectly at the 100mm point).

I also noticed the stab has 2 degrees of incidence, and the wing has 0. Is this consistent with anyone else's?

After I finish up some minor repairs I'm going to try to hack off some weight from the tail. I've tried a 13x6, a 12x6, and a 12x8, but again have not been running right so still need to experiment. I wasn't happy with the really high rpms of the 12x6 though.

I ended up with a tank just under 12oz.

Congrats with your maiden. Even though it might have been stressful. The 2 degrees incidence of the stab is most likely because:
The Decathlon is designed to be an aerobatic airplane, therefore it uses a semi-symetrical main wing airfoil. The bottom camber is about half as thick as the upper side of the wings, depending on the airfoils name and variety. Because of this thickness difference it actually has more drag over the wing than under and without your positive incidence to lift the tail a bit, the aircraft would raise its nose continously.

If the aircraft is climbing out of dives, it does not have to be tail heavy because of this tail incidence versus main wing thing. If it balanced perfectly at the given example of CG, then I think your engine needs a little bit more downthrust.
I was using about 3 degrees down, and over 2 right wiht my 61 4-stroke. Might even become more with my 80. It seems that most people don't think to much about this. But it really is important. To o little right thrust makes the plane slip to the left, making takeoffs critical because of more lift on the left wing as an indirect result of this, causing the plane to tipstall to the right!
Too little down-thrust makes people think "****, it's tail heavy". And in an engine out situation, the nose will then be waaay to heavy because of removed weight and this again causes much shorter gliding distance. OK! IT IS MODEL AIRPLANES! But shorter gliding distance=MOST PROBABLY THE 4 OR 5 FEET YOU CAME SHORT OF A SAFE EMERGENCY LANDING! Or you JUST MISSED the top of that tree because the plane came down too fast...

Some things to consider. It's just things I have learned during my modeling career. Hope you can get something out of it.
Anyone who disagrees surely have some other cool ideas of fixing these tendencies.

I was flying the SD with a Saito .82 and APC 13/8 prop. I installed a 16oz tank with tail mounted battery and servos. I had the same problems with terrible takeoff tendencies, while practicing proper takeoff techniques. While at a fun fly I was told to try towing in the wheels to help with the takeoff issues. To my surprise the more I towed it in the better takeoffs became. I had about 7 flights on it prior to adding tow in, and I was ready to sell it! After adding tow in I was begining to have a ball with this plane. The following day of the fun fly I miss judged some tree tops and damaged the fuse and wing beyond repair. I will be ordering another!

Thanks for that tip, I actually sold mine so I could get something that suited me better, but the guy I sold it to is having a really rough time getting it off the ground. I noticed that a couple of hard landings had his gear toed out, not in, so that should really help. I feel bad he is having such a hard time with it.

And after you helped him correct the toe, it was again easy for him to take off and land ????

You did help him, right ?

I've had mine for a bit over a year now. Currently I have a SuperTigre .50 in the nose, and find it a pretty good match. I do wish I went the route of a 4 stroke though. The two strokes really scream, while the 4 strokes sound much more appealing

Anywho, the only thing I have found on mine is that I really need to take the wheelpants off and put bigger tires on it. We fly off of grass here, and unless it's freshly mowed, it has issues getting up to takeoff speed. Other than that I love it... pretty relaxing plane for me. Not a 1st or 2nd plane to say the least, but relatively nice nonetheless.

You better believe I help him!!! And, I'd still buy it back if he didn't like it. Although the first thing he did was drill into the engine and install a smoke system and do some other small mods, so not for full price.

I have to say the plane HATES the extra weight! Keep this thing light!!!

Just got a Phoenix Super Decathlon for my birthday. I'm planning to install a K&B 61. Has anyone else used this engine in their Decathlon? If so, how is the performance, CG, and the fit under the cowl?